[Vendor] blevesearch v0.8.1 -> v1.0.7 (#11360)

* Update blevesearch v0.8.1 -> v1.0.7

* make vendor

Co-authored-by: zeripath <art27@cantab.net>

136 files changed, 8640 insertions, 6531 deletions

diff --git a/vendor/github.com/RoaringBitmap/roaring/.travis.yml b/vendor/github.com/RoaringBitmap/roaring/.travis.yml
index 8839c14fd0..c17804322b 100644
--- a/vendor/github.com/RoaringBitmap/roaring/.travis.yml
+++ b/vendor/github.com/RoaringBitmap/roaring/.travis.yml
@@ -14,6 +14,7 @@ go:
 - "1.10.x"
 - "1.11.x"
 - "1.12.x"
+- "1.13.x"
 - tip
 
 # whitelist
diff --git a/vendor/github.com/RoaringBitmap/roaring/README.md b/vendor/github.com/RoaringBitmap/roaring/README.md
index b711d09ec2..94fdf057e5 100644
--- a/vendor/github.com/RoaringBitmap/roaring/README.md
+++ b/vendor/github.com/RoaringBitmap/roaring/README.md
@@ -29,11 +29,17 @@ Roaring bitmaps are found to work well in many important applications:
 
 
 The ``roaring`` Go library is used by
-* [Cloud Torrent](https://github.com/jpillora/cloud-torrent): a self-hosted remote torrent client
-* [runv](https://github.com/hyperhq/runv): an Hypervisor-based runtime for the Open Containers Initiative
+* [Cloud Torrent](https://github.com/jpillora/cloud-torrent)
+* [runv](https://github.com/hyperhq/runv)
 * [InfluxDB](https://www.influxdata.com)
 * [Pilosa](https://www.pilosa.com/)
 * [Bleve](http://www.blevesearch.com)
+* [lindb](https://github.com/lindb/lindb)
+* [Elasticell](https://github.com/deepfabric/elasticell)
+* [SourceGraph](https://github.com/sourcegraph/sourcegraph)
+* [M3](https://github.com/m3db/m3)
+* [trident](https://github.com/NetApp/trident)
+
 
 This library is used in production in several systems, it is part of the [Awesome Go collection](https://awesome-go.com).
 
diff --git a/vendor/github.com/RoaringBitmap/roaring/arraycontainer.go b/vendor/github.com/RoaringBitmap/roaring/arraycontainer.go
index 621616f5df..eb124f3b76 100644
--- a/vendor/github.com/RoaringBitmap/roaring/arraycontainer.go
+++ b/vendor/github.com/RoaringBitmap/roaring/arraycontainer.go
@@ -24,6 +24,18 @@ func (ac *arrayContainer) fillLeastSignificant16bits(x []uint32, i int, mask uin
 	}
 }
 
+func (ac *arrayContainer) iterate(cb func(x uint16) bool) bool {
+	iterator := shortIterator{ac.content, 0}
+
+	for iterator.hasNext() {
+		if !cb(iterator.next()) {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (ac *arrayContainer) getShortIterator() shortPeekable {
 	return &shortIterator{ac.content, 0}
 }
diff --git a/vendor/github.com/RoaringBitmap/roaring/bitmapcontainer.go b/vendor/github.com/RoaringBitmap/roaring/bitmapcontainer.go
index e749721bb2..cd259fd2d9 100644
--- a/vendor/github.com/RoaringBitmap/roaring/bitmapcontainer.go
+++ b/vendor/github.com/RoaringBitmap/roaring/bitmapcontainer.go
@@ -96,6 +96,18 @@ func (bc *bitmapContainer) maximum() uint16 {
 	return uint16(0)
 }
 
+func (bc *bitmapContainer) iterate(cb func(x uint16) bool) bool {
+	iterator := bitmapContainerShortIterator{bc, bc.NextSetBit(0)}
+
+	for iterator.hasNext() {
+		if !cb(iterator.next()) {
+			return false
+		}
+	}
+
+	return true
+}
+
 type bitmapContainerShortIterator struct {
 	ptr *bitmapContainer
 	i   int
diff --git a/vendor/github.com/RoaringBitmap/roaring/roaring.go b/vendor/github.com/RoaringBitmap/roaring/roaring.go
index df58cc30b5..ed75d58b97 100644
--- a/vendor/github.com/RoaringBitmap/roaring/roaring.go
+++ b/vendor/github.com/RoaringBitmap/roaring/roaring.go
@@ -416,6 +416,38 @@ func (rb *Bitmap) String() string {
 	return buffer.String()
 }
 
+// Iterate iterates over the bitmap, calling the given callback with each value in the bitmap.  If the callback returns
+// false, the iteration is halted.
+// The iteration results are undefined if the bitmap is modified (e.g., with Add or Remove).
+// There is no guarantee as to what order the values will be iterated
+func (rb *Bitmap) Iterate(cb func(x uint32) bool) {
+	for i := 0; i < rb.highlowcontainer.size(); i++ {
+		hs := uint32(rb.highlowcontainer.getKeyAtIndex(i)) << 16
+		c := rb.highlowcontainer.getContainerAtIndex(i)
+
+		var shouldContinue bool
+		// This is hacky but it avoids allocations from invoking an interface method with a closure
+		switch t := c.(type) {
+		case *arrayContainer:
+			shouldContinue = t.iterate(func(x uint16) bool {
+				return cb(uint32(x) | hs)
+			})
+		case *runContainer16:
+			shouldContinue = t.iterate(func(x uint16) bool {
+				return cb(uint32(x) | hs)
+			})
+		case *bitmapContainer:
+			shouldContinue = t.iterate(func(x uint16) bool {
+				return cb(uint32(x) | hs)
+			})
+		}
+
+		if !shouldContinue {
+			break
+		}
+	}
+}
+
 // Iterator creates a new IntPeekable to iterate over the integers contained in the bitmap, in sorted order;
 // the iterator becomes invalid if the bitmap is modified (e.g., with Add or Remove).
 func (rb *Bitmap) Iterator() IntPeekable {
@@ -475,41 +507,72 @@ func (rb *Bitmap) Equals(o interface{}) bool {
 
 // AddOffset adds the value 'offset' to each and every value in a bitmap, generating a new bitmap in the process
 func AddOffset(x *Bitmap, offset uint32) (answer *Bitmap) {
-	containerOffset := highbits(offset)
-	inOffset := lowbits(offset)
+	return AddOffset64(x, int64(offset))
+}
+
+// AddOffset64 adds the value 'offset' to each and every value in a bitmap, generating a new bitmap in the process
+// If offset + element is outside of the range [0,2^32), that the element will be dropped
+func AddOffset64(x *Bitmap, offset int64) (answer *Bitmap) {
+	// we need "offset" to be a long because we want to support values
+	// between -0xFFFFFFFF up to +-0xFFFFFFFF
+	var containerOffset64 int64
+
+	if offset < 0 {
+		containerOffset64 = (offset - (1 << 16) + 1) / (1 << 16)
+	} else {
+		containerOffset64 = offset >> 16
+	}
+
+	if containerOffset64 >= (1<<16) || containerOffset64 <= -(1<<16) {
+		return New()
+	}
+
+	containerOffset := int32(containerOffset64)
+	inOffset := (uint16)(offset - containerOffset64*(1<<16))
+
 	if inOffset == 0 {
 		answer = x.Clone()
 		for pos := 0; pos < answer.highlowcontainer.size(); pos++ {
-			key := answer.highlowcontainer.getKeyAtIndex(pos)
+			key := int32(answer.highlowcontainer.getKeyAtIndex(pos))
 			key += containerOffset
-			answer.highlowcontainer.keys[pos] = key
+
+			if key >= 0 && key <= MaxUint16 {
+				answer.highlowcontainer.keys[pos] = uint16(key)
+			}
 		}
 	} else {
 		answer = New()
+
 		for pos := 0; pos < x.highlowcontainer.size(); pos++ {
-			key := x.highlowcontainer.getKeyAtIndex(pos)
+			key := int32(x.highlowcontainer.getKeyAtIndex(pos))
 			key += containerOffset
+
 			c := x.highlowcontainer.getContainerAtIndex(pos)
 			offsetted := c.addOffset(inOffset)
-			if offsetted[0].getCardinality() > 0 {
+
+			if offsetted[0].getCardinality() > 0 && (key >= 0 && key <= MaxUint16) {
 				curSize := answer.highlowcontainer.size()
-				lastkey := uint16(0)
+				lastkey := int32(0)
+
 				if curSize > 0 {
-					lastkey = answer.highlowcontainer.getKeyAtIndex(curSize - 1)
+					lastkey = int32(answer.highlowcontainer.getKeyAtIndex(curSize - 1))
 				}
+
 				if curSize > 0 && lastkey == key {
 					prev := answer.highlowcontainer.getContainerAtIndex(curSize - 1)
 					orrseult := prev.ior(offsetted[0])
 					answer.highlowcontainer.setContainerAtIndex(curSize-1, orrseult)
 				} else {
-					answer.highlowcontainer.appendContainer(key, offsetted[0], false)
+					answer.highlowcontainer.appendContainer(uint16(key), offsetted[0], false)
 				}
 			}
-			if offsetted[1].getCardinality() > 0 {
-				answer.highlowcontainer.appendContainer(key+1, offsetted[1], false)
+
+			if offsetted[1].getCardinality() > 0 && ((key+1) >= 0 && (key+1) <= MaxUint16) {
+				answer.highlowcontainer.appendContainer(uint16(key+1), offsetted[1], false)
 			}
 		}
 	}
+
 	return answer
 }
 
diff --git a/vendor/github.com/RoaringBitmap/roaring/roaringarray.go b/vendor/github.com/RoaringBitmap/roaring/roaringarray.go
index d9d5edda73..3dddbffdbc 100644
--- a/vendor/github.com/RoaringBitmap/roaring/roaringarray.go
+++ b/vendor/github.com/RoaringBitmap/roaring/roaringarray.go
@@ -4,9 +4,10 @@ import (
 	"bytes"
 	"encoding/binary"
 	"fmt"
+	"io"
+
 	snappy "github.com/glycerine/go-unsnap-stream"
 	"github.com/tinylib/msgp/msgp"
-	"io"
 )
 
 //go:generate msgp -unexported
@@ -38,6 +39,7 @@ type container interface {
 	inot(firstOfRange, endx int) container // i stands for inplace, range is [firstOfRange,endx)
 	xor(r container) container
 	getShortIterator() shortPeekable
+	iterate(cb func(x uint16) bool) bool
 	getReverseIterator() shortIterable
 	getManyIterator() manyIterable
 	contains(i uint16) bool
@@ -488,20 +490,15 @@ func (ra *roaringArray) writeTo(w io.Writer) (n int64, err error) {
 		nw += 2
 		binary.LittleEndian.PutUint16(buf[2:], uint16(len(ra.keys)-1))
 		nw += 2
-
-		// compute isRun bitmap
-		var ir []byte
-
-		isRun := newBitmapContainer()
+		// compute isRun bitmap without temporary allocation
+		var runbitmapslice = buf[nw:nw+isRunSizeInBytes]
 		for i, c := range ra.containers {
 			switch c.(type) {
 			case *runContainer16:
-				isRun.iadd(uint16(i))
+				runbitmapslice[i / 8] |= 1<<(uint(i)%8)
 			}
 		}
-		// convert to little endian
-		ir = isRun.asLittleEndianByteSlice()[:isRunSizeInBytes]
-		nw += copy(buf[nw:], ir)
+		nw += isRunSizeInBytes
 	} else {
 		binary.LittleEndian.PutUint32(buf[0:], uint32(serialCookieNoRunContainer))
 		nw += 4
diff --git a/vendor/github.com/RoaringBitmap/roaring/runcontainer.go b/vendor/github.com/RoaringBitmap/roaring/runcontainer.go
index cbffdaf24d..5a0f985f1d 100644
--- a/vendor/github.com/RoaringBitmap/roaring/runcontainer.go
+++ b/vendor/github.com/RoaringBitmap/roaring/runcontainer.go
@@ -1162,6 +1162,18 @@ func (rc *runContainer16) newRunIterator16() *runIterator16 {
 	return &runIterator16{rc: rc, curIndex: 0, curPosInIndex: 0}
 }
 
+func (rc *runContainer16) iterate(cb func(x uint16) bool) bool {
+	iterator := runIterator16{rc, 0, 0}
+
+	for iterator.hasNext() {
+		if !cb(iterator.next()) {
+			return false
+		}
+	}
+
+	return true
+}
+
 // hasNext returns false if calling next will panic. It
 // returns true when there is at least one more value
 // available in the iteration sequence.
diff --git a/vendor/github.com/RoaringBitmap/roaring/setutil.go b/vendor/github.com/RoaringBitmap/roaring/setutil.go
index 3e8c01dd1f..2fe8151411 100644
--- a/vendor/github.com/RoaringBitmap/roaring/setutil.go
+++ b/vendor/github.com/RoaringBitmap/roaring/setutil.go
@@ -14,6 +14,7 @@ func equal(a, b []uint16) bool {
 
 func difference(set1 []uint16, set2 []uint16, buffer []uint16) int {
 	if 0 == len(set2) {
+		buffer = buffer[:len(set1)]
 		for k := 0; k < len(set1); k++ {
 			buffer[k] = set1[k]
 		}
diff --git a/vendor/github.com/RoaringBitmap/roaring/util.go b/vendor/github.com/RoaringBitmap/roaring/util.go
index 3a9a47236b..6763033916 100644
--- a/vendor/github.com/RoaringBitmap/roaring/util.go
+++ b/vendor/github.com/RoaringBitmap/roaring/util.go
@@ -112,7 +112,7 @@ func highbits(x uint32) uint16 {
 	return uint16(x >> 16)
 }
 func lowbits(x uint32) uint16 {
-	return uint16(x & 0xFFFF)
+	return uint16(x & maxLowBit)
 }
 
 const maxLowBit = 0xFFFF
diff --git a/vendor/github.com/blevesearch/bleve/.travis.yml b/vendor/github.com/blevesearch/bleve/.travis.yml
index e00e7b9948..7b7297afe3 100644
--- a/vendor/github.com/blevesearch/bleve/.travis.yml
+++ b/vendor/github.com/blevesearch/bleve/.travis.yml
@@ -3,9 +3,9 @@ sudo: false
 language: go
 
 go:
- - "1.10.x"
- - "1.11.x"
  - "1.12.x"
+ - "1.13.x"
+ - "1.14.x"
 
 script:
   - go get golang.org/x/tools/cmd/cover
@@ -16,11 +16,7 @@ script:
   - go test -race -v $(go list ./... | grep -v vendor/)
   - go vet $(go list ./... | grep -v vendor/)
   - go test ./test -v -indexType scorch
-  - if [[ ${TRAVIS_GO_VERSION} =~ ^1\.10 ]]; then
-        echo "errcheck skipped for go version" $TRAVIS_GO_VERSION;
-    else
-        errcheck -ignorepkg fmt $(go list ./... | grep -v vendor/);
-    fi
+  - errcheck -ignorepkg fmt $(go list ./... | grep -v vendor/);
   - docs/project-code-coverage.sh
   - docs/build_children.sh
 
diff --git a/vendor/github.com/blevesearch/bleve/analysis/lang/en/stemmer_en_snowball.go b/vendor/github.com/blevesearch/bleve/analysis/lang/en/stemmer_en_snowball.go
new file mode 100644
index 0000000000..225bb0664d
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/analysis/lang/en/stemmer_en_snowball.go
@@ -0,0 +1,49 @@
+//  Copyright (c) 2020 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package en
+
+import (
+	"github.com/blevesearch/bleve/analysis"
+	"github.com/blevesearch/bleve/registry"
+
+	"github.com/blevesearch/snowballstem"
+	"github.com/blevesearch/snowballstem/english"
+)
+
+const SnowballStemmerName = "stemmer_en_snowball"
+
+type EnglishStemmerFilter struct {
+}
+
+func NewEnglishStemmerFilter() *EnglishStemmerFilter {
+	return &EnglishStemmerFilter{}
+}
+
+func (s *EnglishStemmerFilter) Filter(input analysis.TokenStream) analysis.TokenStream {
+	for _, token := range input {
+		env := snowballstem.NewEnv(string(token.Term))
+		english.Stem(env)
+		token.Term = []byte(env.Current())
+	}
+	return input
+}
+
+func EnglishStemmerFilterConstructor(config map[string]interface{}, cache *registry.Cache) (analysis.TokenFilter, error) {
+	return NewEnglishStemmerFilter(), nil
+}
+
+func init() {
+	registry.RegisterTokenFilter(SnowballStemmerName, EnglishStemmerFilterConstructor)
+}
diff --git a/vendor/github.com/blevesearch/bleve/geo/geo.go b/vendor/github.com/blevesearch/bleve/geo/geo.go
index 583451e308..b18ace4337 100644
--- a/vendor/github.com/blevesearch/bleve/geo/geo.go
+++ b/vendor/github.com/blevesearch/bleve/geo/geo.go
@@ -33,14 +33,16 @@ var minLonRad = minLon * degreesToRadian
 var minLatRad = minLat * degreesToRadian
 var maxLonRad = maxLon * degreesToRadian
 var maxLatRad = maxLat * degreesToRadian
-var geoTolerance = 1E-6
+var geoTolerance = 1e-6
 var lonScale = float64((uint64(0x1)<<GeoBits)-1) / 360.0
 var latScale = float64((uint64(0x1)<<GeoBits)-1) / 180.0
 
+var geoHashMaxLength = 12
+
 // Point represents a geo point.
 type Point struct {
-	Lon float64
-	Lat float64
+	Lon float64 `json:"lon"`
+	Lat float64 `json:"lat"`
 }
 
 // MortonHash computes the morton hash value for the provided geo point
diff --git a/vendor/github.com/blevesearch/bleve/geo/parse.go b/vendor/github.com/blevesearch/bleve/geo/parse.go
index 5d833d9110..8286805ff7 100644
--- a/vendor/github.com/blevesearch/bleve/geo/parse.go
+++ b/vendor/github.com/blevesearch/bleve/geo/parse.go
@@ -85,9 +85,11 @@ func ExtractGeoPoint(thing interface{}) (lon, lat float64, success bool) {
 			}
 		} else {
 			// geohash
-			lat, lon = DecodeGeoHash(geoStr)
-			foundLat = true
-			foundLon = true
+			if len(geoStr) <= geoHashMaxLength {
+				lat, lon = DecodeGeoHash(geoStr)
+				foundLat = true
+				foundLon = true
+			}
 		}
 	}
 
diff --git a/vendor/github.com/blevesearch/bleve/go.mod b/vendor/github.com/blevesearch/bleve/go.mod
new file mode 100644
index 0000000000..d38cf8f921
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/go.mod
@@ -0,0 +1,25 @@
+module github.com/blevesearch/bleve
+
+go 1.13
+
+require (
+	github.com/RoaringBitmap/roaring v0.4.21
+	github.com/blevesearch/blevex v0.0.0-20190916190636-152f0fe5c040
+	github.com/blevesearch/go-porterstemmer v1.0.3
+	github.com/blevesearch/segment v0.9.0
+	github.com/blevesearch/snowballstem v0.9.0
+	github.com/blevesearch/zap/v11 v11.0.7
+	github.com/blevesearch/zap/v12 v12.0.7
+	github.com/couchbase/ghistogram v0.1.0 // indirect
+	github.com/couchbase/moss v0.1.0
+	github.com/couchbase/vellum v1.0.1
+	github.com/golang/protobuf v1.3.2
+	github.com/kljensen/snowball v0.6.0
+	github.com/rcrowley/go-metrics v0.0.0-20190826022208-cac0b30c2563
+	github.com/spf13/cobra v0.0.5
+	github.com/steveyen/gtreap v0.1.0
+	github.com/syndtr/goleveldb v1.0.0
+	github.com/willf/bitset v1.1.10
+	go.etcd.io/bbolt v1.3.4
+	golang.org/x/text v0.3.0
+)
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/introducer.go b/vendor/github.com/blevesearch/bleve/index/scorch/introducer.go
index ac627796f5..e5f00f80e1 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/introducer.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/introducer.go
@@ -21,7 +21,6 @@ import (
 	"github.com/RoaringBitmap/roaring"
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	"github.com/blevesearch/bleve/index/scorch/segment/zap"
 )
 
 type segmentIntroduction struct {
@@ -77,11 +76,6 @@ OUTER:
 		case persist := <-s.persists:
 			s.introducePersist(persist)
 
-		case revertTo := <-s.revertToSnapshots:
-			err := s.revertToSnapshot(revertTo)
-			if err != nil {
-				continue OUTER
-			}
 		}
 
 		var epochCurr uint64
@@ -312,6 +306,8 @@ func (s *Scorch) introducePersist(persist *persistIntroduction) {
 	close(persist.applied)
 }
 
+// The introducer should definitely handle the segmentMerge.notify
+// channel before exiting the introduceMerge.
 func (s *Scorch) introduceMerge(nextMerge *segmentMerge) {
 	atomic.AddUint64(&s.stats.TotIntroduceMergeBeg, 1)
 	defer atomic.AddUint64(&s.stats.TotIntroduceMergeEnd, 1)
@@ -409,11 +405,11 @@ func (s *Scorch) introduceMerge(nextMerge *segmentMerge) {
 		atomic.AddUint64(&s.stats.TotIntroducedSegmentsMerge, 1)
 
 		switch nextMerge.new.(type) {
-		case *zap.SegmentBase:
+		case segment.PersistedSegment:
+			fileSegments++
+		default:
 			docsToPersistCount += nextMerge.new.Count() - newSegmentDeleted.GetCardinality()
 			memSegments++
-		case *zap.Segment:
-			fileSegments++
 		}
 	}
 
@@ -443,86 +439,11 @@ func (s *Scorch) introduceMerge(nextMerge *segmentMerge) {
 	close(nextMerge.notify)
 }
 
-func (s *Scorch) revertToSnapshot(revertTo *snapshotReversion) error {
-	atomic.AddUint64(&s.stats.TotIntroduceRevertBeg, 1)
-	defer atomic.AddUint64(&s.stats.TotIntroduceRevertEnd, 1)
-
-	if revertTo.snapshot == nil {
-		err := fmt.Errorf("Cannot revert to a nil snapshot")
-		revertTo.applied <- err
-		return err
-	}
-
-	// acquire lock
-	s.rootLock.Lock()
-
-	// prepare a new index snapshot, based on next snapshot
-	newSnapshot := &IndexSnapshot{
-		parent:   s,
-		segment:  make([]*SegmentSnapshot, len(revertTo.snapshot.segment)),
-		offsets:  revertTo.snapshot.offsets,
-		internal: revertTo.snapshot.internal,
-		epoch:    s.nextSnapshotEpoch,
-		refs:     1,
-		creator:  "revertToSnapshot",
-	}
-	s.nextSnapshotEpoch++
-
-	var docsToPersistCount, memSegments, fileSegments uint64
-	// iterate through segments
-	for i, segmentSnapshot := range revertTo.snapshot.segment {
-		newSnapshot.segment[i] = &SegmentSnapshot{
-			id:         segmentSnapshot.id,
-			segment:    segmentSnapshot.segment,
-			deleted:    segmentSnapshot.deleted,
-			cachedDocs: segmentSnapshot.cachedDocs,
-			creator:    segmentSnapshot.creator,
-		}
-		newSnapshot.segment[i].segment.AddRef()
-
-		// remove segment from ineligibleForRemoval map
-		filename := zapFileName(segmentSnapshot.id)
-		delete(s.ineligibleForRemoval, filename)
-
-		if isMemorySegment(segmentSnapshot) {
-			docsToPersistCount += segmentSnapshot.Count()
-			memSegments++
-		} else {
-			fileSegments++
-		}
-	}
-
-	atomic.StoreUint64(&s.stats.TotItemsToPersist, docsToPersistCount)
-	atomic.StoreUint64(&s.stats.TotMemorySegmentsAtRoot, memSegments)
-	atomic.StoreUint64(&s.stats.TotFileSegmentsAtRoot, fileSegments)
-
-	if revertTo.persisted != nil {
-		s.rootPersisted = append(s.rootPersisted, revertTo.persisted)
-	}
-
-	newSnapshot.updateSize()
-	// swap in new snapshot
-	rootPrev := s.root
-	s.root = newSnapshot
-
-	atomic.StoreUint64(&s.stats.CurRootEpoch, s.root.epoch)
-	// release lock
-	s.rootLock.Unlock()
-
-	if rootPrev != nil {
-		_ = rootPrev.DecRef()
-	}
-
-	close(revertTo.applied)
-
-	return nil
-}
-
 func isMemorySegment(s *SegmentSnapshot) bool {
 	switch s.segment.(type) {
-	case *zap.SegmentBase:
-		return true
-	default:
+	case segment.PersistedSegment:
 		return false
+	default:
+		return true
 	}
 }
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/merge.go b/vendor/github.com/blevesearch/bleve/index/scorch/merge.go
index d7144772fd..37dca529a6 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/merge.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/merge.go
@@ -25,7 +25,6 @@ import (
 	"github.com/RoaringBitmap/roaring"
 	"github.com/blevesearch/bleve/index/scorch/mergeplan"
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	"github.com/blevesearch/bleve/index/scorch/segment/zap"
 )
 
 func (s *Scorch) mergerLoop() {
@@ -131,18 +130,18 @@ func (s *Scorch) parseMergePlannerOptions() (*mergeplan.MergePlanOptions,
 
 func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 	options *mergeplan.MergePlanOptions) error {
-	// build list of zap segments in this snapshot
-	var onlyZapSnapshots []mergeplan.Segment
+	// build list of persisted segments in this snapshot
+	var onlyPersistedSnapshots []mergeplan.Segment
 	for _, segmentSnapshot := range ourSnapshot.segment {
-		if _, ok := segmentSnapshot.segment.(*zap.Segment); ok {
-			onlyZapSnapshots = append(onlyZapSnapshots, segmentSnapshot)
+		if _, ok := segmentSnapshot.segment.(segment.PersistedSegment); ok {
+			onlyPersistedSnapshots = append(onlyPersistedSnapshots, segmentSnapshot)
 		}
 	}
 
 	atomic.AddUint64(&s.stats.TotFileMergePlan, 1)
 
 	// give this list to the planner
-	resultMergePlan, err := mergeplan.Plan(onlyZapSnapshots, options)
+	resultMergePlan, err := mergeplan.Plan(onlyPersistedSnapshots, options)
 	if err != nil {
 		atomic.AddUint64(&s.stats.TotFileMergePlanErr, 1)
 		return fmt.Errorf("merge planning err: %v", err)
@@ -157,8 +156,8 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 	atomic.AddUint64(&s.stats.TotFileMergePlanTasks, uint64(len(resultMergePlan.Tasks)))
 
 	// process tasks in serial for now
-	var notifications []chan *IndexSnapshot
 	var filenames []string
+
 	for _, task := range resultMergePlan.Tasks {
 		if len(task.Segments) == 0 {
 			atomic.AddUint64(&s.stats.TotFileMergePlanTasksSegmentsEmpty, 1)
@@ -169,24 +168,24 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 
 		oldMap := make(map[uint64]*SegmentSnapshot)
 		newSegmentID := atomic.AddUint64(&s.nextSegmentID, 1)
-		segmentsToMerge := make([]*zap.Segment, 0, len(task.Segments))
+		segmentsToMerge := make([]segment.Segment, 0, len(task.Segments))
 		docsToDrop := make([]*roaring.Bitmap, 0, len(task.Segments))
 
 		for _, planSegment := range task.Segments {
 			if segSnapshot, ok := planSegment.(*SegmentSnapshot); ok {
 				oldMap[segSnapshot.id] = segSnapshot
-				if zapSeg, ok := segSnapshot.segment.(*zap.Segment); ok {
+				if persistedSeg, ok := segSnapshot.segment.(segment.PersistedSegment); ok {
 					if segSnapshot.LiveSize() == 0 {
 						atomic.AddUint64(&s.stats.TotFileMergeSegmentsEmpty, 1)
 						oldMap[segSnapshot.id] = nil
 					} else {
-						segmentsToMerge = append(segmentsToMerge, zapSeg)
+						segmentsToMerge = append(segmentsToMerge, segSnapshot.segment)
 						docsToDrop = append(docsToDrop, segSnapshot.deleted)
 					}
 					// track the files getting merged for unsetting the
 					// removal ineligibility. This helps to unflip files
 					// even with fast merger, slow persister work flows.
-					path := zapSeg.Path()
+					path := persistedSeg.Path()
 					filenames = append(filenames,
 						strings.TrimPrefix(path, s.path+string(os.PathSeparator)))
 				}
@@ -203,8 +202,8 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 			fileMergeZapStartTime := time.Now()
 
 			atomic.AddUint64(&s.stats.TotFileMergeZapBeg, 1)
-			newDocNums, _, err := zap.Merge(segmentsToMerge, docsToDrop, path,
-				DefaultChunkFactor, s.closeCh, s)
+			newDocNums, _, err := s.segPlugin.Merge(segmentsToMerge, docsToDrop, path,
+				s.closeCh, s)
 			atomic.AddUint64(&s.stats.TotFileMergeZapEnd, 1)
 
 			fileMergeZapTime := uint64(time.Since(fileMergeZapStartTime))
@@ -222,17 +221,12 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 				return fmt.Errorf("merging failed: %v", err)
 			}
 
-			seg, err = zap.Open(path)
+			seg, err = s.segPlugin.Open(path)
 			if err != nil {
 				s.unmarkIneligibleForRemoval(filename)
 				atomic.AddUint64(&s.stats.TotFileMergePlanTasksErr, 1)
 				return err
 			}
-			err = zap.ValidateMerge(segmentsToMerge, nil, docsToDrop, seg.(*zap.Segment))
-			if err != nil {
-				s.unmarkIneligibleForRemoval(filename)
-				return fmt.Errorf("merge validation failed: %v", err)
-			}
 			oldNewDocNums = make(map[uint64][]uint64)
 			for i, segNewDocNums := range newDocNums {
 				oldNewDocNums[task.Segments[i].Id()] = segNewDocNums
@@ -246,9 +240,8 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 			old:           oldMap,
 			oldNewDocNums: oldNewDocNums,
 			new:           seg,
-			notify:        make(chan *IndexSnapshot, 1),
+			notify:        make(chan *IndexSnapshot),
 		}
-		notifications = append(notifications, sm.notify)
 
 		// give it to the introducer
 		select {
@@ -259,20 +252,21 @@ func (s *Scorch) planMergeAtSnapshot(ourSnapshot *IndexSnapshot,
 			atomic.AddUint64(&s.stats.TotFileMergeIntroductions, 1)
 		}
 
-		atomic.AddUint64(&s.stats.TotFileMergePlanTasksDone, 1)
-	}
-
-	for _, notification := range notifications {
-		select {
-		case <-s.closeCh:
-			atomic.AddUint64(&s.stats.TotFileMergeIntroductionsSkipped, 1)
-			return segment.ErrClosed
-		case newSnapshot := <-notification:
-			atomic.AddUint64(&s.stats.TotFileMergeIntroductionsDone, 1)
-			if newSnapshot != nil {
-				_ = newSnapshot.DecRef()
-			}
+		introStartTime := time.Now()
+		// it is safe to blockingly wait for the merge introduction
+		// here as the introducer is bound to handle the notify channel.
+		newSnapshot := <-sm.notify
+		introTime := uint64(time.Since(introStartTime))
+		atomic.AddUint64(&s.stats.TotFileMergeZapIntroductionTime, introTime)
+		if atomic.LoadUint64(&s.stats.MaxFileMergeZapIntroductionTime) < introTime {
+			atomic.StoreUint64(&s.stats.MaxFileMergeZapIntroductionTime, introTime)
+		}
+		atomic.AddUint64(&s.stats.TotFileMergeIntroductionsDone, 1)
+		if newSnapshot != nil {
+			_ = newSnapshot.DecRef()
 		}
+
+		atomic.AddUint64(&s.stats.TotFileMergePlanTasksDone, 1)
 	}
 
 	// once all the newly merged segment introductions are done,
@@ -297,8 +291,8 @@ type segmentMerge struct {
 // persisted segment, and synchronously introduce that new segment
 // into the root
 func (s *Scorch) mergeSegmentBases(snapshot *IndexSnapshot,
-	sbs []*zap.SegmentBase, sbsDrops []*roaring.Bitmap, sbsIndexes []int,
-	chunkFactor uint32) (*IndexSnapshot, uint64, error) {
+	sbs []segment.Segment, sbsDrops []*roaring.Bitmap,
+	sbsIndexes []int) (*IndexSnapshot, uint64, error) {
 	atomic.AddUint64(&s.stats.TotMemMergeBeg, 1)
 
 	memMergeZapStartTime := time.Now()
@@ -310,7 +304,7 @@ func (s *Scorch) mergeSegmentBases(snapshot *IndexSnapshot,
 	path := s.path + string(os.PathSeparator) + filename
 
 	newDocNums, _, err :=
-		zap.MergeSegmentBases(sbs, sbsDrops, path, chunkFactor, s.closeCh, s)
+		s.segPlugin.Merge(sbs, sbsDrops, path, s.closeCh, s)
 
 	atomic.AddUint64(&s.stats.TotMemMergeZapEnd, 1)
 
@@ -325,15 +319,11 @@ func (s *Scorch) mergeSegmentBases(snapshot *IndexSnapshot,
 		return nil, 0, err
 	}
 
-	seg, err := zap.Open(path)
+	seg, err := s.segPlugin.Open(path)
 	if err != nil {
 		atomic.AddUint64(&s.stats.TotMemMergeErr, 1)
 		return nil, 0, err
 	}
-	err = zap.ValidateMerge(nil, sbs, sbsDrops, seg.(*zap.Segment))
-	if err != nil {
-		return nil, 0, fmt.Errorf("in-memory merge validation failed: %v", err)
-	}
 
 	// update persisted stats
 	atomic.AddUint64(&s.stats.TotPersistedItems, seg.Count())
@@ -344,7 +334,7 @@ func (s *Scorch) mergeSegmentBases(snapshot *IndexSnapshot,
 		old:           make(map[uint64]*SegmentSnapshot),
 		oldNewDocNums: make(map[uint64][]uint64),
 		new:           seg,
-		notify:        make(chan *IndexSnapshot, 1),
+		notify:        make(chan *IndexSnapshot),
 	}
 
 	for i, idx := range sbsIndexes {
@@ -360,14 +350,13 @@ func (s *Scorch) mergeSegmentBases(snapshot *IndexSnapshot,
 	case s.merges <- sm:
 	}
 
-	select { // wait for introduction to complete
-	case <-s.closeCh:
-		return nil, 0, segment.ErrClosed
-	case newSnapshot := <-sm.notify:
+	// blockingly wait for the introduction to complete
+	newSnapshot := <-sm.notify
+	if newSnapshot != nil {
 		atomic.AddUint64(&s.stats.TotMemMergeSegments, uint64(len(sbs)))
 		atomic.AddUint64(&s.stats.TotMemMergeDone, 1)
-		return newSnapshot, newSegmentID, nil
 	}
+	return newSnapshot, newSegmentID, nil
 }
 
 func (s *Scorch) ReportBytesWritten(bytesWritten uint64) {
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/optimize.go b/vendor/github.com/blevesearch/bleve/index/scorch/optimize.go
index b33e3be3d4..b9cb9228af 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/optimize.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/optimize.go
@@ -18,10 +18,8 @@ import (
 	"fmt"
 
 	"github.com/RoaringBitmap/roaring"
-
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	"github.com/blevesearch/bleve/index/scorch/segment/zap"
 )
 
 var OptimizeConjunction = true
@@ -81,25 +79,25 @@ func (o *OptimizeTFRConjunction) Finish() (index.Optimized, error) {
 	}
 
 	for i := range o.snapshot.segment {
-		itr0, ok := o.tfrs[0].iterators[i].(*zap.PostingsIterator)
-		if !ok || itr0.ActualBM == nil {
+		itr0, ok := o.tfrs[0].iterators[i].(segment.OptimizablePostingsIterator)
+		if !ok || itr0.ActualBitmap() == nil {
 			continue
 		}
 
-		itr1, ok := o.tfrs[1].iterators[i].(*zap.PostingsIterator)
-		if !ok || itr1.ActualBM == nil {
+		itr1, ok := o.tfrs[1].iterators[i].(segment.OptimizablePostingsIterator)
+		if !ok || itr1.ActualBitmap() == nil {
 			continue
 		}
 
-		bm := roaring.And(itr0.ActualBM, itr1.ActualBM)
+		bm := roaring.And(itr0.ActualBitmap(), itr1.ActualBitmap())
 
 		for _, tfr := range o.tfrs[2:] {
-			itr, ok := tfr.iterators[i].(*zap.PostingsIterator)
-			if !ok || itr.ActualBM == nil {
+			itr, ok := tfr.iterators[i].(segment.OptimizablePostingsIterator)
+			if !ok || itr.ActualBitmap() == nil {
 				continue
 			}
 
-			bm.And(itr.ActualBM)
+			bm.And(itr.ActualBitmap())
 		}
 
 		// in this conjunction optimization, the postings iterators
@@ -107,10 +105,9 @@ func (o *OptimizeTFRConjunction) Finish() (index.Optimized, error) {
 		// regular conjunction searcher machinery will still be used,
 		// but the underlying bitmap will be smaller.
 		for _, tfr := range o.tfrs {
-			itr, ok := tfr.iterators[i].(*zap.PostingsIterator)
-			if ok && itr.ActualBM != nil {
-				itr.ActualBM = bm
-				itr.Actual = bm.Iterator()
+			itr, ok := tfr.iterators[i].(segment.OptimizablePostingsIterator)
+			if ok && itr.ActualBitmap() != nil {
+				itr.ReplaceActual(bm)
 			}
 		}
 	}
@@ -191,9 +188,9 @@ OUTER:
 				continue OUTER
 			}
 
-			itr, ok := tfr.iterators[i].(*zap.PostingsIterator)
+			itr, ok := tfr.iterators[i].(segment.OptimizablePostingsIterator)
 			if !ok {
-				// We optimize zap postings iterators only.
+				// We only optimize postings iterators that support this operation.
 				return nil, nil
 			}
 
@@ -201,12 +198,6 @@ OUTER:
 			// can perform several optimizations up-front here.
 			docNum1Hit, ok := itr.DocNum1Hit()
 			if ok {
-				if docNum1Hit == zap.DocNum1HitFinished {
-					// An empty docNum here means the entire AND is empty.
-					oTFR.iterators[i] = segment.AnEmptyPostingsIterator
-					continue OUTER
-				}
-
 				if docNum1HitLastOk && docNum1HitLast != docNum1Hit {
 					// The docNum1Hit doesn't match the previous
 					// docNum1HitLast, so the entire AND is empty.
@@ -220,14 +211,14 @@ OUTER:
 				continue
 			}
 
-			if itr.ActualBM == nil {
+			if itr.ActualBitmap() == nil {
 				// An empty actual bitmap means the entire AND is empty.
 				oTFR.iterators[i] = segment.AnEmptyPostingsIterator
 				continue OUTER
 			}
 
 			// Collect the actual bitmap for more processing later.
-			actualBMs = append(actualBMs, itr.ActualBM)
+			actualBMs = append(actualBMs, itr.ActualBitmap())
 		}
 
 		if docNum1HitLastOk {
@@ -245,11 +236,7 @@ OUTER:
 
 			// The actual bitmaps and docNum1Hits all contain or have
 			// the same 1-hit docNum, so that's our AND'ed result.
-			oTFR.iterators[i], err = zap.PostingsIteratorFrom1Hit(
-				docNum1HitLast, zap.NormBits1Hit, false, false)
-			if err != nil {
-				return nil, nil
-			}
+			oTFR.iterators[i] = segment.NewUnadornedPostingsIteratorFrom1Hit(docNum1HitLast)
 
 			continue OUTER
 		}
@@ -263,11 +250,7 @@ OUTER:
 
 		if len(actualBMs) == 1 {
 			// If we've only 1 actual bitmap, then that's our result.
-			oTFR.iterators[i], err = zap.PostingsIteratorFromBitmap(
-				actualBMs[0], false, false)
-			if err != nil {
-				return nil, nil
-			}
+			oTFR.iterators[i] = segment.NewUnadornedPostingsIteratorFromBitmap(actualBMs[0])
 
 			continue OUTER
 		}
@@ -279,11 +262,7 @@ OUTER:
 			bm.And(actualBM)
 		}
 
-		oTFR.iterators[i], err = zap.PostingsIteratorFromBitmap(
-			bm, false, false)
-		if err != nil {
-			return nil, nil
-		}
+		oTFR.iterators[i] = segment.NewUnadornedPostingsIteratorFromBitmap(bm)
 	}
 
 	return oTFR, nil
@@ -337,13 +316,13 @@ func (o *OptimizeTFRDisjunctionUnadorned) Finish() (rv index.Optimized, err erro
 		var cMax uint64
 
 		for _, tfr := range o.tfrs {
-			itr, ok := tfr.iterators[i].(*zap.PostingsIterator)
+			itr, ok := tfr.iterators[i].(segment.OptimizablePostingsIterator)
 			if !ok {
 				return nil, nil
 			}
 
-			if itr.ActualBM != nil {
-				c := itr.ActualBM.GetCardinality()
+			if itr.ActualBitmap() != nil {
+				c := itr.ActualBitmap().GetCardinality()
 				if cMax < c {
 					cMax = c
 				}
@@ -379,7 +358,7 @@ func (o *OptimizeTFRDisjunctionUnadorned) Finish() (rv index.Optimized, err erro
 		actualBMs = actualBMs[:0]
 
 		for _, tfr := range o.tfrs {
-			itr, ok := tfr.iterators[i].(*zap.PostingsIterator)
+			itr, ok := tfr.iterators[i].(segment.OptimizablePostingsIterator)
 			if !ok {
 				return nil, nil
 			}
@@ -390,8 +369,8 @@ func (o *OptimizeTFRDisjunctionUnadorned) Finish() (rv index.Optimized, err erro
 				continue
 			}
 
-			if itr.ActualBM != nil {
-				actualBMs = append(actualBMs, itr.ActualBM)
+			if itr.ActualBitmap() != nil {
+				actualBMs = append(actualBMs, itr.ActualBitmap())
 			}
 		}
 
@@ -410,10 +389,7 @@ func (o *OptimizeTFRDisjunctionUnadorned) Finish() (rv index.Optimized, err erro
 
 		bm.AddMany(docNums)
 
-		oTFR.iterators[i], err = zap.PostingsIteratorFromBitmap(bm, false, false)
-		if err != nil {
-			return nil, nil
-		}
+		oTFR.iterators[i] = segment.NewUnadornedPostingsIteratorFromBitmap(bm)
 	}
 
 	return oTFR, nil
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/persister.go b/vendor/github.com/blevesearch/bleve/index/scorch/persister.go
index 064e9e6a85..30e75df77f 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/persister.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/persister.go
@@ -32,12 +32,9 @@ import (
 	"github.com/RoaringBitmap/roaring"
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	"github.com/blevesearch/bleve/index/scorch/segment/zap"
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
-var DefaultChunkFactor uint32 = 1024
-
 // DefaultPersisterNapTimeMSec is kept to zero as this helps in direct
 // persistence of segments with the default safe batch option.
 // If the default safe batch option results in high number of
@@ -253,7 +250,7 @@ func (s *Scorch) pausePersisterForMergerCatchUp(lastPersistedEpoch uint64,
 	persistWatchers = notifyMergeWatchers(lastPersistedEpoch, persistWatchers)
 
 	// Check the merger lag by counting the segment files on disk,
-	numFilesOnDisk, _ := s.diskFileStats()
+	numFilesOnDisk, _, _ := s.diskFileStats(nil)
 
 	// On finding fewer files on disk, persister takes a short pause
 	// for sufficient in-memory segments to pile up for the next
@@ -280,7 +277,7 @@ func (s *Scorch) pausePersisterForMergerCatchUp(lastPersistedEpoch uint64,
 	// 2. The merger could be lagging behind on merging the disk files.
 	if numFilesOnDisk > uint64(po.PersisterNapUnderNumFiles) {
 		s.removeOldData()
-		numFilesOnDisk, _ = s.diskFileStats()
+		numFilesOnDisk, _, _ = s.diskFileStats(nil)
 	}
 
 	// Persister pause until the merger catches up to reduce the segment
@@ -305,7 +302,7 @@ OUTER:
 		// let the watchers proceed if they lag behind
 		persistWatchers = notifyMergeWatchers(lastPersistedEpoch, persistWatchers)
 
-		numFilesOnDisk, _ = s.diskFileStats()
+		numFilesOnDisk, _, _ = s.diskFileStats(nil)
 	}
 
 	return lastMergedEpoch, persistWatchers
@@ -360,13 +357,13 @@ var DefaultMinSegmentsForInMemoryMerge = 2
 func (s *Scorch) persistSnapshotMaybeMerge(snapshot *IndexSnapshot) (
 	bool, error) {
 	// collect the in-memory zap segments (SegmentBase instances)
-	var sbs []*zap.SegmentBase
+	var sbs []segment.Segment
 	var sbsDrops []*roaring.Bitmap
 	var sbsIndexes []int
 
 	for i, segmentSnapshot := range snapshot.segment {
-		if sb, ok := segmentSnapshot.segment.(*zap.SegmentBase); ok {
-			sbs = append(sbs, sb)
+		if _, ok := segmentSnapshot.segment.(segment.PersistedSegment); !ok {
+			sbs = append(sbs, segmentSnapshot.segment)
 			sbsDrops = append(sbsDrops, segmentSnapshot.deleted)
 			sbsIndexes = append(sbsIndexes, i)
 		}
@@ -377,7 +374,7 @@ func (s *Scorch) persistSnapshotMaybeMerge(snapshot *IndexSnapshot) (
 	}
 
 	newSnapshot, newSegmentID, err := s.mergeSegmentBases(
-		snapshot, sbs, sbsDrops, sbsIndexes, DefaultChunkFactor)
+		snapshot, sbs, sbsDrops, sbsIndexes)
 	if err != nil {
 		return false, err
 	}
@@ -459,13 +456,13 @@ func (s *Scorch) persistSnapshotDirect(snapshot *IndexSnapshot) (err error) {
 	if err != nil {
 		return err
 	}
-	err = metaBucket.Put([]byte("type"), []byte(zap.Type))
+	err = metaBucket.Put(boltMetaDataSegmentTypeKey, []byte(s.segPlugin.Type()))
 	if err != nil {
 		return err
 	}
 	buf := make([]byte, binary.MaxVarintLen32)
-	binary.BigEndian.PutUint32(buf, zap.Version)
-	err = metaBucket.Put([]byte("version"), buf)
+	binary.BigEndian.PutUint32(buf, s.segPlugin.Version())
+	err = metaBucket.Put(boltMetaDataSegmentVersionKey, buf)
 	if err != nil {
 		return err
 	}
@@ -494,11 +491,19 @@ func (s *Scorch) persistSnapshotDirect(snapshot *IndexSnapshot) (err error) {
 			return err
 		}
 		switch seg := segmentSnapshot.segment.(type) {
-		case *zap.SegmentBase:
+		case segment.PersistedSegment:
+			path := seg.Path()
+			filename := strings.TrimPrefix(path, s.path+string(os.PathSeparator))
+			err = snapshotSegmentBucket.Put(boltPathKey, []byte(filename))
+			if err != nil {
+				return err
+			}
+			filenames = append(filenames, filename)
+		case segment.UnpersistedSegment:
 			// need to persist this to disk
 			filename := zapFileName(segmentSnapshot.id)
 			path := s.path + string(os.PathSeparator) + filename
-			err = zap.PersistSegmentBase(seg, path)
+			err = seg.Persist(path)
 			if err != nil {
 				return fmt.Errorf("error persisting segment: %v", err)
 			}
@@ -508,14 +513,7 @@ func (s *Scorch) persistSnapshotDirect(snapshot *IndexSnapshot) (err error) {
 				return err
 			}
 			filenames = append(filenames, filename)
-		case *zap.Segment:
-			path := seg.Path()
-			filename := strings.TrimPrefix(path, s.path+string(os.PathSeparator))
-			err = snapshotSegmentBucket.Put(boltPathKey, []byte(filename))
-			if err != nil {
-				return err
-			}
-			filenames = append(filenames, filename)
+
 		default:
 			return fmt.Errorf("unknown segment type: %T", seg)
 		}
@@ -553,7 +551,7 @@ func (s *Scorch) persistSnapshotDirect(snapshot *IndexSnapshot) (err error) {
 			}
 		}()
 		for segmentID, path := range newSegmentPaths {
-			newSegments[segmentID], err = zap.Open(path)
+			newSegments[segmentID], err = s.segPlugin.Open(path)
 			if err != nil {
 				return fmt.Errorf("error opening new segment at %s, %v", path, err)
 			}
@@ -609,6 +607,8 @@ var boltPathKey = []byte{'p'}
 var boltDeletedKey = []byte{'d'}
 var boltInternalKey = []byte{'i'}
 var boltMetaDataKey = []byte{'m'}
+var boltMetaDataSegmentTypeKey = []byte("type")
+var boltMetaDataSegmentVersionKey = []byte("version")
 
 func (s *Scorch) loadFromBolt() error {
 	return s.rootBolt.View(func(tx *bolt.Tx) error {
@@ -693,6 +693,23 @@ func (s *Scorch) loadSnapshot(snapshot *bolt.Bucket) (*IndexSnapshot, error) {
 		refs:     1,
 		creator:  "loadSnapshot",
 	}
+	// first we look for the meta-data bucket, this will tell us
+	// which segment type/version was used for this snapshot
+	// all operations for this scorch will use this type/version
+	metaBucket := snapshot.Bucket(boltMetaDataKey)
+	if metaBucket == nil {
+		_ = rv.DecRef()
+		return nil, fmt.Errorf("meta-data bucket missing")
+	}
+	segmentType := string(metaBucket.Get(boltMetaDataSegmentTypeKey))
+	segmentVersion := binary.BigEndian.Uint32(
+		metaBucket.Get(boltMetaDataSegmentVersionKey))
+	err := s.loadSegmentPlugin(segmentType, segmentVersion)
+	if err != nil {
+		_ = rv.DecRef()
+		return nil, fmt.Errorf(
+			"unable to load correct segment wrapper: %v", err)
+	}
 	var running uint64
 	c := snapshot.Cursor()
 	for k, _ := c.First(); k != nil; k, _ = c.Next() {
@@ -737,7 +754,7 @@ func (s *Scorch) loadSegment(segmentBucket *bolt.Bucket) (*SegmentSnapshot, erro
 		return nil, fmt.Errorf("segment path missing")
 	}
 	segmentPath := s.path + string(os.PathSeparator) + string(pathBytes)
-	segment, err := zap.Open(segmentPath)
+	segment, err := s.segPlugin.Open(segmentPath)
 	if err != nil {
 		return nil, fmt.Errorf("error opening bolt segment: %v", err)
 	}
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/scorch.go b/vendor/github.com/blevesearch/bleve/index/scorch/scorch.go
index 44a97d1ea6..80f9e3a797 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/scorch.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/scorch.go
@@ -28,10 +28,9 @@ import (
 	"github.com/blevesearch/bleve/document"
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	"github.com/blevesearch/bleve/index/scorch/segment/zap"
 	"github.com/blevesearch/bleve/index/store"
 	"github.com/blevesearch/bleve/registry"
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 const Name = "scorch"
@@ -67,7 +66,6 @@ type Scorch struct {
 	persists           chan *persistIntroduction
 	merges             chan *segmentMerge
 	introducerNotifier chan *epochWatcher
-	revertToSnapshots  chan *snapshotReversion
 	persisterNotifier  chan *epochWatcher
 	rootBolt           *bolt.DB
 	asyncTasks         sync.WaitGroup
@@ -78,6 +76,8 @@ type Scorch struct {
 	pauseLock sync.RWMutex
 
 	pauseCount uint64
+
+	segPlugin segment.Plugin
 }
 
 type internalStats struct {
@@ -101,7 +101,25 @@ func NewScorch(storeName string,
 		nextSnapshotEpoch:    1,
 		closeCh:              make(chan struct{}),
 		ineligibleForRemoval: map[string]bool{},
+		segPlugin:            defaultSegmentPlugin,
+	}
+
+	// check if the caller has requested a specific segment type/version
+	forcedSegmentVersion, ok := config["forceSegmentVersion"].(int)
+	if ok {
+		forcedSegmentType, ok2 := config["forceSegmentType"].(string)
+		if !ok2 {
+			return nil, fmt.Errorf(
+				"forceSegmentVersion set to %d, must also specify forceSegmentType", forcedSegmentVersion)
+		}
+
+		err := rv.loadSegmentPlugin(forcedSegmentType,
+			uint32(forcedSegmentVersion))
+		if err != nil {
+			return nil, err
+		}
 	}
+
 	rv.root = &IndexSnapshot{parent: rv, refs: 1, creator: "NewScorch"}
 	ro, ok := config["read_only"].(bool)
 	if ok {
@@ -221,8 +239,8 @@ func (s *Scorch) openBolt() error {
 	s.persists = make(chan *persistIntroduction)
 	s.merges = make(chan *segmentMerge)
 	s.introducerNotifier = make(chan *epochWatcher, 1)
-	s.revertToSnapshots = make(chan *snapshotReversion)
 	s.persisterNotifier = make(chan *epochWatcher, 1)
+	s.closeCh = make(chan struct{})
 
 	if !s.readOnly && s.path != "" {
 		err := s.removeOldZapFiles() // Before persister or merger create any new files.
@@ -263,7 +281,10 @@ func (s *Scorch) Close() (err error) {
 		err = s.rootBolt.Close()
 		s.rootLock.Lock()
 		if s.root != nil {
-			_ = s.root.DecRef()
+			err2 := s.root.DecRef()
+			if err == nil {
+				err = err2
+			}
 		}
 		s.root = nil
 		s.rootLock.Unlock()
@@ -349,7 +370,7 @@ func (s *Scorch) Batch(batch *index.Batch) (err error) {
 	var newSegment segment.Segment
 	var bufBytes uint64
 	if len(analysisResults) > 0 {
-		newSegment, bufBytes, err = zap.AnalysisResultsToSegmentBase(analysisResults, DefaultChunkFactor)
+		newSegment, bufBytes, err = s.segPlugin.New(analysisResults)
 		if err != nil {
 			return err
 		}
@@ -466,8 +487,9 @@ func (s *Scorch) Stats() json.Marshaler {
 	return &s.stats
 }
 
-func (s *Scorch) diskFileStats() (uint64, uint64) {
-	var numFilesOnDisk, numBytesUsedDisk uint64
+func (s *Scorch) diskFileStats(rootSegmentPaths map[string]struct{}) (uint64,
+	uint64, uint64) {
+	var numFilesOnDisk, numBytesUsedDisk, numBytesOnDiskByRoot uint64
 	if s.path != "" {
 		finfos, err := ioutil.ReadDir(s.path)
 		if err == nil {
@@ -475,24 +497,47 @@ func (s *Scorch) diskFileStats() (uint64, uint64) {
 				if !finfo.IsDir() {
 					numBytesUsedDisk += uint64(finfo.Size())
 					numFilesOnDisk++
+					if rootSegmentPaths != nil {
+						fname := s.path + string(os.PathSeparator) + finfo.Name()
+						if _, fileAtRoot := rootSegmentPaths[fname]; fileAtRoot {
+							numBytesOnDiskByRoot += uint64(finfo.Size())
+						}
+					}
 				}
 			}
 		}
 	}
-	return numFilesOnDisk, numBytesUsedDisk
+	// if no root files path given, then consider all disk files.
+	if rootSegmentPaths == nil {
+		return numFilesOnDisk, numBytesUsedDisk, numBytesUsedDisk
+	}
+
+	return numFilesOnDisk, numBytesUsedDisk, numBytesOnDiskByRoot
+}
+
+func (s *Scorch) rootDiskSegmentsPaths() map[string]struct{} {
+	rv := make(map[string]struct{}, len(s.root.segment))
+	for _, segmentSnapshot := range s.root.segment {
+		if seg, ok := segmentSnapshot.segment.(segment.PersistedSegment); ok {
+			rv[seg.Path()] = struct{}{}
+		}
+	}
+	return rv
 }
 
 func (s *Scorch) StatsMap() map[string]interface{} {
 	m := s.stats.ToMap()
 
-	numFilesOnDisk, numBytesUsedDisk := s.diskFileStats()
+	s.rootLock.RLock()
+	rootSegPaths := s.rootDiskSegmentsPaths()
+	m["CurFilesIneligibleForRemoval"] = uint64(len(s.ineligibleForRemoval))
+	s.rootLock.RUnlock()
+
+	numFilesOnDisk, numBytesUsedDisk, numBytesOnDiskByRoot := s.diskFileStats(rootSegPaths)
 
 	m["CurOnDiskBytes"] = numBytesUsedDisk
 	m["CurOnDiskFiles"] = numFilesOnDisk
 
-	s.rootLock.RLock()
-	m["CurFilesIneligibleForRemoval"] = uint64(len(s.ineligibleForRemoval))
-	s.rootLock.RUnlock()
 	// TODO: consider one day removing these backwards compatible
 	// names for apps using the old names
 	m["updates"] = m["TotUpdates"]
@@ -507,8 +552,11 @@ func (s *Scorch) StatsMap() map[string]interface{} {
 	m["num_items_introduced"] = m["TotIntroducedItems"]
 	m["num_items_persisted"] = m["TotPersistedItems"]
 	m["num_recs_to_persist"] = m["TotItemsToPersist"]
-	m["num_bytes_used_disk"] = m["CurOnDiskBytes"]
-	m["num_files_on_disk"] = m["CurOnDiskFiles"]
+	// total disk bytes found in index directory inclusive of older snapshots
+	m["num_bytes_used_disk"] = numBytesUsedDisk
+	// total disk bytes by the latest root index, exclusive of older snapshots
+	m["num_bytes_used_disk_by_root"] = numBytesOnDiskByRoot
+	m["num_files_on_disk"] = numFilesOnDisk
 	m["num_root_memorysegments"] = m["TotMemorySegmentsAtRoot"]
 	m["num_root_filesegments"] = m["TotFileSegmentsAtRoot"]
 	m["num_persister_nap_pause_completed"] = m["TotPersisterNapPauseCompleted"]
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/empty.go b/vendor/github.com/blevesearch/bleve/index/scorch/segment/empty.go
index fdc407a747..340db73a67 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/empty.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/segment/empty.go
@@ -105,10 +105,6 @@ func (e *EmptyDictionaryIterator) Contains(key []byte) (bool, error) {
 	return false, nil
 }
 
-func (e *EmptyPostingsIterator) Advance(uint64) (Posting, error) {
-	return nil, nil
-}
-
 type EmptyPostingsList struct{}
 
 func (e *EmptyPostingsList) Iterator(includeFreq, includeNorm, includeLocations bool,
@@ -130,6 +126,10 @@ func (e *EmptyPostingsIterator) Next() (Posting, error) {
 	return nil, nil
 }
 
+func (e *EmptyPostingsIterator) Advance(uint64) (Posting, error) {
+	return nil, nil
+}
+
 func (e *EmptyPostingsIterator) Size() int {
 	return 0
 }
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/plugin.go b/vendor/github.com/blevesearch/bleve/index/scorch/segment/plugin.go
new file mode 100644
index 0000000000..d8aaa0b6d1
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/segment/plugin.go
@@ -0,0 +1,58 @@
+//  Copyright (c) 2020 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package segment
+
+import (
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/index"
+)
+
+// Plugin represents the essential functions required by a package to plug in
+// it's segment implementation
+type Plugin interface {
+
+	// Type is the name for this segment plugin
+	Type() string
+
+	// Version is a numeric value identifying a specific version of this type.
+	// When incompatible changes are made to a particular type of plugin, the
+	// version must be incremented.
+	Version() uint32
+
+	// New takes a set of AnalysisResults and turns them into a new Segment
+	New(results []*index.AnalysisResult) (Segment, uint64, error)
+
+	// Open attempts to open the file at the specified path and
+	// return the corresponding Segment
+	Open(path string) (Segment, error)
+
+	// Merge takes a set of Segments, and creates a new segment on disk at
+	// the specified path.
+	// Drops is a set of bitmaps (one for each segment) indicating which
+	// documents can be dropped from the segments during the merge.
+	// If the closeCh channel is closed, Merge will cease doing work at
+	// the next opportunity, and return an error (closed).
+	// StatsReporter can optionally be provided, in which case progress
+	// made during the merge is reported while operation continues.
+	// Returns:
+	// A slice of new document numbers (one for each input segment),
+	// this allows the caller to know a particular document's new
+	// document number in the newly merged segment.
+	// The number of bytes written to the new segment file.
+	// An error, if any occurred.
+	Merge(segments []Segment, drops []*roaring.Bitmap, path string,
+		closeCh chan struct{}, s StatsReporter) (
+		[][]uint64, uint64, error)
+}
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/segment.go b/vendor/github.com/blevesearch/bleve/index/scorch/segment/segment.go
index 34c2bc2048..ddd0d09102 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/segment.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/segment/segment.go
@@ -50,6 +50,16 @@ type Segment interface {
 	DecRef() error
 }
 
+type UnpersistedSegment interface {
+	Segment
+	Persist(path string) error
+}
+
+type PersistedSegment interface {
+	Segment
+	Path() string
+}
+
 type TermDictionary interface {
 	PostingsList(term []byte, except *roaring.Bitmap, prealloc PostingsList) (PostingsList, error)
 
@@ -96,6 +106,12 @@ type PostingsIterator interface {
 	Size() int
 }
 
+type OptimizablePostingsIterator interface {
+	ActualBitmap() *roaring.Bitmap
+	DocNum1Hit() (uint64, bool)
+	ReplaceActual(*roaring.Bitmap)
+}
+
 type Posting interface {
 	Number() uint64
 
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/unadorned.go b/vendor/github.com/blevesearch/bleve/index/scorch/segment/unadorned.go
new file mode 100644
index 0000000000..9a4d6c76c9
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/segment/unadorned.go
@@ -0,0 +1,148 @@
+//  Copyright (c) 2020 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package segment
+
+import (
+	"github.com/RoaringBitmap/roaring"
+	"math"
+	"reflect"
+)
+
+var reflectStaticSizeUnadornedPostingsIteratorBitmap int
+var reflectStaticSizeUnadornedPostingsIterator1Hit int
+var reflectStaticSizeUnadornedPosting int
+
+
+func init() {
+	var pib UnadornedPostingsIteratorBitmap
+	reflectStaticSizeUnadornedPostingsIteratorBitmap = int(reflect.TypeOf(pib).Size())
+	var pi1h UnadornedPostingsIterator1Hit
+	reflectStaticSizeUnadornedPostingsIterator1Hit = int(reflect.TypeOf(pi1h).Size())
+	var up UnadornedPosting
+	reflectStaticSizeUnadornedPosting = int(reflect.TypeOf(up).Size())
+}
+
+type UnadornedPostingsIteratorBitmap struct{
+	actual   roaring.IntPeekable
+	actualBM *roaring.Bitmap
+}
+
+func (i *UnadornedPostingsIteratorBitmap) Next() (Posting, error) {
+	return i.nextAtOrAfter(0)
+}
+
+func (i *UnadornedPostingsIteratorBitmap) Advance(docNum uint64) (Posting, error) {
+	return i.nextAtOrAfter(docNum)
+}
+
+func (i *UnadornedPostingsIteratorBitmap) nextAtOrAfter(atOrAfter uint64) (Posting, error) {
+	docNum, exists := i.nextDocNumAtOrAfter(atOrAfter)
+	if !exists {
+		return nil, nil
+	}
+	return UnadornedPosting(docNum), nil
+}
+
+func (i *UnadornedPostingsIteratorBitmap) nextDocNumAtOrAfter(atOrAfter uint64) (uint64, bool) {
+	if i.actual == nil || !i.actual.HasNext() {
+		return 0, false
+	}
+	i.actual.AdvanceIfNeeded(uint32(atOrAfter))
+
+	if !i.actual.HasNext() {
+		return 0, false // couldn't find anything
+	}
+
+	return uint64(i.actual.Next()), true
+}
+
+func (i *UnadornedPostingsIteratorBitmap) Size() int {
+	return reflectStaticSizeUnadornedPostingsIteratorBitmap
+}
+
+func NewUnadornedPostingsIteratorFromBitmap(bm *roaring.Bitmap) PostingsIterator {
+	return &UnadornedPostingsIteratorBitmap{
+		actualBM: bm,
+		actual: bm.Iterator(),
+	}
+}
+
+const docNum1HitFinished = math.MaxUint64
+
+type UnadornedPostingsIterator1Hit struct{
+	docNum uint64
+}
+
+func (i *UnadornedPostingsIterator1Hit) Next() (Posting, error) {
+	return i.nextAtOrAfter(0)
+}
+
+func (i *UnadornedPostingsIterator1Hit) Advance(docNum uint64) (Posting, error) {
+	return i.nextAtOrAfter(docNum)
+}
+
+func (i *UnadornedPostingsIterator1Hit) nextAtOrAfter(atOrAfter uint64) (Posting, error) {
+	docNum, exists := i.nextDocNumAtOrAfter(atOrAfter)
+	if !exists {
+		return nil, nil
+	}
+	return UnadornedPosting(docNum), nil
+}
+
+func (i *UnadornedPostingsIterator1Hit) nextDocNumAtOrAfter(atOrAfter uint64) (uint64, bool) {
+	if i.docNum == docNum1HitFinished {
+		return 0, false
+	}
+	if i.docNum < atOrAfter {
+		// advanced past our 1-hit
+		i.docNum = docNum1HitFinished // consume our 1-hit docNum
+		return 0, false
+	}
+	docNum := i.docNum
+	i.docNum = docNum1HitFinished // consume our 1-hit docNum
+	return docNum, true
+}
+
+func (i *UnadornedPostingsIterator1Hit) Size() int {
+	return reflectStaticSizeUnadornedPostingsIterator1Hit
+}
+
+func NewUnadornedPostingsIteratorFrom1Hit(docNum1Hit uint64) PostingsIterator {
+	return &UnadornedPostingsIterator1Hit{
+		docNum1Hit,
+	}
+}
+
+type UnadornedPosting uint64
+
+func (p UnadornedPosting) Number() uint64 {
+	return uint64(p)
+}
+
+func (p UnadornedPosting) Frequency() uint64 {
+	return 0
+}
+
+func (p UnadornedPosting) Norm() float64 {
+	return 0
+}
+
+func (p UnadornedPosting) Locations() []Location {
+	return nil
+}
+
+func (p UnadornedPosting) Size() int {
+	return reflectStaticSizeUnadornedPosting
+}
\ No newline at end of file
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment_plugin.go b/vendor/github.com/blevesearch/bleve/index/scorch/segment_plugin.go
new file mode 100644
index 0000000000..01eda7fbd5
--- /dev/null
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/segment_plugin.go
@@ -0,0 +1,77 @@
+//  Copyright (c) 2019 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package scorch
+
+import (
+	"fmt"
+
+	"github.com/blevesearch/bleve/index/scorch/segment"
+
+	zapv11 "github.com/blevesearch/zap/v11"
+	zapv12 "github.com/blevesearch/zap/v12"
+)
+
+var supportedSegmentPlugins map[string]map[uint32]segment.Plugin
+var defaultSegmentPlugin segment.Plugin
+
+func init() {
+	ResetPlugins()
+	RegisterPlugin(zapv12.Plugin(), false)
+	RegisterPlugin(zapv11.Plugin(), true)
+}
+
+func ResetPlugins() {
+	supportedSegmentPlugins = map[string]map[uint32]segment.Plugin{}
+}
+
+func RegisterPlugin(plugin segment.Plugin, makeDefault bool) {
+	if _, ok := supportedSegmentPlugins[plugin.Type()]; !ok {
+		supportedSegmentPlugins[plugin.Type()] = map[uint32]segment.Plugin{}
+	}
+	supportedSegmentPlugins[plugin.Type()][plugin.Version()] = plugin
+	if makeDefault {
+		defaultSegmentPlugin = plugin
+	}
+}
+
+func SupportedSegmentTypes() (rv []string) {
+	for k := range supportedSegmentPlugins {
+		rv = append(rv, k)
+	}
+	return
+}
+
+func SupportedSegmentTypeVersions(typ string) (rv []uint32) {
+	for k := range supportedSegmentPlugins[typ] {
+		rv = append(rv, k)
+	}
+	return rv
+}
+
+func (s *Scorch) loadSegmentPlugin(forcedSegmentType string,
+	forcedSegmentVersion uint32) error {
+	if versions, ok := supportedSegmentPlugins[forcedSegmentType]; ok {
+		if segPlugin, ok := versions[uint32(forcedSegmentVersion)]; ok {
+			s.segPlugin = segPlugin
+			return nil
+		}
+		return fmt.Errorf(
+			"unsupported version %d for segment type: %s, supported: %v",
+			forcedSegmentVersion, forcedSegmentType,
+			SupportedSegmentTypeVersions(forcedSegmentType))
+	}
+	return fmt.Errorf("unsupported segment type: %s, supported: %v",
+		forcedSegmentType, SupportedSegmentTypes())
+}
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/snapshot_rollback.go b/vendor/github.com/blevesearch/bleve/index/scorch/snapshot_rollback.go
index 470868d0eb..7cc87bdea0 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/snapshot_rollback.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/snapshot_rollback.go
@@ -17,9 +17,10 @@ package scorch
 import (
 	"fmt"
 	"log"
+	"os"
 
 	"github.com/blevesearch/bleve/index/scorch/segment"
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 type RollbackPoint struct {
@@ -34,13 +35,22 @@ func (r *RollbackPoint) GetInternal(key []byte) []byte {
 // RollbackPoints returns an array of rollback points available for
 // the application to rollback to, with more recent rollback points
 // (higher epochs) coming first.
-func (s *Scorch) RollbackPoints() ([]*RollbackPoint, error) {
-	if s.rootBolt == nil {
-		return nil, fmt.Errorf("RollbackPoints: root is nil")
+func RollbackPoints(path string) ([]*RollbackPoint, error) {
+	if len(path) == 0 {
+		return nil, fmt.Errorf("RollbackPoints: invalid path")
+	}
+
+	rootBoltPath := path + string(os.PathSeparator) + "root.bolt"
+	rootBoltOpt := &bolt.Options{
+		ReadOnly: true,
+	}
+	rootBolt, err := bolt.Open(rootBoltPath, 0600, rootBoltOpt)
+	if err != nil || rootBolt == nil {
+		return nil, err
 	}
 
 	// start a read-only bolt transaction
-	tx, err := s.rootBolt.Begin(false)
+	tx, err := rootBolt.Begin(false)
 	if err != nil {
 		return nil, fmt.Errorf("RollbackPoints: failed to start" +
 			" read-only transaction")
@@ -49,6 +59,7 @@ func (s *Scorch) RollbackPoints() ([]*RollbackPoint, error) {
 	// read-only bolt transactions to be rolled back
 	defer func() {
 		_ = tx.Rollback()
+		_ = rootBolt.Close()
 	}()
 
 	snapshots := tx.Bucket(boltSnapshotsBucket)
@@ -105,69 +116,98 @@ func (s *Scorch) RollbackPoints() ([]*RollbackPoint, error) {
 	return rollbackPoints, nil
 }
 
-// Rollback atomically and durably (if unsafeBatch is unset) brings
-// the store back to the point in time as represented by the
-// RollbackPoint. Rollback() should only be passed a RollbackPoint
-// that came from the same store using the RollbackPoints() API.
-func (s *Scorch) Rollback(to *RollbackPoint) error {
+// Rollback atomically and durably brings the store back to the point
+// in time as represented by the RollbackPoint.
+// Rollback() should only be passed a RollbackPoint that came from the
+// same store using the RollbackPoints() API along with the index path.
+func Rollback(path string, to *RollbackPoint) error {
 	if to == nil {
 		return fmt.Errorf("Rollback: RollbackPoint is nil")
 	}
-
-	if s.rootBolt == nil {
-		return fmt.Errorf("Rollback: root is nil")
+	if len(path) == 0 {
+		return fmt.Errorf("Rollback: index path is empty")
 	}
 
-	revert := &snapshotReversion{}
-
-	s.rootLock.Lock()
+	rootBoltPath := path + string(os.PathSeparator) + "root.bolt"
+	rootBoltOpt := &bolt.Options{
+		ReadOnly: false,
+	}
+	rootBolt, err := bolt.Open(rootBoltPath, 0600, rootBoltOpt)
+	if err != nil || rootBolt == nil {
+		return err
+	}
+	defer func() {
+		err1 := rootBolt.Close()
+		if err1 != nil && err == nil {
+			err = err1
+		}
+	}()
 
-	err := s.rootBolt.View(func(tx *bolt.Tx) error {
+	// pick all the younger persisted epochs in bolt store
+	// including the target one.
+	var found bool
+	var eligibleEpochs []uint64
+	err = rootBolt.View(func(tx *bolt.Tx) error {
 		snapshots := tx.Bucket(boltSnapshotsBucket)
 		if snapshots == nil {
-			return fmt.Errorf("Rollback: no snapshots available")
-		}
-
-		pos := segment.EncodeUvarintAscending(nil, to.epoch)
-
-		snapshot := snapshots.Bucket(pos)
-		if snapshot == nil {
-			return fmt.Errorf("Rollback: snapshot not found")
+			return nil
 		}
-
-		indexSnapshot, err := s.loadSnapshot(snapshot)
-		if err != nil {
-			return fmt.Errorf("Rollback: unable to load snapshot: %v", err)
-		}
-
-		// add segments referenced by loaded index snapshot to the
-		// ineligibleForRemoval map
-		for _, segSnap := range indexSnapshot.segment {
-			filename := zapFileName(segSnap.id)
-			s.ineligibleForRemoval[filename] = true
+		sc := snapshots.Cursor()
+		for sk, _ := sc.Last(); sk != nil && !found; sk, _ = sc.Prev() {
+			_, snapshotEpoch, err := segment.DecodeUvarintAscending(sk)
+			if err != nil {
+				continue
+			}
+			if snapshotEpoch == to.epoch {
+				found = true
+			}
+			eligibleEpochs = append(eligibleEpochs, snapshotEpoch)
 		}
-
-		revert.snapshot = indexSnapshot
-		revert.applied = make(chan error)
-		revert.persisted = make(chan error)
-
 		return nil
 	})
 
-	s.rootLock.Unlock()
+	if len(eligibleEpochs) == 0 {
+		return fmt.Errorf("Rollback: no persisted epochs found in bolt")
+	}
+	if !found {
+		return fmt.Errorf("Rollback: target epoch %d not found in bolt", to.epoch)
+	}
 
+	// start a write transaction
+	tx, err := rootBolt.Begin(true)
 	if err != nil {
 		return err
 	}
 
-	// introduce the reversion
-	s.revertToSnapshots <- revert
+	defer func() {
+		if err == nil {
+			err = tx.Commit()
+		} else {
+			_ = tx.Rollback()
+		}
+		if err == nil {
+			err = rootBolt.Sync()
+		}
+	}()
 
-	// block until this snapshot is applied
-	err = <-revert.applied
-	if err != nil {
-		return fmt.Errorf("Rollback: failed with err: %v", err)
+	snapshots := tx.Bucket(boltSnapshotsBucket)
+	if snapshots == nil {
+		return nil
+	}
+	for _, epoch := range eligibleEpochs {
+		k := segment.EncodeUvarintAscending(nil, epoch)
+		if err != nil {
+			continue
+		}
+		if epoch == to.epoch {
+			// return here as it already processed until the given epoch
+			return nil
+		}
+		err = snapshots.DeleteBucket(k)
+		if err == bolt.ErrBucketNotFound {
+			err = nil
+		}
 	}
 
-	return <-revert.persisted
+	return err
 }
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/stats.go b/vendor/github.com/blevesearch/bleve/index/scorch/stats.go
index 6549fddf51..e638362a71 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/stats.go
+++ b/vendor/github.com/blevesearch/bleve/index/scorch/stats.go
@@ -98,10 +98,12 @@ type Stats struct {
 	TotFileSegmentsAtRoot     uint64
 	TotFileMergeWrittenBytes  uint64
 
-	TotFileMergeZapBeg  uint64
-	TotFileMergeZapEnd  uint64
-	TotFileMergeZapTime uint64
-	MaxFileMergeZapTime uint64
+	TotFileMergeZapBeg              uint64
+	TotFileMergeZapEnd              uint64
+	TotFileMergeZapTime             uint64
+	MaxFileMergeZapTime             uint64
+	TotFileMergeZapIntroductionTime uint64
+	MaxFileMergeZapIntroductionTime uint64
 
 	TotFileMergeIntroductions        uint64
 	TotFileMergeIntroductionsDone    uint64
diff --git a/vendor/github.com/blevesearch/bleve/index/store/boltdb/iterator.go b/vendor/github.com/blevesearch/bleve/index/store/boltdb/iterator.go
index 4b5019f1f2..cf4da87c35 100644
--- a/vendor/github.com/blevesearch/bleve/index/store/boltdb/iterator.go
+++ b/vendor/github.com/blevesearch/bleve/index/store/boltdb/iterator.go
@@ -17,7 +17,7 @@ package boltdb
 import (
 	"bytes"
 
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 type Iterator struct {
diff --git a/vendor/github.com/blevesearch/bleve/index/store/boltdb/reader.go b/vendor/github.com/blevesearch/bleve/index/store/boltdb/reader.go
index 4cd94183c6..7977ebbe56 100644
--- a/vendor/github.com/blevesearch/bleve/index/store/boltdb/reader.go
+++ b/vendor/github.com/blevesearch/bleve/index/store/boltdb/reader.go
@@ -16,7 +16,7 @@ package boltdb
 
 import (
 	"github.com/blevesearch/bleve/index/store"
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 type Reader struct {
diff --git a/vendor/github.com/blevesearch/bleve/index/store/boltdb/store.go b/vendor/github.com/blevesearch/bleve/index/store/boltdb/store.go
index 56613d5315..3c749693c0 100644
--- a/vendor/github.com/blevesearch/bleve/index/store/boltdb/store.go
+++ b/vendor/github.com/blevesearch/bleve/index/store/boltdb/store.go
@@ -30,7 +30,7 @@ import (
 
 	"github.com/blevesearch/bleve/index/store"
 	"github.com/blevesearch/bleve/registry"
-	bolt "github.com/etcd-io/bbolt"
+	bolt "go.etcd.io/bbolt"
 )
 
 const (
diff --git a/vendor/github.com/blevesearch/bleve/index/upsidedown/upsidedown.go b/vendor/github.com/blevesearch/bleve/index/upsidedown/upsidedown.go
index 24f5aae949..8e915c6ad5 100644
--- a/vendor/github.com/blevesearch/bleve/index/upsidedown/upsidedown.go
+++ b/vendor/github.com/blevesearch/bleve/index/upsidedown/upsidedown.go
@@ -820,7 +820,8 @@ func (udc *UpsideDownCouch) Batch(batch *index.Batch) (err error) {
 
 	if numUpdates > 0 {
 		go func() {
-			for _, doc := range batch.IndexOps {
+			for k := range batch.IndexOps {
+				doc := batch.IndexOps[k]
 				if doc != nil {
 					aw := index.NewAnalysisWork(udc, doc, resultChan)
 					// put the work on the queue
diff --git a/vendor/github.com/blevesearch/bleve/search/collector/topn.go b/vendor/github.com/blevesearch/bleve/search/collector/topn.go
index a027a12c22..8d4afb63a0 100644
--- a/vendor/github.com/blevesearch/bleve/search/collector/topn.go
+++ b/vendor/github.com/blevesearch/bleve/search/collector/topn.go
@@ -17,6 +17,7 @@ package collector
 import (
 	"context"
 	"reflect"
+	"strconv"
 	"time"
 
 	"github.com/blevesearch/bleve/index"
@@ -90,6 +91,18 @@ func NewTopNCollectorAfter(size int, sort search.SortOrder, after []string) *Top
 	rv.searchAfter = &search.DocumentMatch{
 		Sort: after,
 	}
+
+	for pos, ss := range sort {
+		if ss.RequiresDocID() {
+			rv.searchAfter.ID = after[pos]
+		}
+		if ss.RequiresScoring() {
+			if score, err := strconv.ParseFloat(after[pos], 64); err == nil {
+				rv.searchAfter.Score = score
+			}
+		}
+	}
+
 	return rv
 }
 
diff --git a/vendor/github.com/blevesearch/bleve/search/highlight/fragmenter/simple/simple.go b/vendor/github.com/blevesearch/bleve/search/highlight/fragmenter/simple/simple.go
index 6f6ecedf55..9c63f7fb6c 100644
--- a/vendor/github.com/blevesearch/bleve/search/highlight/fragmenter/simple/simple.go
+++ b/vendor/github.com/blevesearch/bleve/search/highlight/fragmenter/simple/simple.go
@@ -58,6 +58,11 @@ OUTER:
 		// push back towards beginning
 		// without cross maxbegin
 		for start > 0 && used < s.fragmentSize {
+			if start > len(orig) {
+				// bail if out of bounds, possibly due to token replacement
+				// e.g with a regexp replacement
+				continue OUTER
+			}
 			r, size := utf8.DecodeLastRune(orig[0:start])
 			if r == utf8.RuneError {
 				continue OUTER // bail
diff --git a/vendor/github.com/blevesearch/bleve/search/searcher/search_geoboundingbox.go b/vendor/github.com/blevesearch/bleve/search/searcher/search_geoboundingbox.go
index 38cb6467fb..c4b8af9270 100644
--- a/vendor/github.com/blevesearch/bleve/search/searcher/search_geoboundingbox.go
+++ b/vendor/github.com/blevesearch/bleve/search/searcher/search_geoboundingbox.go
@@ -224,7 +224,8 @@ func ComputeGeoRange(term uint64, shift uint,
 func buildRectFilter(dvReader index.DocValueReader, field string,
 	minLon, minLat, maxLon, maxLat float64) FilterFunc {
 	return func(d *search.DocumentMatch) bool {
-		var lon, lat float64
+		// check geo matches against all numeric type terms indexed
+		var lons, lats []float64
 		var found bool
 		err := dvReader.VisitDocValues(d.IndexInternalID, func(field string, term []byte) {
 			// only consider the values which are shifted 0
@@ -234,15 +235,19 @@ func buildRectFilter(dvReader index.DocValueReader, field string,
 				var i64 int64
 				i64, err = prefixCoded.Int64()
 				if err == nil {
-					lon = geo.MortonUnhashLon(uint64(i64))
-					lat = geo.MortonUnhashLat(uint64(i64))
+					lons = append(lons, geo.MortonUnhashLon(uint64(i64)))
+					lats = append(lats, geo.MortonUnhashLat(uint64(i64)))
 					found = true
 				}
 			}
 		})
 		if err == nil && found {
-			return geo.BoundingBoxContains(lon, lat,
-				minLon, minLat, maxLon, maxLat)
+			for i := range lons {
+				if geo.BoundingBoxContains(lons[i], lats[i],
+					minLon, minLat, maxLon, maxLat) {
+					return true
+				}
+			}
 		}
 		return false
 	}
diff --git a/vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go b/vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go
index b01ae6a0af..b6f2932445 100644
--- a/vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go
+++ b/vendor/github.com/blevesearch/bleve/search/searcher/search_geopointdistance.go
@@ -83,7 +83,7 @@ func boxSearcher(indexReader index.IndexReader,
 		return boxSearcher, nil
 	}
 
-	// build geoboundinggox searcher for that bounding box
+	// build geoboundingbox searcher for that bounding box
 	boxSearcher, err := NewGeoBoundingBoxSearcher(indexReader,
 		topLeftLon, bottomRightLat, bottomRightLon, topLeftLat, field, boost,
 		options, checkBoundaries)
@@ -96,7 +96,8 @@ func boxSearcher(indexReader index.IndexReader,
 func buildDistFilter(dvReader index.DocValueReader, field string,
 	centerLon, centerLat, maxDist float64) FilterFunc {
 	return func(d *search.DocumentMatch) bool {
-		var lon, lat float64
+		// check geo matches against all numeric type terms indexed
+		var lons, lats []float64
 		var found bool
 
 		err := dvReader.VisitDocValues(d.IndexInternalID, func(field string, term []byte) {
@@ -106,16 +107,18 @@ func buildDistFilter(dvReader index.DocValueReader, field string,
 			if err == nil && shift == 0 {
 				i64, err := prefixCoded.Int64()
 				if err == nil {
-					lon = geo.MortonUnhashLon(uint64(i64))
-					lat = geo.MortonUnhashLat(uint64(i64))
+					lons = append(lons, geo.MortonUnhashLon(uint64(i64)))
+					lats = append(lats, geo.MortonUnhashLat(uint64(i64)))
 					found = true
 				}
 			}
 		})
 		if err == nil && found {
-			dist := geo.Haversin(lon, lat, centerLon, centerLat)
-			if dist <= maxDist/1000 {
-				return true
+			for i := range lons {
+				dist := geo.Haversin(lons[i], lats[i], centerLon, centerLat)
+				if dist <= maxDist/1000 {
+					return true
+				}
 			}
 		}
 		return false
diff --git a/vendor/github.com/blevesearch/bleve/search/searcher/search_geopolygon.go b/vendor/github.com/blevesearch/bleve/search/searcher/search_geopolygon.go
index 3bb47519d0..5f16aa8d26 100644
--- a/vendor/github.com/blevesearch/bleve/search/searcher/search_geopolygon.go
+++ b/vendor/github.com/blevesearch/bleve/search/searcher/search_geopolygon.go
@@ -15,6 +15,7 @@
 package searcher
 
 import (
+	"fmt"
 	"github.com/blevesearch/bleve/geo"
 	"github.com/blevesearch/bleve/index"
 	"github.com/blevesearch/bleve/numeric"
@@ -26,6 +27,10 @@ func NewGeoBoundedPolygonSearcher(indexReader index.IndexReader,
 	polygon []geo.Point, field string, boost float64,
 	options search.SearcherOptions) (search.Searcher, error) {
 
+	if len(polygon) < 3 {
+		return nil, fmt.Errorf("Too few points specified for the polygon boundary")
+	}
+
 	// compute the bounding box enclosing the polygon
 	topLeftLon, topLeftLat, bottomRightLon, bottomRightLat, err :=
 		geo.BoundingRectangleForPolygon(polygon)
@@ -63,7 +68,8 @@ func almostEqual(a, b float64) bool {
 func buildPolygonFilter(dvReader index.DocValueReader, field string,
 	polygon []geo.Point) FilterFunc {
 	return func(d *search.DocumentMatch) bool {
-		var lon, lat float64
+		// check geo matches against all numeric type terms indexed
+		var lons, lats []float64
 		var found bool
 
 		err := dvReader.VisitDocValues(d.IndexInternalID, func(field string, term []byte) {
@@ -73,8 +79,8 @@ func buildPolygonFilter(dvReader index.DocValueReader, field string,
 			if err == nil && shift == 0 {
 				i64, err := prefixCoded.Int64()
 				if err == nil {
-					lon = geo.MortonUnhashLon(uint64(i64))
-					lat = geo.MortonUnhashLat(uint64(i64))
+					lons = append(lons, geo.MortonUnhashLon(uint64(i64)))
+					lats = append(lats, geo.MortonUnhashLat(uint64(i64)))
 					found = true
 				}
 			}
@@ -84,26 +90,36 @@ func buildPolygonFilter(dvReader index.DocValueReader, field string,
 		// the polygon. ie it might fail for certain points on the polygon boundaries.
 		if err == nil && found {
 			nVertices := len(polygon)
-			var inside bool
-			// check for a direct vertex match
-			if almostEqual(polygon[0].Lat, lat) &&
-				almostEqual(polygon[0].Lon, lon) {
-				return true
+			if len(polygon) < 3 {
+				return false
+			}
+			rayIntersectsSegment := func(point, a, b geo.Point) bool {
+				return (a.Lat > point.Lat) != (b.Lat > point.Lat) &&
+					point.Lon < (b.Lon-a.Lon)*(point.Lat-a.Lat)/(b.Lat-a.Lat)+a.Lon
 			}
 
-			for i := 1; i < nVertices; i++ {
-				if almostEqual(polygon[i].Lat, lat) &&
-					almostEqual(polygon[i].Lon, lon) {
+			for i := range lons {
+				pt := geo.Point{Lon: lons[i], Lat: lats[i]}
+				inside := rayIntersectsSegment(pt, polygon[len(polygon)-1], polygon[0])
+				// check for a direct vertex match
+				if almostEqual(polygon[0].Lat, lats[i]) &&
+					almostEqual(polygon[0].Lon, lons[i]) {
 					return true
 				}
-				if (polygon[i].Lat > lat) != (polygon[i-1].Lat > lat) &&
-					lon < (polygon[i-1].Lon-polygon[i].Lon)*(lat-polygon[i].Lat)/
-						(polygon[i-1].Lat-polygon[i].Lat)+polygon[i].Lon {
-					inside = !inside
+
+				for j := 1; j < nVertices; j++ {
+					if almostEqual(polygon[j].Lat, lats[i]) &&
+						almostEqual(polygon[j].Lon, lons[i]) {
+						return true
+					}
+					if rayIntersectsSegment(pt, polygon[j-1], polygon[j]) {
+						inside = !inside
+					}
+				}
+				if inside {
+					return true
 				}
 			}
-			return inside
-
 		}
 		return false
 	}
diff --git a/vendor/github.com/blevesearch/go-porterstemmer/go.mod b/vendor/github.com/blevesearch/go-porterstemmer/go.mod
new file mode 100644
index 0000000000..d620295d5d
--- /dev/null
+++ b/vendor/github.com/blevesearch/go-porterstemmer/go.mod
@@ -0,0 +1,3 @@
+module github.com/blevesearch/go-porterstemmer
+
+go 1.13
diff --git a/vendor/github.com/edsrzf/mmap-go/.gitignore b/vendor/github.com/blevesearch/mmap-go/.gitignore
index 9aa02c1ed3..0c0a5e4916 100644
--- a/vendor/github.com/edsrzf/mmap-go/.gitignore
+++ b/vendor/github.com/blevesearch/mmap-go/.gitignore
@@ -6,3 +6,5 @@
 _obj
 _test
 testdata
+/.idea
+*.iml
\ No newline at end of file
diff --git a/vendor/github.com/blevesearch/mmap-go/.travis.yml b/vendor/github.com/blevesearch/mmap-go/.travis.yml
new file mode 100644
index 0000000000..169eb1f354
--- /dev/null
+++ b/vendor/github.com/blevesearch/mmap-go/.travis.yml
@@ -0,0 +1,16 @@
+language: go
+os:
+  - linux
+  - osx
+  - windows
+go:
+  - 1.11.4
+env:
+  global:
+    - GO111MODULE=on
+install:
+  - go mod download
+  - go get github.com/mattn/goveralls
+script:
+  - go test -v -covermode=count -coverprofile=coverage.out -bench . -cpu 1,4
+  - '[ "${TRAVIS_PULL_REQUEST}" = "false" ] && $HOME/gopath/bin/goveralls -coverprofile=coverage.out -service=travis-ci -repotoken $COVERALLS_TOKEN || true'
diff --git a/vendor/github.com/edsrzf/mmap-go/LICENSE b/vendor/github.com/blevesearch/mmap-go/LICENSE
index 8f05f338ac..8f05f338ac 100644
--- a/vendor/github.com/edsrzf/mmap-go/LICENSE
+++ b/vendor/github.com/blevesearch/mmap-go/LICENSE
diff --git a/vendor/github.com/edsrzf/mmap-go/README.md b/vendor/github.com/blevesearch/mmap-go/README.md
index 4cc2bfe1c8..4cc2bfe1c8 100644
--- a/vendor/github.com/edsrzf/mmap-go/README.md
+++ b/vendor/github.com/blevesearch/mmap-go/README.md
diff --git a/vendor/github.com/blevesearch/mmap-go/go.mod b/vendor/github.com/blevesearch/mmap-go/go.mod
new file mode 100644
index 0000000000..b7f0265734
--- /dev/null
+++ b/vendor/github.com/blevesearch/mmap-go/go.mod
@@ -0,0 +1,3 @@
+module github.com/blevesearch/mmap-go
+
+require golang.org/x/sys v0.0.0-20181221143128-b4a75ba826a6
diff --git a/vendor/github.com/blevesearch/mmap-go/go.sum b/vendor/github.com/blevesearch/mmap-go/go.sum
new file mode 100644
index 0000000000..db2bff5e0f
--- /dev/null
+++ b/vendor/github.com/blevesearch/mmap-go/go.sum
@@ -0,0 +1,2 @@
+golang.org/x/sys v0.0.0-20181221143128-b4a75ba826a6 h1:IcgEB62HYgAhX0Nd/QrVgZlxlcyxbGQHElLUhW2X4Fo=
+golang.org/x/sys v0.0.0-20181221143128-b4a75ba826a6/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
diff --git a/vendor/github.com/edsrzf/mmap-go/mmap.go b/vendor/github.com/blevesearch/mmap-go/mmap.go
index 29655bd222..29655bd222 100644
--- a/vendor/github.com/edsrzf/mmap-go/mmap.go
+++ b/vendor/github.com/blevesearch/mmap-go/mmap.go
diff --git a/vendor/github.com/edsrzf/mmap-go/mmap_unix.go b/vendor/github.com/blevesearch/mmap-go/mmap_unix.go
index 25b13e51fd..25b13e51fd 100644
--- a/vendor/github.com/edsrzf/mmap-go/mmap_unix.go
+++ b/vendor/github.com/blevesearch/mmap-go/mmap_unix.go
diff --git a/vendor/github.com/edsrzf/mmap-go/mmap_windows.go b/vendor/github.com/blevesearch/mmap-go/mmap_windows.go
index 7910da2577..631b3825f9 100644
--- a/vendor/github.com/edsrzf/mmap-go/mmap_windows.go
+++ b/vendor/github.com/blevesearch/mmap-go/mmap_windows.go
@@ -22,8 +22,9 @@ import (
 // We keep this map so that we can get back the original handle from the memory address.
 
 type addrinfo struct {
-	file    windows.Handle
-	mapview windows.Handle
+	file     windows.Handle
+	mapview  windows.Handle
+	writable bool
 }
 
 var handleLock sync.Mutex
@@ -32,13 +33,16 @@ var handleMap = map[uintptr]*addrinfo{}
 func mmap(len int, prot, flags, hfile uintptr, off int64) ([]byte, error) {
 	flProtect := uint32(windows.PAGE_READONLY)
 	dwDesiredAccess := uint32(windows.FILE_MAP_READ)
+	writable := false
 	switch {
 	case prot&COPY != 0:
 		flProtect = windows.PAGE_WRITECOPY
 		dwDesiredAccess = windows.FILE_MAP_COPY
+		writable = true
 	case prot&RDWR != 0:
 		flProtect = windows.PAGE_READWRITE
 		dwDesiredAccess = windows.FILE_MAP_WRITE
+		writable = true
 	}
 	if prot&EXEC != 0 {
 		flProtect <<= 4
@@ -67,8 +71,9 @@ func mmap(len int, prot, flags, hfile uintptr, off int64) ([]byte, error) {
 	}
 	handleLock.Lock()
 	handleMap[addr] = &addrinfo{
-		file:    windows.Handle(hfile),
-		mapview: h,
+		file:     windows.Handle(hfile),
+		mapview:  h,
+		writable: writable,
 	}
 	handleLock.Unlock()
 
@@ -96,8 +101,13 @@ func (m MMap) flush() error {
 		return errors.New("unknown base address")
 	}
 
-	errno = windows.FlushFileBuffers(handle.file)
-	return os.NewSyscallError("FlushFileBuffers", errno)
+	if handle.writable {
+		if err := windows.FlushFileBuffers(handle.file); err != nil {
+			return os.NewSyscallError("FlushFileBuffers", err)
+		}
+	}
+
+	return nil
 }
 
 func (m MMap) lock() error {
diff --git a/vendor/github.com/blevesearch/segment/go.mod b/vendor/github.com/blevesearch/segment/go.mod
new file mode 100644
index 0000000000..2f65976564
--- /dev/null
+++ b/vendor/github.com/blevesearch/segment/go.mod
@@ -0,0 +1,3 @@
+module github.com/blevesearch/segment
+
+go 1.13
diff --git a/vendor/github.com/blevesearch/snowballstem/COPYING b/vendor/github.com/blevesearch/snowballstem/COPYING
new file mode 100644
index 0000000000..f36607f9e9
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/COPYING
@@ -0,0 +1,29 @@
+Copyright (c) 2001, Dr Martin Porter
+Copyright (c) 2004,2005, Richard Boulton
+Copyright (c) 2013, Yoshiki Shibukawa
+Copyright (c) 2006,2007,2009,2010,2011,2014-2019, Olly Betts
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+  1. Redistributions of source code must retain the above copyright notice,
+     this list of conditions and the following disclaimer.
+  2. Redistributions in binary form must reproduce the above copyright notice,
+     this list of conditions and the following disclaimer in the documentation
+     and/or other materials provided with the distribution.
+  3. Neither the name of the Snowball project nor the names of its contributors
+     may be used to endorse or promote products derived from this software
+     without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/blevesearch/snowballstem/README.md b/vendor/github.com/blevesearch/snowballstem/README.md
new file mode 100644
index 0000000000..bb4ff8ab96
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/README.md
@@ -0,0 +1,66 @@
+# snowballstem
+
+This repository contains the Go stemmers generated by the [Snowball](https://github.com/snowballstem/snowball) project.  They are maintained outside of the core bleve package so that they may be more easily be reused in other contexts.
+
+## Usage
+
+All these stemmers export a single `Stem()` method which operates on a snowball `Env` structure.  The `Env` structure maintains all state for the stemmer.  A new `Env` is created to point at an initial string.  After stemming, the results of the `Stem()` operation can be retrieved using the `Current()` method.  The `Env` structure can be reused for subsequent calls by using the `SetCurrent()` method.
+
+## Example
+
+```
+package main
+
+import (
+	"fmt"
+
+	"github.com/blevesearch/snowballstem"
+	"github.com/blevesearch/snowballstem/english"
+)
+
+func main() {
+
+	// words to stem
+	words := []string{
+		"running",
+		"jumping",
+	}
+
+	// build new environment
+	env := snowballstem.NewEnv("")
+
+	for _, word := range words {
+		// set up environment for word
+		env.SetCurrent(word)
+		// invoke stemmer
+		english.Stem(env)
+		// print results
+		fmt.Printf("%s stemmed to %s\n", word, env.Current())
+	}
+}
+```
+Produces Output:
+```
+$ ./snowtest
+running stemmed to run
+jumping stemmed to jump
+```
+
+## Testing
+
+The test harness for these stemmers is hosted in the main [Snowball](https://github.com/snowballstem/snowball) repository.  There are functional tests built around the separate [snowballstem-data](https://github.com/snowballstem/snowball-data) repository, and there is support for fuzz-testing the stemmers there as well.
+
+## Generating the Stemmers
+
+```
+$ export SNOWBALL=/path/to/github.com/snowballstem/snowball/after/snowball/built
+$ go generate
+```
+
+## Updated the Go Generate Commands
+
+A simple tool is provided to automate these from the snowball algorithms directory:
+
+```
+$ go run gengen.go /path/to/github.com/snowballstem/snowball/algorithms
+```
diff --git a/vendor/github.com/blevesearch/snowballstem/among.go b/vendor/github.com/blevesearch/snowballstem/among.go
new file mode 100644
index 0000000000..1a0c70257f
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/among.go
@@ -0,0 +1,16 @@
+package snowballstem
+
+import "fmt"
+
+type AmongF func(env *Env, ctx interface{}) bool
+
+type Among struct {
+	Str string
+	A   int32
+	B   int32
+	F   AmongF
+}
+
+func (a *Among) String() string {
+	return fmt.Sprintf("str: `%s`, a: %d, b: %d, f: %p", a.Str, a.A, a.B, a.F)
+}
diff --git a/vendor/github.com/blevesearch/snowballstem/english/english_stemmer.go b/vendor/github.com/blevesearch/snowballstem/english/english_stemmer.go
new file mode 100644
index 0000000000..87e1d48e7d
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/english/english_stemmer.go
@@ -0,0 +1,1341 @@
+//! This file was generated automatically by the Snowball to Go compiler
+//! http://snowballstem.org/
+
+package english
+
+import (
+	snowballRuntime "github.com/blevesearch/snowballstem"
+)
+
+var A_0 = []*snowballRuntime.Among{
+	{Str: "arsen", A: -1, B: -1, F: nil},
+	{Str: "commun", A: -1, B: -1, F: nil},
+	{Str: "gener", A: -1, B: -1, F: nil},
+}
+
+var A_1 = []*snowballRuntime.Among{
+	{Str: "'", A: -1, B: 1, F: nil},
+	{Str: "'s'", A: 0, B: 1, F: nil},
+	{Str: "'s", A: -1, B: 1, F: nil},
+}
+
+var A_2 = []*snowballRuntime.Among{
+	{Str: "ied", A: -1, B: 2, F: nil},
+	{Str: "s", A: -1, B: 3, F: nil},
+	{Str: "ies", A: 1, B: 2, F: nil},
+	{Str: "sses", A: 1, B: 1, F: nil},
+	{Str: "ss", A: 1, B: -1, F: nil},
+	{Str: "us", A: 1, B: -1, F: nil},
+}
+
+var A_3 = []*snowballRuntime.Among{
+	{Str: "", A: -1, B: 3, F: nil},
+	{Str: "bb", A: 0, B: 2, F: nil},
+	{Str: "dd", A: 0, B: 2, F: nil},
+	{Str: "ff", A: 0, B: 2, F: nil},
+	{Str: "gg", A: 0, B: 2, F: nil},
+	{Str: "bl", A: 0, B: 1, F: nil},
+	{Str: "mm", A: 0, B: 2, F: nil},
+	{Str: "nn", A: 0, B: 2, F: nil},
+	{Str: "pp", A: 0, B: 2, F: nil},
+	{Str: "rr", A: 0, B: 2, F: nil},
+	{Str: "at", A: 0, B: 1, F: nil},
+	{Str: "tt", A: 0, B: 2, F: nil},
+	{Str: "iz", A: 0, B: 1, F: nil},
+}
+
+var A_4 = []*snowballRuntime.Among{
+	{Str: "ed", A: -1, B: 2, F: nil},
+	{Str: "eed", A: 0, B: 1, F: nil},
+	{Str: "ing", A: -1, B: 2, F: nil},
+	{Str: "edly", A: -1, B: 2, F: nil},
+	{Str: "eedly", A: 3, B: 1, F: nil},
+	{Str: "ingly", A: -1, B: 2, F: nil},
+}
+
+var A_5 = []*snowballRuntime.Among{
+	{Str: "anci", A: -1, B: 3, F: nil},
+	{Str: "enci", A: -1, B: 2, F: nil},
+	{Str: "ogi", A: -1, B: 13, F: nil},
+	{Str: "li", A: -1, B: 16, F: nil},
+	{Str: "bli", A: 3, B: 12, F: nil},
+	{Str: "abli", A: 4, B: 4, F: nil},
+	{Str: "alli", A: 3, B: 8, F: nil},
+	{Str: "fulli", A: 3, B: 14, F: nil},
+	{Str: "lessli", A: 3, B: 15, F: nil},
+	{Str: "ousli", A: 3, B: 10, F: nil},
+	{Str: "entli", A: 3, B: 5, F: nil},
+	{Str: "aliti", A: -1, B: 8, F: nil},
+	{Str: "biliti", A: -1, B: 12, F: nil},
+	{Str: "iviti", A: -1, B: 11, F: nil},
+	{Str: "tional", A: -1, B: 1, F: nil},
+	{Str: "ational", A: 14, B: 7, F: nil},
+	{Str: "alism", A: -1, B: 8, F: nil},
+	{Str: "ation", A: -1, B: 7, F: nil},
+	{Str: "ization", A: 17, B: 6, F: nil},
+	{Str: "izer", A: -1, B: 6, F: nil},
+	{Str: "ator", A: -1, B: 7, F: nil},
+	{Str: "iveness", A: -1, B: 11, F: nil},
+	{Str: "fulness", A: -1, B: 9, F: nil},
+	{Str: "ousness", A: -1, B: 10, F: nil},
+}
+
+var A_6 = []*snowballRuntime.Among{
+	{Str: "icate", A: -1, B: 4, F: nil},
+	{Str: "ative", A: -1, B: 6, F: nil},
+	{Str: "alize", A: -1, B: 3, F: nil},
+	{Str: "iciti", A: -1, B: 4, F: nil},
+	{Str: "ical", A: -1, B: 4, F: nil},
+	{Str: "tional", A: -1, B: 1, F: nil},
+	{Str: "ational", A: 5, B: 2, F: nil},
+	{Str: "ful", A: -1, B: 5, F: nil},
+	{Str: "ness", A: -1, B: 5, F: nil},
+}
+
+var A_7 = []*snowballRuntime.Among{
+	{Str: "ic", A: -1, B: 1, F: nil},
+	{Str: "ance", A: -1, B: 1, F: nil},
+	{Str: "ence", A: -1, B: 1, F: nil},
+	{Str: "able", A: -1, B: 1, F: nil},
+	{Str: "ible", A: -1, B: 1, F: nil},
+	{Str: "ate", A: -1, B: 1, F: nil},
+	{Str: "ive", A: -1, B: 1, F: nil},
+	{Str: "ize", A: -1, B: 1, F: nil},
+	{Str: "iti", A: -1, B: 1, F: nil},
+	{Str: "al", A: -1, B: 1, F: nil},
+	{Str: "ism", A: -1, B: 1, F: nil},
+	{Str: "ion", A: -1, B: 2, F: nil},
+	{Str: "er", A: -1, B: 1, F: nil},
+	{Str: "ous", A: -1, B: 1, F: nil},
+	{Str: "ant", A: -1, B: 1, F: nil},
+	{Str: "ent", A: -1, B: 1, F: nil},
+	{Str: "ment", A: 15, B: 1, F: nil},
+	{Str: "ement", A: 16, B: 1, F: nil},
+}
+
+var A_8 = []*snowballRuntime.Among{
+	{Str: "e", A: -1, B: 1, F: nil},
+	{Str: "l", A: -1, B: 2, F: nil},
+}
+
+var A_9 = []*snowballRuntime.Among{
+	{Str: "succeed", A: -1, B: -1, F: nil},
+	{Str: "proceed", A: -1, B: -1, F: nil},
+	{Str: "exceed", A: -1, B: -1, F: nil},
+	{Str: "canning", A: -1, B: -1, F: nil},
+	{Str: "inning", A: -1, B: -1, F: nil},
+	{Str: "earring", A: -1, B: -1, F: nil},
+	{Str: "herring", A: -1, B: -1, F: nil},
+	{Str: "outing", A: -1, B: -1, F: nil},
+}
+
+var A_10 = []*snowballRuntime.Among{
+	{Str: "andes", A: -1, B: -1, F: nil},
+	{Str: "atlas", A: -1, B: -1, F: nil},
+	{Str: "bias", A: -1, B: -1, F: nil},
+	{Str: "cosmos", A: -1, B: -1, F: nil},
+	{Str: "dying", A: -1, B: 3, F: nil},
+	{Str: "early", A: -1, B: 9, F: nil},
+	{Str: "gently", A: -1, B: 7, F: nil},
+	{Str: "howe", A: -1, B: -1, F: nil},
+	{Str: "idly", A: -1, B: 6, F: nil},
+	{Str: "lying", A: -1, B: 4, F: nil},
+	{Str: "news", A: -1, B: -1, F: nil},
+	{Str: "only", A: -1, B: 10, F: nil},
+	{Str: "singly", A: -1, B: 11, F: nil},
+	{Str: "skies", A: -1, B: 2, F: nil},
+	{Str: "skis", A: -1, B: 1, F: nil},
+	{Str: "sky", A: -1, B: -1, F: nil},
+	{Str: "tying", A: -1, B: 5, F: nil},
+	{Str: "ugly", A: -1, B: 8, F: nil},
+}
+
+var G_v = []byte{17, 65, 16, 1}
+
+var G_v_WXY = []byte{1, 17, 65, 208, 1}
+
+var G_valid_LI = []byte{55, 141, 2}
+
+type Context struct {
+	b_Y_found bool
+	i_p2      int
+	i_p1      int
+}
+
+func r_prelude(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 25
+	// unset Y_found, line 26
+	context.b_Y_found = false
+	// do, line 27
+	var v_1 = env.Cursor
+lab0:
+	for {
+		// (, line 27
+		// [, line 27
+		env.Bra = env.Cursor
+		// literal, line 27
+		if !env.EqS("'") {
+			break lab0
+		}
+		// ], line 27
+		env.Ket = env.Cursor
+		// delete, line 27
+		if !env.SliceDel() {
+			return false
+		}
+		break lab0
+	}
+	env.Cursor = v_1
+	// do, line 28
+	var v_2 = env.Cursor
+lab1:
+	for {
+		// (, line 28
+		// [, line 28
+		env.Bra = env.Cursor
+		// literal, line 28
+		if !env.EqS("y") {
+			break lab1
+		}
+		// ], line 28
+		env.Ket = env.Cursor
+		// <-, line 28
+		if !env.SliceFrom("Y") {
+			return false
+		}
+		// set Y_found, line 28
+		context.b_Y_found = true
+		break lab1
+	}
+	env.Cursor = v_2
+	// do, line 29
+	var v_3 = env.Cursor
+lab2:
+	for {
+		// repeat, line 29
+	replab3:
+		for {
+			var v_4 = env.Cursor
+		lab4:
+			for range [2]struct{}{} {
+				// (, line 29
+				// goto, line 29
+			golab5:
+				for {
+					var v_5 = env.Cursor
+				lab6:
+					for {
+						// (, line 29
+						if !env.InGrouping(G_v, 97, 121) {
+							break lab6
+						}
+						// [, line 29
+						env.Bra = env.Cursor
+						// literal, line 29
+						if !env.EqS("y") {
+							break lab6
+						}
+						// ], line 29
+						env.Ket = env.Cursor
+						env.Cursor = v_5
+						break golab5
+					}
+					env.Cursor = v_5
+					if env.Cursor >= env.Limit {
+						break lab4
+					}
+					env.NextChar()
+				}
+				// <-, line 29
+				if !env.SliceFrom("Y") {
+					return false
+				}
+				// set Y_found, line 29
+				context.b_Y_found = true
+				continue replab3
+			}
+			env.Cursor = v_4
+			break replab3
+		}
+		break lab2
+	}
+	env.Cursor = v_3
+	return true
+}
+
+func r_mark_regions(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 32
+	context.i_p1 = env.Limit
+	context.i_p2 = env.Limit
+	// do, line 35
+	var v_1 = env.Cursor
+lab0:
+	for {
+		// (, line 35
+		// or, line 41
+	lab1:
+		for {
+			var v_2 = env.Cursor
+		lab2:
+			for {
+				// among, line 36
+				if env.FindAmong(A_0, context) == 0 {
+					break lab2
+				}
+				break lab1
+			}
+			env.Cursor = v_2
+			// (, line 41
+			// gopast, line 41
+		golab3:
+			for {
+			lab4:
+				for {
+					if !env.InGrouping(G_v, 97, 121) {
+						break lab4
+					}
+					break golab3
+				}
+				if env.Cursor >= env.Limit {
+					break lab0
+				}
+				env.NextChar()
+			}
+			// gopast, line 41
+		golab5:
+			for {
+			lab6:
+				for {
+					if !env.OutGrouping(G_v, 97, 121) {
+						break lab6
+					}
+					break golab5
+				}
+				if env.Cursor >= env.Limit {
+					break lab0
+				}
+				env.NextChar()
+			}
+			break lab1
+		}
+		// setmark p1, line 42
+		context.i_p1 = env.Cursor
+		// gopast, line 43
+	golab7:
+		for {
+		lab8:
+			for {
+				if !env.InGrouping(G_v, 97, 121) {
+					break lab8
+				}
+				break golab7
+			}
+			if env.Cursor >= env.Limit {
+				break lab0
+			}
+			env.NextChar()
+		}
+		// gopast, line 43
+	golab9:
+		for {
+		lab10:
+			for {
+				if !env.OutGrouping(G_v, 97, 121) {
+					break lab10
+				}
+				break golab9
+			}
+			if env.Cursor >= env.Limit {
+				break lab0
+			}
+			env.NextChar()
+		}
+		// setmark p2, line 43
+		context.i_p2 = env.Cursor
+		break lab0
+	}
+	env.Cursor = v_1
+	return true
+}
+
+func r_shortv(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 49
+	// or, line 51
+lab0:
+	for {
+		var v_1 = env.Limit - env.Cursor
+	lab1:
+		for {
+			// (, line 50
+			if !env.OutGroupingB(G_v_WXY, 89, 121) {
+				break lab1
+			}
+			if !env.InGroupingB(G_v, 97, 121) {
+				break lab1
+			}
+			if !env.OutGroupingB(G_v, 97, 121) {
+				break lab1
+			}
+			break lab0
+		}
+		env.Cursor = env.Limit - v_1
+		// (, line 52
+		if !env.OutGroupingB(G_v, 97, 121) {
+			return false
+		}
+		if !env.InGroupingB(G_v, 97, 121) {
+			return false
+		}
+		// atlimit, line 52
+		if env.Cursor > env.LimitBackward {
+			return false
+		}
+		break lab0
+	}
+	return true
+}
+
+func r_R1(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	if !(context.i_p1 <= env.Cursor) {
+		return false
+	}
+	return true
+}
+
+func r_R2(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	if !(context.i_p2 <= env.Cursor) {
+		return false
+	}
+	return true
+}
+
+func r_Step_1a(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 58
+	// try, line 59
+	var v_1 = env.Limit - env.Cursor
+lab0:
+	for {
+		// (, line 59
+		// [, line 60
+		env.Ket = env.Cursor
+		// substring, line 60
+		among_var = env.FindAmongB(A_1, context)
+		if among_var == 0 {
+			env.Cursor = env.Limit - v_1
+			break lab0
+		}
+		// ], line 60
+		env.Bra = env.Cursor
+		if among_var == 0 {
+			env.Cursor = env.Limit - v_1
+			break lab0
+		} else if among_var == 1 {
+			// (, line 62
+			// delete, line 62
+			if !env.SliceDel() {
+				return false
+			}
+		}
+		break lab0
+	}
+	// [, line 65
+	env.Ket = env.Cursor
+	// substring, line 65
+	among_var = env.FindAmongB(A_2, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 65
+	env.Bra = env.Cursor
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 66
+		// <-, line 66
+		if !env.SliceFrom("ss") {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 68
+		// or, line 68
+	lab1:
+		for {
+			var v_2 = env.Limit - env.Cursor
+		lab2:
+			for {
+				// (, line 68
+				{
+					// hop, line 68
+					var c = env.ByteIndexForHop(-(2))
+					if int32(env.LimitBackward) > c || c > int32(env.Limit) {
+						break lab2
+					}
+					env.Cursor = int(c)
+				}
+				// <-, line 68
+				if !env.SliceFrom("i") {
+					return false
+				}
+				break lab1
+			}
+			env.Cursor = env.Limit - v_2
+			// <-, line 68
+			if !env.SliceFrom("ie") {
+				return false
+			}
+			break lab1
+		}
+	} else if among_var == 3 {
+		// (, line 69
+		// next, line 69
+		if env.Cursor <= env.LimitBackward {
+			return false
+		}
+		env.PrevChar()
+		// gopast, line 69
+	golab3:
+		for {
+		lab4:
+			for {
+				if !env.InGroupingB(G_v, 97, 121) {
+					break lab4
+				}
+				break golab3
+			}
+			if env.Cursor <= env.LimitBackward {
+				return false
+			}
+			env.PrevChar()
+		}
+		// delete, line 69
+		if !env.SliceDel() {
+			return false
+		}
+	}
+	return true
+}
+
+func r_Step_1b(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 74
+	// [, line 75
+	env.Ket = env.Cursor
+	// substring, line 75
+	among_var = env.FindAmongB(A_4, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 75
+	env.Bra = env.Cursor
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 77
+		// call R1, line 77
+		if !r_R1(env, context) {
+			return false
+		}
+		// <-, line 77
+		if !env.SliceFrom("ee") {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 79
+		// test, line 80
+		var v_1 = env.Limit - env.Cursor
+		// gopast, line 80
+	golab0:
+		for {
+		lab1:
+			for {
+				if !env.InGroupingB(G_v, 97, 121) {
+					break lab1
+				}
+				break golab0
+			}
+			if env.Cursor <= env.LimitBackward {
+				return false
+			}
+			env.PrevChar()
+		}
+		env.Cursor = env.Limit - v_1
+		// delete, line 80
+		if !env.SliceDel() {
+			return false
+		}
+		// test, line 81
+		var v_3 = env.Limit - env.Cursor
+		// substring, line 81
+		among_var = env.FindAmongB(A_3, context)
+		if among_var == 0 {
+			return false
+		}
+		env.Cursor = env.Limit - v_3
+		if among_var == 0 {
+			return false
+		} else if among_var == 1 {
+			// (, line 83
+			{
+				// <+, line 83
+				var c = env.Cursor
+				bra, ket := env.Cursor, env.Cursor
+				env.Insert(bra, ket, "e")
+				env.Cursor = c
+			}
+		} else if among_var == 2 {
+			// (, line 86
+			// [, line 86
+			env.Ket = env.Cursor
+			// next, line 86
+			if env.Cursor <= env.LimitBackward {
+				return false
+			}
+			env.PrevChar()
+			// ], line 86
+			env.Bra = env.Cursor
+			// delete, line 86
+			if !env.SliceDel() {
+				return false
+			}
+		} else if among_var == 3 {
+			// (, line 87
+			// atmark, line 87
+			if env.Cursor != context.i_p1 {
+				return false
+			}
+			// test, line 87
+			var v_4 = env.Limit - env.Cursor
+			// call shortv, line 87
+			if !r_shortv(env, context) {
+				return false
+			}
+			env.Cursor = env.Limit - v_4
+			{
+				// <+, line 87
+				var c = env.Cursor
+				bra, ket := env.Cursor, env.Cursor
+				env.Insert(bra, ket, "e")
+				env.Cursor = c
+			}
+		}
+	}
+	return true
+}
+
+func r_Step_1c(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 93
+	// [, line 94
+	env.Ket = env.Cursor
+	// or, line 94
+lab0:
+	for {
+		var v_1 = env.Limit - env.Cursor
+	lab1:
+		for {
+			// literal, line 94
+			if !env.EqSB("y") {
+				break lab1
+			}
+			break lab0
+		}
+		env.Cursor = env.Limit - v_1
+		// literal, line 94
+		if !env.EqSB("Y") {
+			return false
+		}
+		break lab0
+	}
+	// ], line 94
+	env.Bra = env.Cursor
+	if !env.OutGroupingB(G_v, 97, 121) {
+		return false
+	}
+	// not, line 95
+	var v_2 = env.Limit - env.Cursor
+lab2:
+	for {
+		// atlimit, line 95
+		if env.Cursor > env.LimitBackward {
+			break lab2
+		}
+		return false
+	}
+	env.Cursor = env.Limit - v_2
+	// <-, line 96
+	if !env.SliceFrom("i") {
+		return false
+	}
+	return true
+}
+
+func r_Step_2(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 99
+	// [, line 100
+	env.Ket = env.Cursor
+	// substring, line 100
+	among_var = env.FindAmongB(A_5, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 100
+	env.Bra = env.Cursor
+	// call R1, line 100
+	if !r_R1(env, context) {
+		return false
+	}
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 101
+		// <-, line 101
+		if !env.SliceFrom("tion") {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 102
+		// <-, line 102
+		if !env.SliceFrom("ence") {
+			return false
+		}
+	} else if among_var == 3 {
+		// (, line 103
+		// <-, line 103
+		if !env.SliceFrom("ance") {
+			return false
+		}
+	} else if among_var == 4 {
+		// (, line 104
+		// <-, line 104
+		if !env.SliceFrom("able") {
+			return false
+		}
+	} else if among_var == 5 {
+		// (, line 105
+		// <-, line 105
+		if !env.SliceFrom("ent") {
+			return false
+		}
+	} else if among_var == 6 {
+		// (, line 107
+		// <-, line 107
+		if !env.SliceFrom("ize") {
+			return false
+		}
+	} else if among_var == 7 {
+		// (, line 109
+		// <-, line 109
+		if !env.SliceFrom("ate") {
+			return false
+		}
+	} else if among_var == 8 {
+		// (, line 111
+		// <-, line 111
+		if !env.SliceFrom("al") {
+			return false
+		}
+	} else if among_var == 9 {
+		// (, line 112
+		// <-, line 112
+		if !env.SliceFrom("ful") {
+			return false
+		}
+	} else if among_var == 10 {
+		// (, line 114
+		// <-, line 114
+		if !env.SliceFrom("ous") {
+			return false
+		}
+	} else if among_var == 11 {
+		// (, line 116
+		// <-, line 116
+		if !env.SliceFrom("ive") {
+			return false
+		}
+	} else if among_var == 12 {
+		// (, line 118
+		// <-, line 118
+		if !env.SliceFrom("ble") {
+			return false
+		}
+	} else if among_var == 13 {
+		// (, line 119
+		// literal, line 119
+		if !env.EqSB("l") {
+			return false
+		}
+		// <-, line 119
+		if !env.SliceFrom("og") {
+			return false
+		}
+	} else if among_var == 14 {
+		// (, line 120
+		// <-, line 120
+		if !env.SliceFrom("ful") {
+			return false
+		}
+	} else if among_var == 15 {
+		// (, line 121
+		// <-, line 121
+		if !env.SliceFrom("less") {
+			return false
+		}
+	} else if among_var == 16 {
+		// (, line 122
+		if !env.InGroupingB(G_valid_LI, 99, 116) {
+			return false
+		}
+		// delete, line 122
+		if !env.SliceDel() {
+			return false
+		}
+	}
+	return true
+}
+
+func r_Step_3(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 126
+	// [, line 127
+	env.Ket = env.Cursor
+	// substring, line 127
+	among_var = env.FindAmongB(A_6, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 127
+	env.Bra = env.Cursor
+	// call R1, line 127
+	if !r_R1(env, context) {
+		return false
+	}
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 128
+		// <-, line 128
+		if !env.SliceFrom("tion") {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 129
+		// <-, line 129
+		if !env.SliceFrom("ate") {
+			return false
+		}
+	} else if among_var == 3 {
+		// (, line 130
+		// <-, line 130
+		if !env.SliceFrom("al") {
+			return false
+		}
+	} else if among_var == 4 {
+		// (, line 132
+		// <-, line 132
+		if !env.SliceFrom("ic") {
+			return false
+		}
+	} else if among_var == 5 {
+		// (, line 134
+		// delete, line 134
+		if !env.SliceDel() {
+			return false
+		}
+	} else if among_var == 6 {
+		// (, line 136
+		// call R2, line 136
+		if !r_R2(env, context) {
+			return false
+		}
+		// delete, line 136
+		if !env.SliceDel() {
+			return false
+		}
+	}
+	return true
+}
+
+func r_Step_4(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 140
+	// [, line 141
+	env.Ket = env.Cursor
+	// substring, line 141
+	among_var = env.FindAmongB(A_7, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 141
+	env.Bra = env.Cursor
+	// call R2, line 141
+	if !r_R2(env, context) {
+		return false
+	}
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 144
+		// delete, line 144
+		if !env.SliceDel() {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 145
+		// or, line 145
+	lab0:
+		for {
+			var v_1 = env.Limit - env.Cursor
+		lab1:
+			for {
+				// literal, line 145
+				if !env.EqSB("s") {
+					break lab1
+				}
+				break lab0
+			}
+			env.Cursor = env.Limit - v_1
+			// literal, line 145
+			if !env.EqSB("t") {
+				return false
+			}
+			break lab0
+		}
+		// delete, line 145
+		if !env.SliceDel() {
+			return false
+		}
+	}
+	return true
+}
+
+func r_Step_5(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 149
+	// [, line 150
+	env.Ket = env.Cursor
+	// substring, line 150
+	among_var = env.FindAmongB(A_8, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 150
+	env.Bra = env.Cursor
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 151
+		// or, line 151
+	lab0:
+		for {
+			var v_1 = env.Limit - env.Cursor
+		lab1:
+			for {
+				// call R2, line 151
+				if !r_R2(env, context) {
+					break lab1
+				}
+				break lab0
+			}
+			env.Cursor = env.Limit - v_1
+			// (, line 151
+			// call R1, line 151
+			if !r_R1(env, context) {
+				return false
+			}
+			// not, line 151
+			var v_2 = env.Limit - env.Cursor
+		lab2:
+			for {
+				// call shortv, line 151
+				if !r_shortv(env, context) {
+					break lab2
+				}
+				return false
+			}
+			env.Cursor = env.Limit - v_2
+			break lab0
+		}
+		// delete, line 151
+		if !env.SliceDel() {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 152
+		// call R2, line 152
+		if !r_R2(env, context) {
+			return false
+		}
+		// literal, line 152
+		if !env.EqSB("l") {
+			return false
+		}
+		// delete, line 152
+		if !env.SliceDel() {
+			return false
+		}
+	}
+	return true
+}
+
+func r_exception2(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 156
+	// [, line 158
+	env.Ket = env.Cursor
+	// substring, line 158
+	if env.FindAmongB(A_9, context) == 0 {
+		return false
+	}
+	// ], line 158
+	env.Bra = env.Cursor
+	// atlimit, line 158
+	if env.Cursor > env.LimitBackward {
+		return false
+	}
+	return true
+}
+
+func r_exception1(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	var among_var int32
+	// (, line 168
+	// [, line 170
+	env.Bra = env.Cursor
+	// substring, line 170
+	among_var = env.FindAmong(A_10, context)
+	if among_var == 0 {
+		return false
+	}
+	// ], line 170
+	env.Ket = env.Cursor
+	// atlimit, line 170
+	if env.Cursor < env.Limit {
+		return false
+	}
+	if among_var == 0 {
+		return false
+	} else if among_var == 1 {
+		// (, line 174
+		// <-, line 174
+		if !env.SliceFrom("ski") {
+			return false
+		}
+	} else if among_var == 2 {
+		// (, line 175
+		// <-, line 175
+		if !env.SliceFrom("sky") {
+			return false
+		}
+	} else if among_var == 3 {
+		// (, line 176
+		// <-, line 176
+		if !env.SliceFrom("die") {
+			return false
+		}
+	} else if among_var == 4 {
+		// (, line 177
+		// <-, line 177
+		if !env.SliceFrom("lie") {
+			return false
+		}
+	} else if among_var == 5 {
+		// (, line 178
+		// <-, line 178
+		if !env.SliceFrom("tie") {
+			return false
+		}
+	} else if among_var == 6 {
+		// (, line 182
+		// <-, line 182
+		if !env.SliceFrom("idl") {
+			return false
+		}
+	} else if among_var == 7 {
+		// (, line 183
+		// <-, line 183
+		if !env.SliceFrom("gentl") {
+			return false
+		}
+	} else if among_var == 8 {
+		// (, line 184
+		// <-, line 184
+		if !env.SliceFrom("ugli") {
+			return false
+		}
+	} else if among_var == 9 {
+		// (, line 185
+		// <-, line 185
+		if !env.SliceFrom("earli") {
+			return false
+		}
+	} else if among_var == 10 {
+		// (, line 186
+		// <-, line 186
+		if !env.SliceFrom("onli") {
+			return false
+		}
+	} else if among_var == 11 {
+		// (, line 187
+		// <-, line 187
+		if !env.SliceFrom("singl") {
+			return false
+		}
+	}
+	return true
+}
+
+func r_postlude(env *snowballRuntime.Env, ctx interface{}) bool {
+	context := ctx.(*Context)
+	_ = context
+	// (, line 203
+	// Boolean test Y_found, line 203
+	if !context.b_Y_found {
+		return false
+	}
+	// repeat, line 203
+replab0:
+	for {
+		var v_1 = env.Cursor
+	lab1:
+		for range [2]struct{}{} {
+			// (, line 203
+			// goto, line 203
+		golab2:
+			for {
+				var v_2 = env.Cursor
+			lab3:
+				for {
+					// (, line 203
+					// [, line 203
+					env.Bra = env.Cursor
+					// literal, line 203
+					if !env.EqS("Y") {
+						break lab3
+					}
+					// ], line 203
+					env.Ket = env.Cursor
+					env.Cursor = v_2
+					break golab2
+				}
+				env.Cursor = v_2
+				if env.Cursor >= env.Limit {
+					break lab1
+				}
+				env.NextChar()
+			}
+			// <-, line 203
+			if !env.SliceFrom("y") {
+				return false
+			}
+			continue replab0
+		}
+		env.Cursor = v_1
+		break replab0
+	}
+	return true
+}
+
+func Stem(env *snowballRuntime.Env) bool {
+	var context = &Context{
+		b_Y_found: false,
+		i_p2:      0,
+		i_p1:      0,
+	}
+	_ = context
+	// (, line 205
+	// or, line 207
+lab0:
+	for {
+		var v_1 = env.Cursor
+	lab1:
+		for {
+			// call exception1, line 207
+			if !r_exception1(env, context) {
+				break lab1
+			}
+			break lab0
+		}
+		env.Cursor = v_1
+	lab2:
+		for {
+			// not, line 208
+			var v_2 = env.Cursor
+		lab3:
+			for {
+				{
+					// hop, line 208
+					var c = env.ByteIndexForHop((3))
+					if int32(0) > c || c > int32(env.Limit) {
+						break lab3
+					}
+					env.Cursor = int(c)
+				}
+				break lab2
+			}
+			env.Cursor = v_2
+			break lab0
+		}
+		env.Cursor = v_1
+		// (, line 208
+		// do, line 209
+		var v_3 = env.Cursor
+	lab4:
+		for {
+			// call prelude, line 209
+			if !r_prelude(env, context) {
+				break lab4
+			}
+			break lab4
+		}
+		env.Cursor = v_3
+		// do, line 210
+		var v_4 = env.Cursor
+	lab5:
+		for {
+			// call mark_regions, line 210
+			if !r_mark_regions(env, context) {
+				break lab5
+			}
+			break lab5
+		}
+		env.Cursor = v_4
+		// backwards, line 211
+		env.LimitBackward = env.Cursor
+		env.Cursor = env.Limit
+		// (, line 211
+		// do, line 213
+		var v_5 = env.Limit - env.Cursor
+	lab6:
+		for {
+			// call Step_1a, line 213
+			if !r_Step_1a(env, context) {
+				break lab6
+			}
+			break lab6
+		}
+		env.Cursor = env.Limit - v_5
+		// or, line 215
+	lab7:
+		for {
+			var v_6 = env.Limit - env.Cursor
+		lab8:
+			for {
+				// call exception2, line 215
+				if !r_exception2(env, context) {
+					break lab8
+				}
+				break lab7
+			}
+			env.Cursor = env.Limit - v_6
+			// (, line 215
+			// do, line 217
+			var v_7 = env.Limit - env.Cursor
+		lab9:
+			for {
+				// call Step_1b, line 217
+				if !r_Step_1b(env, context) {
+					break lab9
+				}
+				break lab9
+			}
+			env.Cursor = env.Limit - v_7
+			// do, line 218
+			var v_8 = env.Limit - env.Cursor
+		lab10:
+			for {
+				// call Step_1c, line 218
+				if !r_Step_1c(env, context) {
+					break lab10
+				}
+				break lab10
+			}
+			env.Cursor = env.Limit - v_8
+			// do, line 220
+			var v_9 = env.Limit - env.Cursor
+		lab11:
+			for {
+				// call Step_2, line 220
+				if !r_Step_2(env, context) {
+					break lab11
+				}
+				break lab11
+			}
+			env.Cursor = env.Limit - v_9
+			// do, line 221
+			var v_10 = env.Limit - env.Cursor
+		lab12:
+			for {
+				// call Step_3, line 221
+				if !r_Step_3(env, context) {
+					break lab12
+				}
+				break lab12
+			}
+			env.Cursor = env.Limit - v_10
+			// do, line 222
+			var v_11 = env.Limit - env.Cursor
+		lab13:
+			for {
+				// call Step_4, line 222
+				if !r_Step_4(env, context) {
+					break lab13
+				}
+				break lab13
+			}
+			env.Cursor = env.Limit - v_11
+			// do, line 224
+			var v_12 = env.Limit - env.Cursor
+		lab14:
+			for {
+				// call Step_5, line 224
+				if !r_Step_5(env, context) {
+					break lab14
+				}
+				break lab14
+			}
+			env.Cursor = env.Limit - v_12
+			break lab7
+		}
+		env.Cursor = env.LimitBackward
+		// do, line 227
+		var v_13 = env.Cursor
+	lab15:
+		for {
+			// call postlude, line 227
+			if !r_postlude(env, context) {
+				break lab15
+			}
+			break lab15
+		}
+		env.Cursor = v_13
+		break lab0
+	}
+	return true
+}
diff --git a/vendor/github.com/blevesearch/snowballstem/env.go b/vendor/github.com/blevesearch/snowballstem/env.go
new file mode 100644
index 0000000000..6636994ac7
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/env.go
@@ -0,0 +1,389 @@
+package snowballstem
+
+import (
+	"log"
+	"strings"
+	"unicode/utf8"
+)
+
+// Env represents the Snowball execution environment
+type Env struct {
+	current       string
+	Cursor        int
+	Limit         int
+	LimitBackward int
+	Bra           int
+	Ket           int
+}
+
+// NewEnv creates a new Snowball execution environment on the provided string
+func NewEnv(val string) *Env {
+	return &Env{
+		current:       val,
+		Cursor:        0,
+		Limit:         len(val),
+		LimitBackward: 0,
+		Bra:           0,
+		Ket:           len(val),
+	}
+}
+
+func (env *Env) Current() string {
+	return env.current
+}
+
+func (env *Env) SetCurrent(s string) {
+	env.current = s
+	env.Cursor = 0
+	env.Limit = len(s)
+	env.LimitBackward = 0
+	env.Bra = 0
+	env.Ket = len(s)
+}
+
+func (env *Env) ReplaceS(bra, ket int, s string) int32 {
+	adjustment := int32(len(s)) - (int32(ket) - int32(bra))
+	result, _ := splitAt(env.current, bra)
+	rsplit := ket
+	if ket < bra {
+		rsplit = bra
+	}
+	_, rhs := splitAt(env.current, rsplit)
+	result += s
+	result += rhs
+
+	newLim := int32(env.Limit) + adjustment
+	env.Limit = int(newLim)
+
+	if env.Cursor >= ket {
+		newCur := int32(env.Cursor) + adjustment
+		env.Cursor = int(newCur)
+	} else if env.Cursor > bra {
+		env.Cursor = bra
+	}
+
+	env.current = result
+	return adjustment
+}
+
+func (env *Env) EqS(s string) bool {
+	if env.Cursor >= env.Limit {
+		return false
+	}
+
+	if strings.HasPrefix(env.current[env.Cursor:], s) {
+		env.Cursor += len(s)
+		for !onCharBoundary(env.current, env.Cursor) {
+			env.Cursor++
+		}
+		return true
+	}
+	return false
+}
+
+func (env *Env) EqSB(s string) bool {
+	if int32(env.Cursor)-int32(env.LimitBackward) < int32(len(s)) {
+		return false
+	} else if !onCharBoundary(env.current, env.Cursor-len(s)) ||
+		!strings.HasPrefix(env.current[env.Cursor-len(s):], s) {
+		return false
+	} else {
+		env.Cursor -= len(s)
+		return true
+	}
+}
+
+func (env *Env) SliceFrom(s string) bool {
+	bra, ket := env.Bra, env.Ket
+	env.ReplaceS(bra, ket, s)
+	return true
+}
+
+func (env *Env) NextChar() {
+	env.Cursor++
+	for !onCharBoundary(env.current, env.Cursor) {
+		env.Cursor++
+	}
+}
+
+func (env *Env) PrevChar() {
+	env.Cursor--
+	for !onCharBoundary(env.current, env.Cursor) {
+		env.Cursor--
+	}
+}
+
+func (env *Env) ByteIndexForHop(delta int32) int32 {
+	if delta > 0 {
+		res := env.Cursor
+		for delta > 0 {
+			res++
+			delta--
+			for res <= len(env.current) && !onCharBoundary(env.current, res) {
+				res++
+			}
+		}
+		return int32(res)
+	} else if delta < 0 {
+		res := env.Cursor
+		for delta < 0 {
+			res--
+			delta++
+			for res >= 0 && !onCharBoundary(env.current, res) {
+				res--
+			}
+		}
+		return int32(res)
+	} else {
+		return int32(env.Cursor)
+	}
+}
+
+func (env *Env) InGrouping(chars []byte, min, max int32) bool {
+	if env.Cursor >= env.Limit {
+		return false
+	}
+
+	r, _ := utf8.DecodeRuneInString(env.current[env.Cursor:])
+	if r != utf8.RuneError {
+		if r > max || r < min {
+			return false
+		}
+		r -= min
+		if (chars[uint(r>>3)] & (0x1 << uint(r&0x7))) == 0 {
+			return false
+		}
+		env.NextChar()
+		return true
+	}
+	return false
+}
+
+func (env *Env) InGroupingB(chars []byte, min, max int32) bool {
+	if env.Cursor <= env.LimitBackward {
+		return false
+	}
+	env.PrevChar()
+	r, _ := utf8.DecodeRuneInString(env.current[env.Cursor:])
+	if r != utf8.RuneError {
+		env.NextChar()
+		if r > max || r < min {
+			return false
+		}
+		r -= min
+		if (chars[uint(r>>3)] & (0x1 << uint(r&0x7))) == 0 {
+			return false
+		}
+		env.PrevChar()
+		return true
+	}
+	return false
+}
+
+func (env *Env) OutGrouping(chars []byte, min, max int32) bool {
+	if env.Cursor >= env.Limit {
+		return false
+	}
+	r, _ := utf8.DecodeRuneInString(env.current[env.Cursor:])
+	if r != utf8.RuneError {
+		if r > max || r < min {
+			env.NextChar()
+			return true
+		}
+		r -= min
+		if (chars[uint(r>>3)] & (0x1 << uint(r&0x7))) == 0 {
+			env.NextChar()
+			return true
+		}
+	}
+	return false
+}
+
+func (env *Env) OutGroupingB(chars []byte, min, max int32) bool {
+	if env.Cursor <= env.LimitBackward {
+		return false
+	}
+	env.PrevChar()
+	r, _ := utf8.DecodeRuneInString(env.current[env.Cursor:])
+	if r != utf8.RuneError {
+		env.NextChar()
+		if r > max || r < min {
+			env.PrevChar()
+			return true
+		}
+		r -= min
+		if (chars[uint(r>>3)] & (0x1 << uint(r&0x7))) == 0 {
+			env.PrevChar()
+			return true
+		}
+	}
+	return false
+}
+
+func (env *Env) SliceDel() bool {
+	return env.SliceFrom("")
+}
+
+func (env *Env) Insert(bra, ket int, s string) {
+	adjustment := env.ReplaceS(bra, ket, s)
+	if bra <= env.Bra {
+		env.Bra = int(int32(env.Bra) + adjustment)
+	}
+	if bra <= env.Ket {
+		env.Ket = int(int32(env.Ket) + adjustment)
+	}
+}
+
+func (env *Env) SliceTo() string {
+	return env.current[env.Bra:env.Ket]
+}
+
+func (env *Env) FindAmong(amongs []*Among, ctx interface{}) int32 {
+	var i int32
+	j := int32(len(amongs))
+
+	c := env.Cursor
+	l := env.Limit
+
+	var commonI, commonJ int
+
+	firstKeyInspected := false
+	for {
+		k := i + ((j - i) >> 1)
+		var diff int32
+		common := min(commonI, commonJ)
+		w := amongs[k]
+		for lvar := common; lvar < len(w.Str); lvar++ {
+			if c+common == l {
+				diff--
+				break
+			}
+			diff = int32(env.current[c+common]) - int32(w.Str[lvar])
+			if diff != 0 {
+				break
+			}
+			common++
+		}
+		if diff < 0 {
+			j = k
+			commonJ = common
+		} else {
+			i = k
+			commonI = common
+		}
+		if j-i <= 1 {
+			if i > 0 {
+				break
+			}
+			if j == i {
+				break
+			}
+			if firstKeyInspected {
+				break
+			}
+			firstKeyInspected = true
+		}
+	}
+
+	for {
+		w := amongs[i]
+		if commonI >= len(w.Str) {
+			env.Cursor = c + len(w.Str)
+			if w.F != nil {
+				res := w.F(env, ctx)
+				env.Cursor = c + len(w.Str)
+				if res {
+					return w.B
+				}
+			} else {
+				return w.B
+			}
+		}
+		i = w.A
+		if i < 0 {
+			return 0
+		}
+	}
+}
+
+func (env *Env) FindAmongB(amongs []*Among, ctx interface{}) int32 {
+	var i int32
+	j := int32(len(amongs))
+
+	c := env.Cursor
+	lb := env.LimitBackward
+
+	var commonI, commonJ int
+
+	firstKeyInspected := false
+
+	for {
+		k := i + ((j - i) >> 1)
+		diff := int32(0)
+		common := min(commonI, commonJ)
+		w := amongs[k]
+		for lvar := len(w.Str) - int(common) - 1; lvar >= 0; lvar-- {
+			if c-common == lb {
+				diff--
+				break
+			}
+			diff = int32(env.current[c-common-1]) - int32(w.Str[lvar])
+			if diff != 0 {
+				break
+			}
+			// Count up commons. But not one character but the byte width of that char
+			common++
+		}
+		if diff < 0 {
+			j = k
+			commonJ = common
+		} else {
+			i = k
+			commonI = common
+		}
+		if j-i <= 1 {
+			if i > 0 {
+				break
+			}
+			if j == i {
+				break
+			}
+			if firstKeyInspected {
+				break
+			}
+			firstKeyInspected = true
+		}
+	}
+	for {
+		w := amongs[i]
+		if commonI >= len(w.Str) {
+			env.Cursor = c - len(w.Str)
+			if w.F != nil {
+				res := w.F(env, ctx)
+				env.Cursor = c - len(w.Str)
+				if res {
+					return w.B
+				}
+			} else {
+				return w.B
+			}
+		}
+		i = w.A
+		if i < 0 {
+			return 0
+		}
+	}
+}
+
+func (env *Env) Debug(count, lineNumber int) {
+	log.Printf("snowball debug, count: %d, line: %d", count, lineNumber)
+}
+
+func (env *Env) Clone() *Env {
+	clone := *env
+	return &clone
+}
+
+func (env *Env) AssignTo() string {
+	return env.Current()
+}
diff --git a/vendor/github.com/blevesearch/snowballstem/gen.go b/vendor/github.com/blevesearch/snowballstem/gen.go
new file mode 100644
index 0000000000..92548b0010
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/gen.go
@@ -0,0 +1,61 @@
+package snowballstem
+
+// to regenerate these commands, run
+// go run gengen.go /path/to/snowball/algorithms/directory
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/arabic/stem_Unicode.sbl -go -o arabic/arabic_stemmer -gop arabic -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w arabic/arabic_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/danish/stem_ISO_8859_1.sbl -go -o danish/danish_stemmer -gop danish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w danish/danish_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/dutch/stem_ISO_8859_1.sbl -go -o dutch/dutch_stemmer -gop dutch -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w dutch/dutch_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/english/stem_ISO_8859_1.sbl -go -o english/english_stemmer -gop english -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w english/english_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/finnish/stem_ISO_8859_1.sbl -go -o finnish/finnish_stemmer -gop finnish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w finnish/finnish_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/french/stem_ISO_8859_1.sbl -go -o french/french_stemmer -gop french -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w french/french_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/german/stem_ISO_8859_1.sbl -go -o german/german_stemmer -gop german -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w german/german_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/hungarian/stem_Unicode.sbl -go -o hungarian/hungarian_stemmer -gop hungarian -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w hungarian/hungarian_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/irish/stem_ISO_8859_1.sbl -go -o irish/irish_stemmer -gop irish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w irish/irish_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/italian/stem_ISO_8859_1.sbl -go -o italian/italian_stemmer -gop italian -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w italian/italian_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/norwegian/stem_ISO_8859_1.sbl -go -o norwegian/norwegian_stemmer -gop norwegian -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w norwegian/norwegian_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/porter/stem_ISO_8859_1.sbl -go -o porter/porter_stemmer -gop porter -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w porter/porter_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/portuguese/stem_ISO_8859_1.sbl -go -o portuguese/portuguese_stemmer -gop portuguese -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w portuguese/portuguese_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/romanian/stem_Unicode.sbl -go -o romanian/romanian_stemmer -gop romanian -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w romanian/romanian_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/russian/stem_Unicode.sbl -go -o russian/russian_stemmer -gop russian -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w russian/russian_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/spanish/stem_ISO_8859_1.sbl -go -o spanish/spanish_stemmer -gop spanish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w spanish/spanish_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/swedish/stem_ISO_8859_1.sbl -go -o swedish/swedish_stemmer -gop swedish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w swedish/swedish_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/tamil/stem_Unicode.sbl -go -o tamil/tamil_stemmer -gop tamil -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w tamil/tamil_stemmer.go
+
+//go:generate $SNOWBALL/snowball $SNOWBALL/algorithms/turkish/stem_Unicode.sbl -go -o turkish/turkish_stemmer -gop turkish -gor github.com/blevesearch/snowballstem
+//go:generate gofmt -s -w turkish/turkish_stemmer.go
diff --git a/vendor/github.com/blevesearch/snowballstem/go.mod b/vendor/github.com/blevesearch/snowballstem/go.mod
new file mode 100644
index 0000000000..12218e2d67
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/go.mod
@@ -0,0 +1,3 @@
+module github.com/blevesearch/snowballstem
+
+go 1.13
diff --git a/vendor/github.com/blevesearch/snowballstem/util.go b/vendor/github.com/blevesearch/snowballstem/util.go
new file mode 100644
index 0000000000..7c68f6e750
--- /dev/null
+++ b/vendor/github.com/blevesearch/snowballstem/util.go
@@ -0,0 +1,34 @@
+package snowballstem
+
+import (
+	"math"
+	"unicode/utf8"
+)
+
+const MaxInt = math.MaxInt32
+const MinInt = math.MinInt32
+
+func splitAt(str string, mid int) (string, string) {
+	return str[:mid], str[mid:]
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func onCharBoundary(s string, pos int) bool {
+	if pos <= 0 || pos >= len(s) {
+		return true
+	}
+	return utf8.RuneStart(s[pos])
+}
+
+// RuneCountInString is a wrapper around utf8.RuneCountInString
+// this allows us to not have to conditionally include
+// the utf8 package into some stemmers and not others
+func RuneCountInString(str string) int {
+	return utf8.RuneCountInString(str)
+}
diff --git a/vendor/github.com/blevesearch/zap/v11/.gitignore b/vendor/github.com/blevesearch/zap/v11/.gitignore
new file mode 100644
index 0000000000..46d1cfad54
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v11/.gitignore
@@ -0,0 +1,12 @@
+#*
+*.sublime-*
+*~
+.#*
+.project
+.settings
+**/.idea/
+**/*.iml
+.DS_Store
+/cmd/zap/zap
+*.test
+tags
diff --git a/vendor/github.com/blevesearch/zap/v11/LICENSE b/vendor/github.com/blevesearch/zap/v11/LICENSE
new file mode 100644
index 0000000000..7a4a3ea242
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v11/LICENSE
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
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+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
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+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
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+   3. Grant of Patent License. Subject to the terms and conditions of
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
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+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
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+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
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+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
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+          of the NOTICE file are for informational purposes only and
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+          notices within Derivative Works that You distribute, alongside
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+          that such additional attribution notices cannot be construed
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
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+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
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+      negligent acts) or agreed to in writing, shall any Contributor be
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+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
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+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
\ No newline at end of file
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/README.md b/vendor/github.com/blevesearch/zap/v11/README.md
index 0facb669fd..0facb669fd 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/README.md
+++ b/vendor/github.com/blevesearch/zap/v11/README.md
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/build.go b/vendor/github.com/blevesearch/zap/v11/build.go
index c02333cee0..bac1edb549 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/build.go
+++ b/vendor/github.com/blevesearch/zap/v11/build.go
@@ -16,9 +16,10 @@ package zap
 
 import (
 	"bufio"
-	"github.com/couchbase/vellum"
 	"math"
 	"os"
+
+	"github.com/couchbase/vellum"
 )
 
 const Version uint32 = 11
@@ -27,6 +28,10 @@ const Type string = "zap"
 
 const fieldNotUninverted = math.MaxUint64
 
+func (sb *SegmentBase) Persist(path string) error {
+	return PersistSegmentBase(sb, path)
+}
+
 // PersistSegmentBase persists SegmentBase in the zap file format.
 func PersistSegmentBase(sb *SegmentBase, path string) error {
 	flag := os.O_RDWR | os.O_CREATE
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/contentcoder.go b/vendor/github.com/blevesearch/zap/v11/contentcoder.go
index b9ff8179b3..b9ff8179b3 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/contentcoder.go
+++ b/vendor/github.com/blevesearch/zap/v11/contentcoder.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/count.go b/vendor/github.com/blevesearch/zap/v11/count.go
index 50290f8882..50290f8882 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/count.go
+++ b/vendor/github.com/blevesearch/zap/v11/count.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/dict.go b/vendor/github.com/blevesearch/zap/v11/dict.go
index ad4a8f8dc5..ad4a8f8dc5 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/dict.go
+++ b/vendor/github.com/blevesearch/zap/v11/dict.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/docvalues.go b/vendor/github.com/blevesearch/zap/v11/docvalues.go
index a819ca239f..2566dc6d8c 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/docvalues.go
+++ b/vendor/github.com/blevesearch/zap/v11/docvalues.go
@@ -76,10 +76,6 @@ func (di *docValueReader) cloneInto(rv *docValueReader) *docValueReader {
 	return rv
 }
 
-func (di *docValueReader) fieldName() string {
-	return di.field
-}
-
 func (di *docValueReader) curChunkNumber() uint64 {
 	return di.curChunkNum
 }
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/enumerator.go b/vendor/github.com/blevesearch/zap/v11/enumerator.go
index cd6ff73c79..cd6ff73c79 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/enumerator.go
+++ b/vendor/github.com/blevesearch/zap/v11/enumerator.go
diff --git a/vendor/github.com/blevesearch/zap/v11/go.mod b/vendor/github.com/blevesearch/zap/v11/go.mod
new file mode 100644
index 0000000000..a238188e66
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v11/go.mod
@@ -0,0 +1,12 @@
+module github.com/blevesearch/zap/v11
+
+go 1.12
+
+require (
+	github.com/RoaringBitmap/roaring v0.4.21
+	github.com/blevesearch/bleve v1.0.7
+	github.com/blevesearch/mmap-go v1.0.2
+	github.com/couchbase/vellum v1.0.1
+	github.com/golang/snappy v0.0.1
+	github.com/spf13/cobra v0.0.5
+)
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/intcoder.go b/vendor/github.com/blevesearch/zap/v11/intcoder.go
index 571d06edb6..571d06edb6 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/intcoder.go
+++ b/vendor/github.com/blevesearch/zap/v11/intcoder.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/merge.go b/vendor/github.com/blevesearch/zap/v11/merge.go
index 50bd7207a5..0d3f5458a2 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/merge.go
+++ b/vendor/github.com/blevesearch/zap/v11/merge.go
@@ -31,32 +31,30 @@ import (
 
 var DefaultFileMergerBufferSize = 1024 * 1024
 
-// ValidateMerge can be set by applications to perform additional checks
-// on a new segment produced by a merge, by default this does nothing.
-// Caller should provide EITHER segments or memSegments, but not both.
-// This API is experimental and may be removed at any time.
-var ValidateMerge = func(segments []*Segment, memSegments []*SegmentBase, drops []*roaring.Bitmap, newSegment *Segment) error {
-	return nil
-}
-
 const docDropped = math.MaxUint64 // sentinel docNum to represent a deleted doc
 
-// Merge takes a slice of zap segments and bit masks describing which
+// Merge takes a slice of segments and bit masks describing which
 // documents may be dropped, and creates a new segment containing the
-// remaining data.  This new segment is built at the specified path,
-// with the provided chunkFactor.
-func Merge(segments []*Segment, drops []*roaring.Bitmap, path string,
-	chunkFactor uint32, closeCh chan struct{}, s seg.StatsReporter) (
+// remaining data.  This new segment is built at the specified path.
+func (*ZapPlugin) Merge(segments []seg.Segment, drops []*roaring.Bitmap, path string,
+	closeCh chan struct{}, s seg.StatsReporter) (
 	[][]uint64, uint64, error) {
+
 	segmentBases := make([]*SegmentBase, len(segments))
 	for segmenti, segment := range segments {
-		segmentBases[segmenti] = &segment.SegmentBase
+		switch segmentx := segment.(type) {
+		case *Segment:
+			segmentBases[segmenti] = &segmentx.SegmentBase
+		case *SegmentBase:
+			segmentBases[segmenti] = segmentx
+		default:
+			panic(fmt.Sprintf("oops, unexpected segment type: %T", segment))
+		}
 	}
-
-	return MergeSegmentBases(segmentBases, drops, path, chunkFactor, closeCh, s)
+	return mergeSegmentBases(segmentBases, drops, path, defaultChunkFactor, closeCh, s)
 }
 
-func MergeSegmentBases(segmentBases []*SegmentBase, drops []*roaring.Bitmap, path string,
+func mergeSegmentBases(segmentBases []*SegmentBase, drops []*roaring.Bitmap, path string,
 	chunkFactor uint32, closeCh chan struct{}, s seg.StatsReporter) (
 	[][]uint64, uint64, error) {
 	flag := os.O_RDWR | os.O_CREATE
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/new.go b/vendor/github.com/blevesearch/zap/v11/new.go
index c108ec16dd..6c75f2fd16 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/new.go
+++ b/vendor/github.com/blevesearch/zap/v11/new.go
@@ -25,6 +25,7 @@ import (
 	"github.com/blevesearch/bleve/analysis"
 	"github.com/blevesearch/bleve/document"
 	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/index/scorch/segment"
 	"github.com/couchbase/vellum"
 	"github.com/golang/snappy"
 )
@@ -41,10 +42,17 @@ var ValidateDocFields = func(field document.Field) error {
 	return nil
 }
 
+var defaultChunkFactor uint32 = 1024
+
 // AnalysisResultsToSegmentBase produces an in-memory zap-encoded
 // SegmentBase from analysis results
-func AnalysisResultsToSegmentBase(results []*index.AnalysisResult,
-	chunkFactor uint32) (*SegmentBase, uint64, error) {
+func (z *ZapPlugin) New(results []*index.AnalysisResult) (
+	segment.Segment, uint64, error) {
+	return z.newWithChunkFactor(results, defaultChunkFactor)
+}
+
+func (*ZapPlugin) newWithChunkFactor(results []*index.AnalysisResult,
+	chunkFactor uint32) (segment.Segment, uint64, error) {
 	s := interimPool.Get().(*interim)
 
 	var br bytes.Buffer
diff --git a/vendor/github.com/blevesearch/zap/v11/plugin.go b/vendor/github.com/blevesearch/zap/v11/plugin.go
new file mode 100644
index 0000000000..38a0638d4d
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v11/plugin.go
@@ -0,0 +1,37 @@
+//  Copyright (c) 2020 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"github.com/blevesearch/bleve/index/scorch/segment"
+)
+
+// ZapPlugin implements the Plugin interface of
+// the blevesearch/bleve/index/scorch/segment pkg
+type ZapPlugin struct{}
+
+func (*ZapPlugin) Type() string {
+	return Type
+}
+
+func (*ZapPlugin) Version() uint32 {
+	return Version
+}
+
+// Plugin returns an instance segment.Plugin for use
+// by the Scorch indexing scheme
+func Plugin() segment.Plugin {
+	return &ZapPlugin{}
+}
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/posting.go b/vendor/github.com/blevesearch/zap/v11/posting.go
index 4c43fdb9b9..619dc4c323 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/posting.go
+++ b/vendor/github.com/blevesearch/zap/v11/posting.go
@@ -793,10 +793,23 @@ func (p *PostingsIterator) DocNum1Hit() (uint64, bool) {
 	return 0, false
 }
 
+// ActualBitmap returns the underlying actual bitmap
+// which can be used up the stack for optimizations
+func (p *PostingsIterator) ActualBitmap() *roaring.Bitmap {
+	return p.ActualBM
+}
+
+// ReplaceActual replaces the ActualBM with the provided
+// bitmap
+func (p *PostingsIterator) ReplaceActual(abm *roaring.Bitmap) {
+	p.ActualBM = abm
+	p.Actual = abm.Iterator()
+}
+
 // PostingsIteratorFromBitmap constructs a PostingsIterator given an
 // "actual" bitmap.
 func PostingsIteratorFromBitmap(bm *roaring.Bitmap,
-	includeFreqNorm, includeLocs bool) (*PostingsIterator, error) {
+	includeFreqNorm, includeLocs bool) (segment.PostingsIterator, error) {
 	return &PostingsIterator{
 		ActualBM:        bm,
 		Actual:          bm.Iterator(),
@@ -807,11 +820,11 @@ func PostingsIteratorFromBitmap(bm *roaring.Bitmap,
 
 // PostingsIteratorFrom1Hit constructs a PostingsIterator given a
 // 1-hit docNum.
-func PostingsIteratorFrom1Hit(docNum1Hit, normBits1Hit uint64,
-	includeFreqNorm, includeLocs bool) (*PostingsIterator, error) {
+func PostingsIteratorFrom1Hit(docNum1Hit uint64,
+	includeFreqNorm, includeLocs bool) (segment.PostingsIterator, error) {
 	return &PostingsIterator{
 		docNum1Hit:      docNum1Hit,
-		normBits1Hit:    normBits1Hit,
+		normBits1Hit:    NormBits1Hit,
 		includeFreqNorm: includeFreqNorm,
 		includeLocs:     includeLocs,
 	}, nil
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/read.go b/vendor/github.com/blevesearch/zap/v11/read.go
index e47d4c6abd..e47d4c6abd 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/read.go
+++ b/vendor/github.com/blevesearch/zap/v11/read.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/segment.go b/vendor/github.com/blevesearch/zap/v11/segment.go
index 5aa33a26c9..517b6afbfc 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/segment.go
+++ b/vendor/github.com/blevesearch/zap/v11/segment.go
@@ -27,7 +27,7 @@ import (
 	"github.com/blevesearch/bleve/index/scorch/segment"
 	"github.com/blevesearch/bleve/size"
 	"github.com/couchbase/vellum"
-	mmap "github.com/edsrzf/mmap-go"
+	mmap "github.com/blevesearch/mmap-go"
 	"github.com/golang/snappy"
 )
 
@@ -39,7 +39,7 @@ func init() {
 }
 
 // Open returns a zap impl of a segment
-func Open(path string) (segment.Segment, error) {
+func (*ZapPlugin) Open(path string) (segment.Segment, error) {
 	f, err := os.Open(path)
 	if err != nil {
 		return nil, err
@@ -116,7 +116,7 @@ func (sb *SegmentBase) updateSize() {
 		cap(sb.mem)
 
 	// fieldsMap
-	for k, _ := range sb.fieldsMap {
+	for k := range sb.fieldsMap {
 		sizeInBytes += (len(k) + size.SizeOfString) + size.SizeOfUint16
 	}
 
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/write.go b/vendor/github.com/blevesearch/zap/v11/write.go
index cddaedd007..cddaedd007 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/write.go
+++ b/vendor/github.com/blevesearch/zap/v11/write.go
diff --git a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/zap.md b/vendor/github.com/blevesearch/zap/v11/zap.md
index d74dc548b8..d74dc548b8 100644
--- a/vendor/github.com/blevesearch/bleve/index/scorch/segment/zap/zap.md
+++ b/vendor/github.com/blevesearch/zap/v11/zap.md
diff --git a/vendor/github.com/blevesearch/zap/v12/.gitignore b/vendor/github.com/blevesearch/zap/v12/.gitignore
new file mode 100644
index 0000000000..46d1cfad54
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/.gitignore
@@ -0,0 +1,12 @@
+#*
+*.sublime-*
+*~
+.#*
+.project
+.settings
+**/.idea/
+**/*.iml
+.DS_Store
+/cmd/zap/zap
+*.test
+tags
diff --git a/vendor/github.com/blevesearch/zap/v12/LICENSE b/vendor/github.com/blevesearch/zap/v12/LICENSE
new file mode 100644
index 0000000000..7a4a3ea242
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/LICENSE
@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
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+      Work and such Derivative Works in Source or Object form.
+
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
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+      institute patent litigation against any entity (including a
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+
+   4. Redistribution. You may reproduce and distribute copies of the
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+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
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+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
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+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
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+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
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+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
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+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
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+
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+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
\ No newline at end of file
diff --git a/vendor/github.com/blevesearch/zap/v12/README.md b/vendor/github.com/blevesearch/zap/v12/README.md
new file mode 100644
index 0000000000..0facb669fd
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/README.md
@@ -0,0 +1,158 @@
+# zap file format
+
+Advanced ZAP File Format Documentation is [here](zap.md).
+
+The file is written in the reverse order that we typically access data.  This helps us write in one pass since later sections of the file require file offsets of things we've already written.
+
+Current usage:
+
+- mmap the entire file
+- crc-32 bytes and version are in fixed position at end of the file
+- reading remainder of footer could be version specific
+- remainder of footer gives us:
+  - 3 important offsets (docValue , fields index and stored data index)
+  - 2 important values (number of docs and chunk factor)
+- field data is processed once and memoized onto the heap so that we never have to go back to disk for it
+- access to stored data by doc number means first navigating to the stored data index, then accessing a fixed position offset into that slice, which gives us the actual address of the data.  the first bytes of that section tell us the size of data so that we know where it ends.
+- access to all other indexed data follows the following pattern:
+  - first know the field name -> convert to id
+  - next navigate to term dictionary for that field
+    - some operations stop here and do dictionary ops
+  - next use dictionary to navigate to posting list for a specific term
+  - walk posting list
+  - if necessary, walk posting details as we go
+  - if location info is desired, consult location bitmap to see if it is there
+
+## stored fields section
+
+- for each document
+  - preparation phase:
+    - produce a slice of metadata bytes and data bytes
+    - produce these slices in field id order
+    - field value is appended to the data slice
+    - metadata slice is varint encoded with the following values for each field value
+      - field id (uint16)
+      - field type (byte)
+      - field value start offset in uncompressed data slice (uint64)
+      - field value length (uint64)
+      - field number of array positions (uint64)
+      - one additional value for each array position (uint64)
+      - compress the data slice using snappy
+  - file writing phase:
+    - remember the start offset for this document
+    - write out meta data length (varint uint64)
+    - write out compressed data length (varint uint64)
+    - write out the metadata bytes
+    - write out the compressed data bytes
+
+## stored fields idx
+
+- for each document
+  - write start offset (remembered from previous section) of stored data (big endian uint64)
+
+With this index and a known document number, we have direct access to all the stored field data.
+
+## posting details (freq/norm) section
+
+- for each posting list
+  - produce a slice containing multiple consecutive chunks (each chunk is varint stream)
+  - produce a slice remembering offsets of where each chunk starts
+  - preparation phase:
+    - for each hit in the posting list
+    - if this hit is in next chunk close out encoding of last chunk and record offset start of next
+    - encode term frequency (uint64)
+    - encode norm factor (float32)
+  - file writing phase:
+    - remember start position for this posting list details
+    - write out number of chunks that follow (varint uint64)
+    - write out length of each chunk (each a varint uint64)
+    - write out the byte slice containing all the chunk data
+
+If you know the doc number you're interested in, this format lets you jump to the correct chunk (docNum/chunkFactor) directly and then seek within that chunk until you find it.
+
+## posting details (location) section
+
+- for each posting list
+  - produce a slice containing multiple consecutive chunks (each chunk is varint stream)
+  - produce a slice remembering offsets of where each chunk starts
+  - preparation phase:
+    - for each hit in the posting list
+    - if this hit is in next chunk close out encoding of last chunk and record offset start of next
+    - encode field (uint16)
+    - encode field pos (uint64)
+    - encode field start (uint64)
+    - encode field end (uint64)
+    - encode number of array positions to follow (uint64)
+    - encode each array position (each uint64)
+  - file writing phase:
+    - remember start position for this posting list details
+    - write out number of chunks that follow (varint uint64)
+    - write out length of each chunk (each a varint uint64)
+    - write out the byte slice containing all the chunk data
+
+If you know the doc number you're interested in, this format lets you jump to the correct chunk (docNum/chunkFactor) directly and then seek within that chunk until you find it.
+
+## postings list section
+
+- for each posting list
+  - preparation phase:
+    - encode roaring bitmap posting list to bytes (so we know the length)
+  - file writing phase:
+    - remember the start position for this posting list
+    - write freq/norm details offset (remembered from previous, as varint uint64)
+    - write location details offset (remembered from previous, as varint uint64)
+    - write length of encoded roaring bitmap
+    - write the serialized roaring bitmap data
+
+## dictionary
+
+- for each field
+  - preparation phase:
+    - encode vellum FST with dictionary data pointing to file offset of posting list (remembered from previous)
+  - file writing phase:
+    - remember the start position of this persistDictionary
+    - write length of vellum data (varint uint64)
+    - write out vellum data
+
+## fields section
+
+- for each field
+  - file writing phase:
+    - remember start offset for each field
+    - write dictionary address (remembered from previous) (varint uint64)
+    - write length of field name (varint uint64)
+    - write field name bytes
+
+## fields idx
+
+- for each field
+  - file writing phase:
+    - write big endian uint64 of start offset for each field
+
+NOTE: currently we don't know or record the length of this fields index.  Instead we rely on the fact that we know it immediately precedes a footer of known size.
+
+## fields DocValue
+
+- for each field
+  - preparation phase:
+    - produce a slice containing multiple consecutive chunks, where each chunk is composed of a meta section followed by compressed columnar field data
+    - produce a slice remembering the length of each chunk
+  - file writing phase:
+    - remember the start position of this first field DocValue offset in the footer
+    - write out number of chunks that follow (varint uint64)
+    - write out length of each chunk (each a varint uint64)
+    - write out the byte slice containing all the chunk data
+
+NOTE: currently the meta header inside each chunk gives clue to the location offsets and size of the data pertaining to a given docID and any
+read operation leverage that meta information to extract the document specific data from the file.
+
+## footer
+
+- file writing phase
+  - write number of docs (big endian uint64)
+  - write stored field index location (big endian uint64)
+  - write field index location (big endian uint64)
+  - write field docValue location (big endian uint64)
+  - write out chunk factor (big endian uint32)
+  - write out version (big endian uint32)
+  - write out file CRC of everything preceding this (big endian uint32)
diff --git a/vendor/github.com/blevesearch/zap/v12/build.go b/vendor/github.com/blevesearch/zap/v12/build.go
new file mode 100644
index 0000000000..467e5e007b
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/build.go
@@ -0,0 +1,156 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bufio"
+	"math"
+	"os"
+
+	"github.com/couchbase/vellum"
+)
+
+const Version uint32 = 12
+
+const Type string = "zap"
+
+const fieldNotUninverted = math.MaxUint64
+
+func (sb *SegmentBase) Persist(path string) error {
+	return PersistSegmentBase(sb, path)
+}
+
+// PersistSegmentBase persists SegmentBase in the zap file format.
+func PersistSegmentBase(sb *SegmentBase, path string) error {
+	flag := os.O_RDWR | os.O_CREATE
+
+	f, err := os.OpenFile(path, flag, 0600)
+	if err != nil {
+		return err
+	}
+
+	cleanup := func() {
+		_ = f.Close()
+		_ = os.Remove(path)
+	}
+
+	br := bufio.NewWriter(f)
+
+	_, err = br.Write(sb.mem)
+	if err != nil {
+		cleanup()
+		return err
+	}
+
+	err = persistFooter(sb.numDocs, sb.storedIndexOffset, sb.fieldsIndexOffset, sb.docValueOffset,
+		sb.chunkMode, sb.memCRC, br)
+	if err != nil {
+		cleanup()
+		return err
+	}
+
+	err = br.Flush()
+	if err != nil {
+		cleanup()
+		return err
+	}
+
+	err = f.Sync()
+	if err != nil {
+		cleanup()
+		return err
+	}
+
+	err = f.Close()
+	if err != nil {
+		cleanup()
+		return err
+	}
+
+	return nil
+}
+
+func persistStoredFieldValues(fieldID int,
+	storedFieldValues [][]byte, stf []byte, spf [][]uint64,
+	curr int, metaEncode varintEncoder, data []byte) (
+	int, []byte, error) {
+	for i := 0; i < len(storedFieldValues); i++ {
+		// encode field
+		_, err := metaEncode(uint64(fieldID))
+		if err != nil {
+			return 0, nil, err
+		}
+		// encode type
+		_, err = metaEncode(uint64(stf[i]))
+		if err != nil {
+			return 0, nil, err
+		}
+		// encode start offset
+		_, err = metaEncode(uint64(curr))
+		if err != nil {
+			return 0, nil, err
+		}
+		// end len
+		_, err = metaEncode(uint64(len(storedFieldValues[i])))
+		if err != nil {
+			return 0, nil, err
+		}
+		// encode number of array pos
+		_, err = metaEncode(uint64(len(spf[i])))
+		if err != nil {
+			return 0, nil, err
+		}
+		// encode all array positions
+		for _, pos := range spf[i] {
+			_, err = metaEncode(pos)
+			if err != nil {
+				return 0, nil, err
+			}
+		}
+
+		data = append(data, storedFieldValues[i]...)
+		curr += len(storedFieldValues[i])
+	}
+
+	return curr, data, nil
+}
+
+func InitSegmentBase(mem []byte, memCRC uint32, chunkMode uint32,
+	fieldsMap map[string]uint16, fieldsInv []string, numDocs uint64,
+	storedIndexOffset uint64, fieldsIndexOffset uint64, docValueOffset uint64,
+	dictLocs []uint64) (*SegmentBase, error) {
+	sb := &SegmentBase{
+		mem:               mem,
+		memCRC:            memCRC,
+		chunkMode:         chunkMode,
+		fieldsMap:         fieldsMap,
+		fieldsInv:         fieldsInv,
+		numDocs:           numDocs,
+		storedIndexOffset: storedIndexOffset,
+		fieldsIndexOffset: fieldsIndexOffset,
+		docValueOffset:    docValueOffset,
+		dictLocs:          dictLocs,
+		fieldDvReaders:    make(map[uint16]*docValueReader),
+		fieldFSTs:         make(map[uint16]*vellum.FST),
+	}
+	sb.updateSize()
+
+	err := sb.loadDvReaders()
+	if err != nil {
+		return nil, err
+	}
+
+	return sb, nil
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/chunk.go b/vendor/github.com/blevesearch/zap/v12/chunk.go
new file mode 100644
index 0000000000..fe9f398da6
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/chunk.go
@@ -0,0 +1,54 @@
+//  Copyright (c) 2019 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//              http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"fmt"
+)
+
+// LegacyChunkMode was the original chunk mode (always chunk size 1024)
+// this mode is still used for chunking doc values.
+var LegacyChunkMode uint32 = 1024
+
+// DefaultChunkMode is the most recent improvement to chunking and should
+// be used by default.
+var DefaultChunkMode uint32 = 1025
+
+func getChunkSize(chunkMode uint32, cardinality uint64, maxDocs uint64) (uint64, error) {
+	switch {
+	// any chunkMode <= 1024 will always chunk with chunkSize=chunkMode
+	case chunkMode <= 1024:
+		// legacy chunk size
+		return uint64(chunkMode), nil
+
+	case chunkMode == 1025:
+		// attempt at simple improvement
+		// theory - the point of chunking is to put a bound on the maximum number of
+		// calls to Next() needed to find a random document.  ie, you should be able
+		// to do one jump to the correct chunk, and then walk through at most
+		// chunk-size items
+		// previously 1024 was chosen as the chunk size, but this is particularly
+		// wasteful for low cardinality terms.  the observation is that if there
+		// are less than 1024 items, why not put them all in one chunk,
+		// this way you'll still achieve the same goal of visiting at most
+		// chunk-size items.
+		// no attempt is made to tweak any other case
+		if cardinality <= 1024 {
+			return maxDocs, nil
+		}
+		return 1024, nil
+	}
+	return 0, fmt.Errorf("unknown chunk mode %d", chunkMode)
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/contentcoder.go b/vendor/github.com/blevesearch/zap/v12/contentcoder.go
new file mode 100644
index 0000000000..c145b5a113
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/contentcoder.go
@@ -0,0 +1,243 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io"
+	"reflect"
+
+	"github.com/golang/snappy"
+)
+
+var reflectStaticSizeMetaData int
+
+func init() {
+	var md MetaData
+	reflectStaticSizeMetaData = int(reflect.TypeOf(md).Size())
+}
+
+var termSeparator byte = 0xff
+var termSeparatorSplitSlice = []byte{termSeparator}
+
+type chunkedContentCoder struct {
+	final     []byte
+	chunkSize uint64
+	currChunk uint64
+	chunkLens []uint64
+
+	w                io.Writer
+	progressiveWrite bool
+
+	chunkMetaBuf bytes.Buffer
+	chunkBuf     bytes.Buffer
+
+	chunkMeta []MetaData
+
+	compressed []byte // temp buf for snappy compression
+}
+
+// MetaData represents the data information inside a
+// chunk.
+type MetaData struct {
+	DocNum      uint64 // docNum of the data inside the chunk
+	DocDvOffset uint64 // offset of data inside the chunk for the given docid
+}
+
+// newChunkedContentCoder returns a new chunk content coder which
+// packs data into chunks based on the provided chunkSize
+func newChunkedContentCoder(chunkSize uint64, maxDocNum uint64,
+	w io.Writer, progressiveWrite bool) *chunkedContentCoder {
+	total := maxDocNum/chunkSize + 1
+	rv := &chunkedContentCoder{
+		chunkSize:        chunkSize,
+		chunkLens:        make([]uint64, total),
+		chunkMeta:        make([]MetaData, 0, total),
+		w:                w,
+		progressiveWrite: progressiveWrite,
+	}
+
+	return rv
+}
+
+// Reset lets you reuse this chunked content coder. Buffers are reset
+// and re used. You cannot change the chunk size.
+func (c *chunkedContentCoder) Reset() {
+	c.currChunk = 0
+	c.final = c.final[:0]
+	c.chunkBuf.Reset()
+	c.chunkMetaBuf.Reset()
+	for i := range c.chunkLens {
+		c.chunkLens[i] = 0
+	}
+	c.chunkMeta = c.chunkMeta[:0]
+}
+
+func (c *chunkedContentCoder) SetChunkSize(chunkSize uint64, maxDocNum uint64) {
+	total := int(maxDocNum/chunkSize + 1)
+	c.chunkSize = chunkSize
+	if cap(c.chunkLens) < total {
+		c.chunkLens = make([]uint64, total)
+	} else {
+		c.chunkLens = c.chunkLens[:total]
+	}
+	if cap(c.chunkMeta) < total {
+		c.chunkMeta = make([]MetaData, 0, total)
+	}
+}
+
+// Close indicates you are done calling Add() this allows
+// the final chunk to be encoded.
+func (c *chunkedContentCoder) Close() error {
+	return c.flushContents()
+}
+
+func (c *chunkedContentCoder) flushContents() error {
+	// flush the contents, with meta information at first
+	buf := make([]byte, binary.MaxVarintLen64)
+	n := binary.PutUvarint(buf, uint64(len(c.chunkMeta)))
+	_, err := c.chunkMetaBuf.Write(buf[:n])
+	if err != nil {
+		return err
+	}
+
+	// write out the metaData slice
+	for _, meta := range c.chunkMeta {
+		_, err := writeUvarints(&c.chunkMetaBuf, meta.DocNum, meta.DocDvOffset)
+		if err != nil {
+			return err
+		}
+	}
+
+	// write the metadata to final data
+	metaData := c.chunkMetaBuf.Bytes()
+	c.final = append(c.final, c.chunkMetaBuf.Bytes()...)
+	// write the compressed data to the final data
+	c.compressed = snappy.Encode(c.compressed[:cap(c.compressed)], c.chunkBuf.Bytes())
+	c.final = append(c.final, c.compressed...)
+
+	c.chunkLens[c.currChunk] = uint64(len(c.compressed) + len(metaData))
+
+	if c.progressiveWrite {
+		_, err := c.w.Write(c.final)
+		if err != nil {
+			return err
+		}
+		c.final = c.final[:0]
+	}
+
+	return nil
+}
+
+// Add encodes the provided byte slice into the correct chunk for the provided
+// doc num.  You MUST call Add() with increasing docNums.
+func (c *chunkedContentCoder) Add(docNum uint64, vals []byte) error {
+	chunk := docNum / c.chunkSize
+	if chunk != c.currChunk {
+		// flush out the previous chunk details
+		err := c.flushContents()
+		if err != nil {
+			return err
+		}
+		// clearing the chunk specific meta for next chunk
+		c.chunkBuf.Reset()
+		c.chunkMetaBuf.Reset()
+		c.chunkMeta = c.chunkMeta[:0]
+		c.currChunk = chunk
+	}
+
+	// get the starting offset for this doc
+	dvOffset := c.chunkBuf.Len()
+	dvSize, err := c.chunkBuf.Write(vals)
+	if err != nil {
+		return err
+	}
+
+	c.chunkMeta = append(c.chunkMeta, MetaData{
+		DocNum:      docNum,
+		DocDvOffset: uint64(dvOffset + dvSize),
+	})
+	return nil
+}
+
+// Write commits all the encoded chunked contents to the provided writer.
+//
+// | ..... data ..... | chunk offsets (varints)
+// | position of chunk offsets (uint64) | number of offsets (uint64) |
+//
+func (c *chunkedContentCoder) Write() (int, error) {
+	var tw int
+
+	if c.final != nil {
+		// write out the data section first
+		nw, err := c.w.Write(c.final)
+		tw += nw
+		if err != nil {
+			return tw, err
+		}
+	}
+
+	chunkOffsetsStart := uint64(tw)
+
+	if cap(c.final) < binary.MaxVarintLen64 {
+		c.final = make([]byte, binary.MaxVarintLen64)
+	} else {
+		c.final = c.final[0:binary.MaxVarintLen64]
+	}
+	chunkOffsets := modifyLengthsToEndOffsets(c.chunkLens)
+	// write out the chunk offsets
+	for _, chunkOffset := range chunkOffsets {
+		n := binary.PutUvarint(c.final, chunkOffset)
+		nw, err := c.w.Write(c.final[:n])
+		tw += nw
+		if err != nil {
+			return tw, err
+		}
+	}
+
+	chunkOffsetsLen := uint64(tw) - chunkOffsetsStart
+
+	c.final = c.final[0:8]
+	// write out the length of chunk offsets
+	binary.BigEndian.PutUint64(c.final, chunkOffsetsLen)
+	nw, err := c.w.Write(c.final)
+	tw += nw
+	if err != nil {
+		return tw, err
+	}
+
+	// write out the number of chunks
+	binary.BigEndian.PutUint64(c.final, uint64(len(c.chunkLens)))
+	nw, err = c.w.Write(c.final)
+	tw += nw
+	if err != nil {
+		return tw, err
+	}
+
+	c.final = c.final[:0]
+
+	return tw, nil
+}
+
+// ReadDocValueBoundary elicits the start, end offsets from a
+// metaData header slice
+func ReadDocValueBoundary(chunk int, metaHeaders []MetaData) (uint64, uint64) {
+	var start uint64
+	if chunk > 0 {
+		start = metaHeaders[chunk-1].DocDvOffset
+	}
+	return start, metaHeaders[chunk].DocDvOffset
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/count.go b/vendor/github.com/blevesearch/zap/v12/count.go
new file mode 100644
index 0000000000..50290f8882
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/count.go
@@ -0,0 +1,61 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"hash/crc32"
+	"io"
+
+	"github.com/blevesearch/bleve/index/scorch/segment"
+)
+
+// CountHashWriter is a wrapper around a Writer which counts the number of
+// bytes which have been written and computes a crc32 hash
+type CountHashWriter struct {
+	w   io.Writer
+	crc uint32
+	n   int
+	s   segment.StatsReporter
+}
+
+// NewCountHashWriter returns a CountHashWriter which wraps the provided Writer
+func NewCountHashWriter(w io.Writer) *CountHashWriter {
+	return &CountHashWriter{w: w}
+}
+
+func NewCountHashWriterWithStatsReporter(w io.Writer, s segment.StatsReporter) *CountHashWriter {
+	return &CountHashWriter{w: w, s: s}
+}
+
+// Write writes the provided bytes to the wrapped writer and counts the bytes
+func (c *CountHashWriter) Write(b []byte) (int, error) {
+	n, err := c.w.Write(b)
+	c.crc = crc32.Update(c.crc, crc32.IEEETable, b[:n])
+	c.n += n
+	if c.s != nil {
+		c.s.ReportBytesWritten(uint64(n))
+	}
+	return n, err
+}
+
+// Count returns the number of bytes written
+func (c *CountHashWriter) Count() int {
+	return c.n
+}
+
+// Sum32 returns the CRC-32 hash of the content written to this writer
+func (c *CountHashWriter) Sum32() uint32 {
+	return c.crc
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/dict.go b/vendor/github.com/blevesearch/zap/v12/dict.go
new file mode 100644
index 0000000000..ad4a8f8dc5
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/dict.go
@@ -0,0 +1,263 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"fmt"
+
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/couchbase/vellum"
+)
+
+// Dictionary is the zap representation of the term dictionary
+type Dictionary struct {
+	sb        *SegmentBase
+	field     string
+	fieldID   uint16
+	fst       *vellum.FST
+	fstReader *vellum.Reader
+}
+
+// PostingsList returns the postings list for the specified term
+func (d *Dictionary) PostingsList(term []byte, except *roaring.Bitmap,
+	prealloc segment.PostingsList) (segment.PostingsList, error) {
+	var preallocPL *PostingsList
+	pl, ok := prealloc.(*PostingsList)
+	if ok && pl != nil {
+		preallocPL = pl
+	}
+	return d.postingsList(term, except, preallocPL)
+}
+
+func (d *Dictionary) postingsList(term []byte, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
+	if d.fstReader == nil {
+		if rv == nil || rv == emptyPostingsList {
+			return emptyPostingsList, nil
+		}
+		return d.postingsListInit(rv, except), nil
+	}
+
+	postingsOffset, exists, err := d.fstReader.Get(term)
+	if err != nil {
+		return nil, fmt.Errorf("vellum err: %v", err)
+	}
+	if !exists {
+		if rv == nil || rv == emptyPostingsList {
+			return emptyPostingsList, nil
+		}
+		return d.postingsListInit(rv, except), nil
+	}
+
+	return d.postingsListFromOffset(postingsOffset, except, rv)
+}
+
+func (d *Dictionary) postingsListFromOffset(postingsOffset uint64, except *roaring.Bitmap, rv *PostingsList) (*PostingsList, error) {
+	rv = d.postingsListInit(rv, except)
+
+	err := rv.read(postingsOffset, d)
+	if err != nil {
+		return nil, err
+	}
+
+	return rv, nil
+}
+
+func (d *Dictionary) postingsListInit(rv *PostingsList, except *roaring.Bitmap) *PostingsList {
+	if rv == nil || rv == emptyPostingsList {
+		rv = &PostingsList{}
+	} else {
+		postings := rv.postings
+		if postings != nil {
+			postings.Clear()
+		}
+
+		*rv = PostingsList{} // clear the struct
+
+		rv.postings = postings
+	}
+	rv.sb = d.sb
+	rv.except = except
+	return rv
+}
+
+func (d *Dictionary) Contains(key []byte) (bool, error) {
+	return d.fst.Contains(key)
+}
+
+// Iterator returns an iterator for this dictionary
+func (d *Dictionary) Iterator() segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator(nil, nil)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// PrefixIterator returns an iterator which only visits terms having the
+// the specified prefix
+func (d *Dictionary) PrefixIterator(prefix string) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	kBeg := []byte(prefix)
+	kEnd := segment.IncrementBytes(kBeg)
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator(kBeg, kEnd)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// RangeIterator returns an iterator which only visits terms between the
+// start and end terms.  NOTE: bleve.index API specifies the end is inclusive.
+func (d *Dictionary) RangeIterator(start, end string) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	// need to increment the end position to be inclusive
+	var endBytes []byte
+	if len(end) > 0 {
+		endBytes = []byte(end)
+		if endBytes[len(endBytes)-1] < 0xff {
+			endBytes[len(endBytes)-1]++
+		} else {
+			endBytes = append(endBytes, 0xff)
+		}
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Iterator([]byte(start), endBytes)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+// AutomatonIterator returns an iterator which only visits terms
+// having the the vellum automaton and start/end key range
+func (d *Dictionary) AutomatonIterator(a vellum.Automaton,
+	startKeyInclusive, endKeyExclusive []byte) segment.DictionaryIterator {
+	rv := &DictionaryIterator{
+		d: d,
+	}
+
+	if d.fst != nil {
+		itr, err := d.fst.Search(a, startKeyInclusive, endKeyExclusive)
+		if err == nil {
+			rv.itr = itr
+		} else if err != vellum.ErrIteratorDone {
+			rv.err = err
+		}
+	}
+
+	return rv
+}
+
+func (d *Dictionary) OnlyIterator(onlyTerms [][]byte,
+	includeCount bool) segment.DictionaryIterator {
+
+	rv := &DictionaryIterator{
+		d:         d,
+		omitCount: !includeCount,
+	}
+
+	var buf bytes.Buffer
+	builder, err := vellum.New(&buf, nil)
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+	for _, term := range onlyTerms {
+		err = builder.Insert(term, 0)
+		if err != nil {
+			rv.err = err
+			return rv
+		}
+	}
+	err = builder.Close()
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+
+	onlyFST, err := vellum.Load(buf.Bytes())
+	if err != nil {
+		rv.err = err
+		return rv
+	}
+
+	itr, err := d.fst.Search(onlyFST, nil, nil)
+	if err == nil {
+		rv.itr = itr
+	} else if err != vellum.ErrIteratorDone {
+		rv.err = err
+	}
+
+	return rv
+}
+
+// DictionaryIterator is an iterator for term dictionary
+type DictionaryIterator struct {
+	d         *Dictionary
+	itr       vellum.Iterator
+	err       error
+	tmp       PostingsList
+	entry     index.DictEntry
+	omitCount bool
+}
+
+// Next returns the next entry in the dictionary
+func (i *DictionaryIterator) Next() (*index.DictEntry, error) {
+	if i.err != nil && i.err != vellum.ErrIteratorDone {
+		return nil, i.err
+	} else if i.itr == nil || i.err == vellum.ErrIteratorDone {
+		return nil, nil
+	}
+	term, postingsOffset := i.itr.Current()
+	i.entry.Term = string(term)
+	if !i.omitCount {
+		i.err = i.tmp.read(postingsOffset, i.d)
+		if i.err != nil {
+			return nil, i.err
+		}
+		i.entry.Count = i.tmp.Count()
+	}
+	i.err = i.itr.Next()
+	return &i.entry, nil
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/docvalues.go b/vendor/github.com/blevesearch/zap/v12/docvalues.go
new file mode 100644
index 0000000000..793797bd8a
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/docvalues.go
@@ -0,0 +1,312 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"math"
+	"reflect"
+	"sort"
+
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/blevesearch/bleve/size"
+	"github.com/golang/snappy"
+)
+
+var reflectStaticSizedocValueReader int
+
+func init() {
+	var dvi docValueReader
+	reflectStaticSizedocValueReader = int(reflect.TypeOf(dvi).Size())
+}
+
+type docNumTermsVisitor func(docNum uint64, terms []byte) error
+
+type docVisitState struct {
+	dvrs    map[uint16]*docValueReader
+	segment *SegmentBase
+}
+
+type docValueReader struct {
+	field          string
+	curChunkNum    uint64
+	chunkOffsets   []uint64
+	dvDataLoc      uint64
+	curChunkHeader []MetaData
+	curChunkData   []byte // compressed data cache
+	uncompressed   []byte // temp buf for snappy decompression
+}
+
+func (di *docValueReader) size() int {
+	return reflectStaticSizedocValueReader + size.SizeOfPtr +
+		len(di.field) +
+		len(di.chunkOffsets)*size.SizeOfUint64 +
+		len(di.curChunkHeader)*reflectStaticSizeMetaData +
+		len(di.curChunkData)
+}
+
+func (di *docValueReader) cloneInto(rv *docValueReader) *docValueReader {
+	if rv == nil {
+		rv = &docValueReader{}
+	}
+
+	rv.field = di.field
+	rv.curChunkNum = math.MaxUint64
+	rv.chunkOffsets = di.chunkOffsets // immutable, so it's sharable
+	rv.dvDataLoc = di.dvDataLoc
+	rv.curChunkHeader = rv.curChunkHeader[:0]
+	rv.curChunkData = nil
+	rv.uncompressed = rv.uncompressed[:0]
+
+	return rv
+}
+
+func (di *docValueReader) curChunkNumber() uint64 {
+	return di.curChunkNum
+}
+
+func (s *SegmentBase) loadFieldDocValueReader(field string,
+	fieldDvLocStart, fieldDvLocEnd uint64) (*docValueReader, error) {
+	// get the docValue offset for the given fields
+	if fieldDvLocStart == fieldNotUninverted {
+		// no docValues found, nothing to do
+		return nil, nil
+	}
+
+	// read the number of chunks, and chunk offsets position
+	var numChunks, chunkOffsetsPosition uint64
+
+	if fieldDvLocEnd-fieldDvLocStart > 16 {
+		numChunks = binary.BigEndian.Uint64(s.mem[fieldDvLocEnd-8 : fieldDvLocEnd])
+		// read the length of chunk offsets
+		chunkOffsetsLen := binary.BigEndian.Uint64(s.mem[fieldDvLocEnd-16 : fieldDvLocEnd-8])
+		// acquire position of chunk offsets
+		chunkOffsetsPosition = (fieldDvLocEnd - 16) - chunkOffsetsLen
+	} else {
+		return nil, fmt.Errorf("loadFieldDocValueReader: fieldDvLoc too small: %d-%d", fieldDvLocEnd, fieldDvLocStart)
+	}
+
+	fdvIter := &docValueReader{
+		curChunkNum:  math.MaxUint64,
+		field:        field,
+		chunkOffsets: make([]uint64, int(numChunks)),
+	}
+
+	// read the chunk offsets
+	var offset uint64
+	for i := 0; i < int(numChunks); i++ {
+		loc, read := binary.Uvarint(s.mem[chunkOffsetsPosition+offset : chunkOffsetsPosition+offset+binary.MaxVarintLen64])
+		if read <= 0 {
+			return nil, fmt.Errorf("corrupted chunk offset during segment load")
+		}
+		fdvIter.chunkOffsets[i] = loc
+		offset += uint64(read)
+	}
+
+	// set the data offset
+	fdvIter.dvDataLoc = fieldDvLocStart
+
+	return fdvIter, nil
+}
+
+func (di *docValueReader) loadDvChunk(chunkNumber uint64, s *SegmentBase) error {
+	// advance to the chunk where the docValues
+	// reside for the given docNum
+	destChunkDataLoc, curChunkEnd := di.dvDataLoc, di.dvDataLoc
+	start, end := readChunkBoundary(int(chunkNumber), di.chunkOffsets)
+	if start >= end {
+		di.curChunkHeader = di.curChunkHeader[:0]
+		di.curChunkData = nil
+		di.curChunkNum = chunkNumber
+		di.uncompressed = di.uncompressed[:0]
+		return nil
+	}
+
+	destChunkDataLoc += start
+	curChunkEnd += end
+
+	// read the number of docs reside in the chunk
+	numDocs, read := binary.Uvarint(s.mem[destChunkDataLoc : destChunkDataLoc+binary.MaxVarintLen64])
+	if read <= 0 {
+		return fmt.Errorf("failed to read the chunk")
+	}
+	chunkMetaLoc := destChunkDataLoc + uint64(read)
+
+	offset := uint64(0)
+	if cap(di.curChunkHeader) < int(numDocs) {
+		di.curChunkHeader = make([]MetaData, int(numDocs))
+	} else {
+		di.curChunkHeader = di.curChunkHeader[:int(numDocs)]
+	}
+	for i := 0; i < int(numDocs); i++ {
+		di.curChunkHeader[i].DocNum, read = binary.Uvarint(s.mem[chunkMetaLoc+offset : chunkMetaLoc+offset+binary.MaxVarintLen64])
+		offset += uint64(read)
+		di.curChunkHeader[i].DocDvOffset, read = binary.Uvarint(s.mem[chunkMetaLoc+offset : chunkMetaLoc+offset+binary.MaxVarintLen64])
+		offset += uint64(read)
+	}
+
+	compressedDataLoc := chunkMetaLoc + offset
+	dataLength := curChunkEnd - compressedDataLoc
+	di.curChunkData = s.mem[compressedDataLoc : compressedDataLoc+dataLength]
+	di.curChunkNum = chunkNumber
+	di.uncompressed = di.uncompressed[:0]
+	return nil
+}
+
+func (di *docValueReader) iterateAllDocValues(s *SegmentBase, visitor docNumTermsVisitor) error {
+	for i := 0; i < len(di.chunkOffsets); i++ {
+		err := di.loadDvChunk(uint64(i), s)
+		if err != nil {
+			return err
+		}
+		if di.curChunkData == nil || len(di.curChunkHeader) == 0 {
+			continue
+		}
+
+		// uncompress the already loaded data
+		uncompressed, err := snappy.Decode(di.uncompressed[:cap(di.uncompressed)], di.curChunkData)
+		if err != nil {
+			return err
+		}
+		di.uncompressed = uncompressed
+
+		start := uint64(0)
+		for _, entry := range di.curChunkHeader {
+			err = visitor(entry.DocNum, uncompressed[start:entry.DocDvOffset])
+			if err != nil {
+				return err
+			}
+
+			start = entry.DocDvOffset
+		}
+	}
+
+	return nil
+}
+
+func (di *docValueReader) visitDocValues(docNum uint64,
+	visitor index.DocumentFieldTermVisitor) error {
+	// binary search the term locations for the docNum
+	start, end := di.getDocValueLocs(docNum)
+	if start == math.MaxUint64 || end == math.MaxUint64 || start == end {
+		return nil
+	}
+
+	var uncompressed []byte
+	var err error
+	// use the uncompressed copy if available
+	if len(di.uncompressed) > 0 {
+		uncompressed = di.uncompressed
+	} else {
+		// uncompress the already loaded data
+		uncompressed, err = snappy.Decode(di.uncompressed[:cap(di.uncompressed)], di.curChunkData)
+		if err != nil {
+			return err
+		}
+		di.uncompressed = uncompressed
+	}
+
+	// pick the terms for the given docNum
+	uncompressed = uncompressed[start:end]
+	for {
+		i := bytes.Index(uncompressed, termSeparatorSplitSlice)
+		if i < 0 {
+			break
+		}
+
+		visitor(di.field, uncompressed[0:i])
+		uncompressed = uncompressed[i+1:]
+	}
+
+	return nil
+}
+
+func (di *docValueReader) getDocValueLocs(docNum uint64) (uint64, uint64) {
+	i := sort.Search(len(di.curChunkHeader), func(i int) bool {
+		return di.curChunkHeader[i].DocNum >= docNum
+	})
+	if i < len(di.curChunkHeader) && di.curChunkHeader[i].DocNum == docNum {
+		return ReadDocValueBoundary(i, di.curChunkHeader)
+	}
+	return math.MaxUint64, math.MaxUint64
+}
+
+// VisitDocumentFieldTerms is an implementation of the
+// DocumentFieldTermVisitable interface
+func (s *SegmentBase) VisitDocumentFieldTerms(localDocNum uint64, fields []string,
+	visitor index.DocumentFieldTermVisitor, dvsIn segment.DocVisitState) (
+	segment.DocVisitState, error) {
+	dvs, ok := dvsIn.(*docVisitState)
+	if !ok || dvs == nil {
+		dvs = &docVisitState{}
+	} else {
+		if dvs.segment != s {
+			dvs.segment = s
+			dvs.dvrs = nil
+		}
+	}
+
+	var fieldIDPlus1 uint16
+	if dvs.dvrs == nil {
+		dvs.dvrs = make(map[uint16]*docValueReader, len(fields))
+		for _, field := range fields {
+			if fieldIDPlus1, ok = s.fieldsMap[field]; !ok {
+				continue
+			}
+			fieldID := fieldIDPlus1 - 1
+			if dvIter, exists := s.fieldDvReaders[fieldID]; exists &&
+				dvIter != nil {
+				dvs.dvrs[fieldID] = dvIter.cloneInto(dvs.dvrs[fieldID])
+			}
+		}
+	}
+
+	// find the chunkNumber where the docValues are stored
+	// NOTE: doc values continue to use legacy chunk mode
+	chunkFactor, err := getChunkSize(LegacyChunkMode, 0, 0)
+	if err != nil {
+		return nil, err
+	}
+	docInChunk := localDocNum / chunkFactor
+	var dvr *docValueReader
+	for _, field := range fields {
+		if fieldIDPlus1, ok = s.fieldsMap[field]; !ok {
+			continue
+		}
+		fieldID := fieldIDPlus1 - 1
+		if dvr, ok = dvs.dvrs[fieldID]; ok && dvr != nil {
+			// check if the chunk is already loaded
+			if docInChunk != dvr.curChunkNumber() {
+				err := dvr.loadDvChunk(docInChunk, s)
+				if err != nil {
+					return dvs, err
+				}
+			}
+
+			_ = dvr.visitDocValues(localDocNum, visitor)
+		}
+	}
+	return dvs, nil
+}
+
+// VisitableDocValueFields returns the list of fields with
+// persisted doc value terms ready to be visitable using the
+// VisitDocumentFieldTerms method.
+func (s *SegmentBase) VisitableDocValueFields() ([]string, error) {
+	return s.fieldDvNames, nil
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/enumerator.go b/vendor/github.com/blevesearch/zap/v12/enumerator.go
new file mode 100644
index 0000000000..bc5b7e6276
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/enumerator.go
@@ -0,0 +1,138 @@
+//  Copyright (c) 2018 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+
+	"github.com/couchbase/vellum"
+)
+
+// enumerator provides an ordered traversal of multiple vellum
+// iterators.  Like JOIN of iterators, the enumerator produces a
+// sequence of (key, iteratorIndex, value) tuples, sorted by key ASC,
+// then iteratorIndex ASC, where the same key might be seen or
+// repeated across multiple child iterators.
+type enumerator struct {
+	itrs   []vellum.Iterator
+	currKs [][]byte
+	currVs []uint64
+
+	lowK    []byte
+	lowIdxs []int
+	lowCurr int
+}
+
+// newEnumerator returns a new enumerator over the vellum Iterators
+func newEnumerator(itrs []vellum.Iterator) (*enumerator, error) {
+	rv := &enumerator{
+		itrs:    itrs,
+		currKs:  make([][]byte, len(itrs)),
+		currVs:  make([]uint64, len(itrs)),
+		lowIdxs: make([]int, 0, len(itrs)),
+	}
+	for i, itr := range rv.itrs {
+		rv.currKs[i], rv.currVs[i] = itr.Current()
+	}
+	rv.updateMatches(false)
+	if rv.lowK == nil && len(rv.lowIdxs) == 0 {
+		return rv, vellum.ErrIteratorDone
+	}
+	return rv, nil
+}
+
+// updateMatches maintains the low key matches based on the currKs
+func (m *enumerator) updateMatches(skipEmptyKey bool) {
+	m.lowK = nil
+	m.lowIdxs = m.lowIdxs[:0]
+	m.lowCurr = 0
+
+	for i, key := range m.currKs {
+		if (key == nil && m.currVs[i] == 0) || // in case of empty iterator
+			(len(key) == 0 && skipEmptyKey) { // skip empty keys
+			continue
+		}
+
+		cmp := bytes.Compare(key, m.lowK)
+		if cmp < 0 || len(m.lowIdxs) == 0 {
+			// reached a new low
+			m.lowK = key
+			m.lowIdxs = m.lowIdxs[:0]
+			m.lowIdxs = append(m.lowIdxs, i)
+		} else if cmp == 0 {
+			m.lowIdxs = append(m.lowIdxs, i)
+		}
+	}
+}
+
+// Current returns the enumerator's current key, iterator-index, and
+// value.  If the enumerator is not pointing at a valid value (because
+// Next returned an error previously), Current will return nil,0,0.
+func (m *enumerator) Current() ([]byte, int, uint64) {
+	var i int
+	var v uint64
+	if m.lowCurr < len(m.lowIdxs) {
+		i = m.lowIdxs[m.lowCurr]
+		v = m.currVs[i]
+	}
+	return m.lowK, i, v
+}
+
+// GetLowIdxsAndValues will return all of the iterator indices
+// which point to the current key, and their corresponding
+// values.  This can be used by advanced caller which may need
+// to peek into these other sets of data before processing.
+func (m *enumerator) GetLowIdxsAndValues() ([]int, []uint64) {
+	values := make([]uint64, 0, len(m.lowIdxs))
+	for _, idx := range m.lowIdxs {
+		values = append(values, m.currVs[idx])
+	}
+	return m.lowIdxs, values
+}
+
+// Next advances the enumerator to the next key/iterator/value result,
+// else vellum.ErrIteratorDone is returned.
+func (m *enumerator) Next() error {
+	m.lowCurr += 1
+	if m.lowCurr >= len(m.lowIdxs) {
+		// move all the current low iterators forwards
+		for _, vi := range m.lowIdxs {
+			err := m.itrs[vi].Next()
+			if err != nil && err != vellum.ErrIteratorDone {
+				return err
+			}
+			m.currKs[vi], m.currVs[vi] = m.itrs[vi].Current()
+		}
+		// can skip any empty keys encountered at this point
+		m.updateMatches(true)
+	}
+	if m.lowK == nil && len(m.lowIdxs) == 0 {
+		return vellum.ErrIteratorDone
+	}
+	return nil
+}
+
+// Close all the underlying Iterators.  The first error, if any, will
+// be returned.
+func (m *enumerator) Close() error {
+	var rv error
+	for _, itr := range m.itrs {
+		err := itr.Close()
+		if rv == nil {
+			rv = err
+		}
+	}
+	return rv
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/go.mod b/vendor/github.com/blevesearch/zap/v12/go.mod
new file mode 100644
index 0000000000..24bbcb2c16
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/go.mod
@@ -0,0 +1,12 @@
+module github.com/blevesearch/zap/v12
+
+go 1.12
+
+require (
+	github.com/RoaringBitmap/roaring v0.4.21
+	github.com/blevesearch/bleve v1.0.7
+	github.com/blevesearch/mmap-go v1.0.2
+	github.com/couchbase/vellum v1.0.1
+	github.com/golang/snappy v0.0.1
+	github.com/spf13/cobra v0.0.5
+)
diff --git a/vendor/github.com/blevesearch/zap/v12/intDecoder.go b/vendor/github.com/blevesearch/zap/v12/intDecoder.go
new file mode 100644
index 0000000000..4cd008ff26
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/intDecoder.go
@@ -0,0 +1,111 @@
+//  Copyright (c) 2019 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"encoding/binary"
+	"fmt"
+
+	"github.com/blevesearch/bleve/index/scorch/segment"
+)
+
+type chunkedIntDecoder struct {
+	startOffset     uint64
+	dataStartOffset uint64
+	chunkOffsets    []uint64
+	curChunkBytes   []byte
+	data            []byte
+	r               *segment.MemUvarintReader
+}
+
+func newChunkedIntDecoder(buf []byte, offset uint64) *chunkedIntDecoder {
+	rv := &chunkedIntDecoder{startOffset: offset, data: buf}
+	var n, numChunks uint64
+	var read int
+	if offset == termNotEncoded {
+		numChunks = 0
+	} else {
+		numChunks, read = binary.Uvarint(buf[offset+n : offset+n+binary.MaxVarintLen64])
+	}
+
+	n += uint64(read)
+	if cap(rv.chunkOffsets) >= int(numChunks) {
+		rv.chunkOffsets = rv.chunkOffsets[:int(numChunks)]
+	} else {
+		rv.chunkOffsets = make([]uint64, int(numChunks))
+	}
+	for i := 0; i < int(numChunks); i++ {
+		rv.chunkOffsets[i], read = binary.Uvarint(buf[offset+n : offset+n+binary.MaxVarintLen64])
+		n += uint64(read)
+	}
+	rv.dataStartOffset = offset + n
+	return rv
+}
+
+func (d *chunkedIntDecoder) loadChunk(chunk int) error {
+	if d.startOffset == termNotEncoded {
+		d.r = segment.NewMemUvarintReader([]byte(nil))
+		return nil
+	}
+
+	if chunk >= len(d.chunkOffsets) {
+		return fmt.Errorf("tried to load freq chunk that doesn't exist %d/(%d)",
+			chunk, len(d.chunkOffsets))
+	}
+
+	end, start := d.dataStartOffset, d.dataStartOffset
+	s, e := readChunkBoundary(chunk, d.chunkOffsets)
+	start += s
+	end += e
+	d.curChunkBytes = d.data[start:end]
+	if d.r == nil {
+		d.r = segment.NewMemUvarintReader(d.curChunkBytes)
+	} else {
+		d.r.Reset(d.curChunkBytes)
+	}
+
+	return nil
+}
+
+func (d *chunkedIntDecoder) reset() {
+	d.startOffset = 0
+	d.dataStartOffset = 0
+	d.chunkOffsets = d.chunkOffsets[:0]
+	d.curChunkBytes = d.curChunkBytes[:0]
+	d.data = d.data[:0]
+	if d.r != nil {
+		d.r.Reset([]byte(nil))
+	}
+}
+
+func (d *chunkedIntDecoder) isNil() bool {
+	return d.curChunkBytes == nil
+}
+
+func (d *chunkedIntDecoder) readUvarint() (uint64, error) {
+	return d.r.ReadUvarint()
+}
+
+func (d *chunkedIntDecoder) SkipUvarint() {
+	d.r.SkipUvarint()
+}
+
+func (d *chunkedIntDecoder) SkipBytes(count int) {
+	d.r.SkipBytes(count)
+}
+
+func (d *chunkedIntDecoder) Len() int {
+	return d.r.Len()
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/intcoder.go b/vendor/github.com/blevesearch/zap/v12/intcoder.go
new file mode 100644
index 0000000000..7682593e9f
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/intcoder.go
@@ -0,0 +1,203 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"encoding/binary"
+	"io"
+	"math"
+)
+
+const termNotEncoded = math.MaxUint64
+
+type chunkedIntCoder struct {
+	final     []byte
+	chunkSize uint64
+	chunkBuf  bytes.Buffer
+	chunkLens []uint64
+	currChunk uint64
+
+	buf []byte
+}
+
+// newChunkedIntCoder returns a new chunk int coder which packs data into
+// chunks based on the provided chunkSize and supports up to the specified
+// maxDocNum
+func newChunkedIntCoder(chunkSize uint64, maxDocNum uint64) *chunkedIntCoder {
+	total := maxDocNum/chunkSize + 1
+	rv := &chunkedIntCoder{
+		chunkSize: chunkSize,
+		chunkLens: make([]uint64, total),
+		final:     make([]byte, 0, 64),
+	}
+
+	return rv
+}
+
+// Reset lets you reuse this chunked int coder.  buffers are reset and reused
+// from previous use.  you cannot change the chunk size or max doc num.
+func (c *chunkedIntCoder) Reset() {
+	c.final = c.final[:0]
+	c.chunkBuf.Reset()
+	c.currChunk = 0
+	for i := range c.chunkLens {
+		c.chunkLens[i] = 0
+	}
+}
+
+// SetChunkSize changes the chunk size.  It is only valid to do so
+// with a new chunkedIntCoder, or immediately after calling Reset()
+func (c *chunkedIntCoder) SetChunkSize(chunkSize uint64, maxDocNum uint64) {
+	total := int(maxDocNum/chunkSize + 1)
+	c.chunkSize = chunkSize
+	if cap(c.chunkLens) < total {
+		c.chunkLens = make([]uint64, total)
+	} else {
+		c.chunkLens = c.chunkLens[:total]
+	}
+}
+
+// Add encodes the provided integers into the correct chunk for the provided
+// doc num.  You MUST call Add() with increasing docNums.
+func (c *chunkedIntCoder) Add(docNum uint64, vals ...uint64) error {
+	chunk := docNum / c.chunkSize
+	if chunk != c.currChunk {
+		// starting a new chunk
+		c.Close()
+		c.chunkBuf.Reset()
+		c.currChunk = chunk
+	}
+
+	if len(c.buf) < binary.MaxVarintLen64 {
+		c.buf = make([]byte, binary.MaxVarintLen64)
+	}
+
+	for _, val := range vals {
+		wb := binary.PutUvarint(c.buf, val)
+		_, err := c.chunkBuf.Write(c.buf[:wb])
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (c *chunkedIntCoder) AddBytes(docNum uint64, buf []byte) error {
+	chunk := docNum / c.chunkSize
+	if chunk != c.currChunk {
+		// starting a new chunk
+		c.Close()
+		c.chunkBuf.Reset()
+		c.currChunk = chunk
+	}
+
+	_, err := c.chunkBuf.Write(buf)
+	return err
+}
+
+// Close indicates you are done calling Add() this allows the final chunk
+// to be encoded.
+func (c *chunkedIntCoder) Close() {
+	encodingBytes := c.chunkBuf.Bytes()
+	c.chunkLens[c.currChunk] = uint64(len(encodingBytes))
+	c.final = append(c.final, encodingBytes...)
+	c.currChunk = uint64(cap(c.chunkLens)) // sentinel to detect double close
+}
+
+// Write commits all the encoded chunked integers to the provided writer.
+func (c *chunkedIntCoder) Write(w io.Writer) (int, error) {
+	bufNeeded := binary.MaxVarintLen64 * (1 + len(c.chunkLens))
+	if len(c.buf) < bufNeeded {
+		c.buf = make([]byte, bufNeeded)
+	}
+	buf := c.buf
+
+	// convert the chunk lengths into chunk offsets
+	chunkOffsets := modifyLengthsToEndOffsets(c.chunkLens)
+
+	// write out the number of chunks & each chunk offsets
+	n := binary.PutUvarint(buf, uint64(len(chunkOffsets)))
+	for _, chunkOffset := range chunkOffsets {
+		n += binary.PutUvarint(buf[n:], chunkOffset)
+	}
+
+	tw, err := w.Write(buf[:n])
+	if err != nil {
+		return tw, err
+	}
+
+	// write out the data
+	nw, err := w.Write(c.final)
+	tw += nw
+	if err != nil {
+		return tw, err
+	}
+	return tw, nil
+}
+
+// writeAt commits all the encoded chunked integers to the provided writer
+// and returns the starting offset, total bytes written and an error
+func (c *chunkedIntCoder) writeAt(w io.Writer) (uint64, int, error) {
+	startOffset := uint64(termNotEncoded)
+	if len(c.final) <= 0 {
+		return startOffset, 0, nil
+	}
+
+	if chw := w.(*CountHashWriter); chw != nil {
+		startOffset = uint64(chw.Count())
+	}
+
+	tw, err := c.Write(w)
+	return startOffset, tw, err
+}
+
+func (c *chunkedIntCoder) FinalSize() int {
+	return len(c.final)
+}
+
+// modifyLengthsToEndOffsets converts the chunk length array
+// to a chunk offset array. The readChunkBoundary
+// will figure out the start and end of every chunk from
+// these offsets. Starting offset of i'th index is stored
+// in i-1'th position except for 0'th index and ending offset
+// is stored at i'th index position.
+// For 0'th element, starting position is always zero.
+// eg:
+// Lens ->  5 5 5 5 => 5 10 15 20
+// Lens ->  0 5 0 5 => 0 5 5 10
+// Lens ->  0 0 0 5 => 0 0 0 5
+// Lens ->  5 0 0 0 => 5 5 5 5
+// Lens ->  0 5 0 0 => 0 5 5 5
+// Lens ->  0 0 5 0 => 0 0 5 5
+func modifyLengthsToEndOffsets(lengths []uint64) []uint64 {
+	var runningOffset uint64
+	var index, i int
+	for i = 1; i <= len(lengths); i++ {
+		runningOffset += lengths[i-1]
+		lengths[index] = runningOffset
+		index++
+	}
+	return lengths
+}
+
+func readChunkBoundary(chunk int, offsets []uint64) (uint64, uint64) {
+	var start uint64
+	if chunk > 0 {
+		start = offsets[chunk-1]
+	}
+	return start, offsets[chunk]
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/merge.go b/vendor/github.com/blevesearch/zap/v12/merge.go
new file mode 100644
index 0000000000..805100fb5f
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/merge.go
@@ -0,0 +1,847 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"math"
+	"os"
+	"sort"
+
+	"github.com/RoaringBitmap/roaring"
+	seg "github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/couchbase/vellum"
+	"github.com/golang/snappy"
+)
+
+var DefaultFileMergerBufferSize = 1024 * 1024
+
+const docDropped = math.MaxUint64 // sentinel docNum to represent a deleted doc
+
+// Merge takes a slice of segments and bit masks describing which
+// documents may be dropped, and creates a new segment containing the
+// remaining data.  This new segment is built at the specified path.
+func (*ZapPlugin) Merge(segments []seg.Segment, drops []*roaring.Bitmap, path string,
+	closeCh chan struct{}, s seg.StatsReporter) (
+	[][]uint64, uint64, error) {
+
+	segmentBases := make([]*SegmentBase, len(segments))
+	for segmenti, segment := range segments {
+		switch segmentx := segment.(type) {
+		case *Segment:
+			segmentBases[segmenti] = &segmentx.SegmentBase
+		case *SegmentBase:
+			segmentBases[segmenti] = segmentx
+		default:
+			panic(fmt.Sprintf("oops, unexpected segment type: %T", segment))
+		}
+	}
+	return mergeSegmentBases(segmentBases, drops, path, DefaultChunkMode, closeCh, s)
+}
+
+func mergeSegmentBases(segmentBases []*SegmentBase, drops []*roaring.Bitmap, path string,
+	chunkMode uint32, closeCh chan struct{}, s seg.StatsReporter) (
+	[][]uint64, uint64, error) {
+	flag := os.O_RDWR | os.O_CREATE
+
+	f, err := os.OpenFile(path, flag, 0600)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	cleanup := func() {
+		_ = f.Close()
+		_ = os.Remove(path)
+	}
+
+	// buffer the output
+	br := bufio.NewWriterSize(f, DefaultFileMergerBufferSize)
+
+	// wrap it for counting (tracking offsets)
+	cr := NewCountHashWriterWithStatsReporter(br, s)
+
+	newDocNums, numDocs, storedIndexOffset, fieldsIndexOffset, docValueOffset, _, _, _, err :=
+		MergeToWriter(segmentBases, drops, chunkMode, cr, closeCh)
+	if err != nil {
+		cleanup()
+		return nil, 0, err
+	}
+
+	err = persistFooter(numDocs, storedIndexOffset, fieldsIndexOffset,
+		docValueOffset, chunkMode, cr.Sum32(), cr)
+	if err != nil {
+		cleanup()
+		return nil, 0, err
+	}
+
+	err = br.Flush()
+	if err != nil {
+		cleanup()
+		return nil, 0, err
+	}
+
+	err = f.Sync()
+	if err != nil {
+		cleanup()
+		return nil, 0, err
+	}
+
+	err = f.Close()
+	if err != nil {
+		cleanup()
+		return nil, 0, err
+	}
+
+	return newDocNums, uint64(cr.Count()), nil
+}
+
+func MergeToWriter(segments []*SegmentBase, drops []*roaring.Bitmap,
+	chunkMode uint32, cr *CountHashWriter, closeCh chan struct{}) (
+	newDocNums [][]uint64,
+	numDocs, storedIndexOffset, fieldsIndexOffset, docValueOffset uint64,
+	dictLocs []uint64, fieldsInv []string, fieldsMap map[string]uint16,
+	err error) {
+	docValueOffset = uint64(fieldNotUninverted)
+
+	var fieldsSame bool
+	fieldsSame, fieldsInv = mergeFields(segments)
+	fieldsMap = mapFields(fieldsInv)
+
+	numDocs = computeNewDocCount(segments, drops)
+
+	if isClosed(closeCh) {
+		return nil, 0, 0, 0, 0, nil, nil, nil, seg.ErrClosed
+	}
+
+	if numDocs > 0 {
+		storedIndexOffset, newDocNums, err = mergeStoredAndRemap(segments, drops,
+			fieldsMap, fieldsInv, fieldsSame, numDocs, cr, closeCh)
+		if err != nil {
+			return nil, 0, 0, 0, 0, nil, nil, nil, err
+		}
+
+		dictLocs, docValueOffset, err = persistMergedRest(segments, drops,
+			fieldsInv, fieldsMap, fieldsSame,
+			newDocNums, numDocs, chunkMode, cr, closeCh)
+		if err != nil {
+			return nil, 0, 0, 0, 0, nil, nil, nil, err
+		}
+	} else {
+		dictLocs = make([]uint64, len(fieldsInv))
+	}
+
+	fieldsIndexOffset, err = persistFields(fieldsInv, cr, dictLocs)
+	if err != nil {
+		return nil, 0, 0, 0, 0, nil, nil, nil, err
+	}
+
+	return newDocNums, numDocs, storedIndexOffset, fieldsIndexOffset, docValueOffset, dictLocs, fieldsInv, fieldsMap, nil
+}
+
+// mapFields takes the fieldsInv list and returns a map of fieldName
+// to fieldID+1
+func mapFields(fields []string) map[string]uint16 {
+	rv := make(map[string]uint16, len(fields))
+	for i, fieldName := range fields {
+		rv[fieldName] = uint16(i) + 1
+	}
+	return rv
+}
+
+// computeNewDocCount determines how many documents will be in the newly
+// merged segment when obsoleted docs are dropped
+func computeNewDocCount(segments []*SegmentBase, drops []*roaring.Bitmap) uint64 {
+	var newDocCount uint64
+	for segI, segment := range segments {
+		newDocCount += segment.numDocs
+		if drops[segI] != nil {
+			newDocCount -= drops[segI].GetCardinality()
+		}
+	}
+	return newDocCount
+}
+
+func persistMergedRest(segments []*SegmentBase, dropsIn []*roaring.Bitmap,
+	fieldsInv []string, fieldsMap map[string]uint16, fieldsSame bool,
+	newDocNumsIn [][]uint64, newSegDocCount uint64, chunkMode uint32,
+	w *CountHashWriter, closeCh chan struct{}) ([]uint64, uint64, error) {
+
+	var bufMaxVarintLen64 []byte = make([]byte, binary.MaxVarintLen64)
+	var bufLoc []uint64
+
+	var postings *PostingsList
+	var postItr *PostingsIterator
+
+	rv := make([]uint64, len(fieldsInv))
+	fieldDvLocsStart := make([]uint64, len(fieldsInv))
+	fieldDvLocsEnd := make([]uint64, len(fieldsInv))
+
+	// these int coders are initialized with chunk size 1024
+	// however this will be reset to the correct chunk size
+	// while processing each individual field-term section
+	tfEncoder := newChunkedIntCoder(1024, newSegDocCount-1)
+	locEncoder := newChunkedIntCoder(1024, newSegDocCount-1)
+
+	var vellumBuf bytes.Buffer
+	newVellum, err := vellum.New(&vellumBuf, nil)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	newRoaring := roaring.NewBitmap()
+
+	// for each field
+	for fieldID, fieldName := range fieldsInv {
+
+		// collect FST iterators from all active segments for this field
+		var newDocNums [][]uint64
+		var drops []*roaring.Bitmap
+		var dicts []*Dictionary
+		var itrs []vellum.Iterator
+
+		var segmentsInFocus []*SegmentBase
+
+		for segmentI, segment := range segments {
+
+			// check for the closure in meantime
+			if isClosed(closeCh) {
+				return nil, 0, seg.ErrClosed
+			}
+
+			dict, err2 := segment.dictionary(fieldName)
+			if err2 != nil {
+				return nil, 0, err2
+			}
+			if dict != nil && dict.fst != nil {
+				itr, err2 := dict.fst.Iterator(nil, nil)
+				if err2 != nil && err2 != vellum.ErrIteratorDone {
+					return nil, 0, err2
+				}
+				if itr != nil {
+					newDocNums = append(newDocNums, newDocNumsIn[segmentI])
+					if dropsIn[segmentI] != nil && !dropsIn[segmentI].IsEmpty() {
+						drops = append(drops, dropsIn[segmentI])
+					} else {
+						drops = append(drops, nil)
+					}
+					dicts = append(dicts, dict)
+					itrs = append(itrs, itr)
+					segmentsInFocus = append(segmentsInFocus, segment)
+				}
+			}
+		}
+
+		var prevTerm []byte
+
+		newRoaring.Clear()
+
+		var lastDocNum, lastFreq, lastNorm uint64
+
+		// determines whether to use "1-hit" encoding optimization
+		// when a term appears in only 1 doc, with no loc info,
+		// has freq of 1, and the docNum fits into 31-bits
+		use1HitEncoding := func(termCardinality uint64) (bool, uint64, uint64) {
+			if termCardinality == uint64(1) && locEncoder.FinalSize() <= 0 {
+				docNum := uint64(newRoaring.Minimum())
+				if under32Bits(docNum) && docNum == lastDocNum && lastFreq == 1 {
+					return true, docNum, lastNorm
+				}
+			}
+			return false, 0, 0
+		}
+
+		finishTerm := func(term []byte) error {
+			tfEncoder.Close()
+			locEncoder.Close()
+
+			postingsOffset, err := writePostings(newRoaring,
+				tfEncoder, locEncoder, use1HitEncoding, w, bufMaxVarintLen64)
+			if err != nil {
+				return err
+			}
+
+			if postingsOffset > 0 {
+				err = newVellum.Insert(term, postingsOffset)
+				if err != nil {
+					return err
+				}
+			}
+
+			newRoaring.Clear()
+
+			tfEncoder.Reset()
+			locEncoder.Reset()
+
+			lastDocNum = 0
+			lastFreq = 0
+			lastNorm = 0
+
+			return nil
+		}
+
+		enumerator, err := newEnumerator(itrs)
+
+		for err == nil {
+			term, itrI, postingsOffset := enumerator.Current()
+
+			if !bytes.Equal(prevTerm, term) {
+				// check for the closure in meantime
+				if isClosed(closeCh) {
+					return nil, 0, seg.ErrClosed
+				}
+
+				// if the term changed, write out the info collected
+				// for the previous term
+				err = finishTerm(prevTerm)
+				if err != nil {
+					return nil, 0, err
+				}
+			}
+			if !bytes.Equal(prevTerm, term) || prevTerm == nil {
+				// compute cardinality of field-term in new seg
+				var newCard uint64
+				lowItrIdxs, lowItrVals := enumerator.GetLowIdxsAndValues()
+				for i, idx := range lowItrIdxs {
+					pl, err := dicts[idx].postingsListFromOffset(lowItrVals[i], drops[idx], nil)
+					if err != nil {
+						return nil, 0, err
+					}
+					newCard += pl.Count()
+				}
+				// compute correct chunk size with this
+				chunkSize, err := getChunkSize(chunkMode, newCard, newSegDocCount)
+				if err != nil {
+					return nil, 0, err
+				}
+				// update encoders chunk
+				tfEncoder.SetChunkSize(chunkSize, newSegDocCount-1)
+				locEncoder.SetChunkSize(chunkSize, newSegDocCount-1)
+			}
+
+			postings, err = dicts[itrI].postingsListFromOffset(
+				postingsOffset, drops[itrI], postings)
+			if err != nil {
+				return nil, 0, err
+			}
+
+			postItr = postings.iterator(true, true, true, postItr)
+
+			// can no longer optimize by copying, since chunk factor could have changed
+			lastDocNum, lastFreq, lastNorm, bufLoc, err = mergeTermFreqNormLocs(
+				fieldsMap, term, postItr, newDocNums[itrI], newRoaring,
+				tfEncoder, locEncoder, bufLoc)
+
+			if err != nil {
+				return nil, 0, err
+			}
+
+			prevTerm = prevTerm[:0] // copy to prevTerm in case Next() reuses term mem
+			prevTerm = append(prevTerm, term...)
+
+			err = enumerator.Next()
+		}
+		if err != vellum.ErrIteratorDone {
+			return nil, 0, err
+		}
+
+		err = finishTerm(prevTerm)
+		if err != nil {
+			return nil, 0, err
+		}
+
+		dictOffset := uint64(w.Count())
+
+		err = newVellum.Close()
+		if err != nil {
+			return nil, 0, err
+		}
+		vellumData := vellumBuf.Bytes()
+
+		// write out the length of the vellum data
+		n := binary.PutUvarint(bufMaxVarintLen64, uint64(len(vellumData)))
+		_, err = w.Write(bufMaxVarintLen64[:n])
+		if err != nil {
+			return nil, 0, err
+		}
+
+		// write this vellum to disk
+		_, err = w.Write(vellumData)
+		if err != nil {
+			return nil, 0, err
+		}
+
+		rv[fieldID] = dictOffset
+
+		// get the field doc value offset (start)
+		fieldDvLocsStart[fieldID] = uint64(w.Count())
+
+		// update the field doc values
+		// NOTE: doc values continue to use legacy chunk mode
+		chunkSize, err := getChunkSize(LegacyChunkMode, 0, 0)
+		if err != nil {
+			return nil, 0, err
+		}
+		fdvEncoder := newChunkedContentCoder(chunkSize, newSegDocCount-1, w, true)
+
+		fdvReadersAvailable := false
+		var dvIterClone *docValueReader
+		for segmentI, segment := range segmentsInFocus {
+			// check for the closure in meantime
+			if isClosed(closeCh) {
+				return nil, 0, seg.ErrClosed
+			}
+
+			fieldIDPlus1 := uint16(segment.fieldsMap[fieldName])
+			if dvIter, exists := segment.fieldDvReaders[fieldIDPlus1-1]; exists &&
+				dvIter != nil {
+				fdvReadersAvailable = true
+				dvIterClone = dvIter.cloneInto(dvIterClone)
+				err = dvIterClone.iterateAllDocValues(segment, func(docNum uint64, terms []byte) error {
+					if newDocNums[segmentI][docNum] == docDropped {
+						return nil
+					}
+					err := fdvEncoder.Add(newDocNums[segmentI][docNum], terms)
+					if err != nil {
+						return err
+					}
+					return nil
+				})
+				if err != nil {
+					return nil, 0, err
+				}
+			}
+		}
+
+		if fdvReadersAvailable {
+			err = fdvEncoder.Close()
+			if err != nil {
+				return nil, 0, err
+			}
+
+			// persist the doc value details for this field
+			_, err = fdvEncoder.Write()
+			if err != nil {
+				return nil, 0, err
+			}
+
+			// get the field doc value offset (end)
+			fieldDvLocsEnd[fieldID] = uint64(w.Count())
+		} else {
+			fieldDvLocsStart[fieldID] = fieldNotUninverted
+			fieldDvLocsEnd[fieldID] = fieldNotUninverted
+		}
+
+		// reset vellum buffer and vellum builder
+		vellumBuf.Reset()
+		err = newVellum.Reset(&vellumBuf)
+		if err != nil {
+			return nil, 0, err
+		}
+	}
+
+	fieldDvLocsOffset := uint64(w.Count())
+
+	buf := bufMaxVarintLen64
+	for i := 0; i < len(fieldDvLocsStart); i++ {
+		n := binary.PutUvarint(buf, fieldDvLocsStart[i])
+		_, err := w.Write(buf[:n])
+		if err != nil {
+			return nil, 0, err
+		}
+		n = binary.PutUvarint(buf, fieldDvLocsEnd[i])
+		_, err = w.Write(buf[:n])
+		if err != nil {
+			return nil, 0, err
+		}
+	}
+
+	return rv, fieldDvLocsOffset, nil
+}
+
+func mergeTermFreqNormLocs(fieldsMap map[string]uint16, term []byte, postItr *PostingsIterator,
+	newDocNums []uint64, newRoaring *roaring.Bitmap,
+	tfEncoder *chunkedIntCoder, locEncoder *chunkedIntCoder, bufLoc []uint64) (
+	lastDocNum uint64, lastFreq uint64, lastNorm uint64, bufLocOut []uint64, err error) {
+	next, err := postItr.Next()
+	for next != nil && err == nil {
+		hitNewDocNum := newDocNums[next.Number()]
+		if hitNewDocNum == docDropped {
+			return 0, 0, 0, nil, fmt.Errorf("see hit with dropped docNum")
+		}
+
+		newRoaring.Add(uint32(hitNewDocNum))
+
+		nextFreq := next.Frequency()
+		nextNorm := uint64(math.Float32bits(float32(next.Norm())))
+
+		locs := next.Locations()
+
+		err = tfEncoder.Add(hitNewDocNum,
+			encodeFreqHasLocs(nextFreq, len(locs) > 0), nextNorm)
+		if err != nil {
+			return 0, 0, 0, nil, err
+		}
+
+		if len(locs) > 0 {
+			numBytesLocs := 0
+			for _, loc := range locs {
+				ap := loc.ArrayPositions()
+				numBytesLocs += totalUvarintBytes(uint64(fieldsMap[loc.Field()]-1),
+					loc.Pos(), loc.Start(), loc.End(), uint64(len(ap)), ap)
+			}
+
+			err = locEncoder.Add(hitNewDocNum, uint64(numBytesLocs))
+			if err != nil {
+				return 0, 0, 0, nil, err
+			}
+
+			for _, loc := range locs {
+				ap := loc.ArrayPositions()
+				if cap(bufLoc) < 5+len(ap) {
+					bufLoc = make([]uint64, 0, 5+len(ap))
+				}
+				args := bufLoc[0:5]
+				args[0] = uint64(fieldsMap[loc.Field()] - 1)
+				args[1] = loc.Pos()
+				args[2] = loc.Start()
+				args[3] = loc.End()
+				args[4] = uint64(len(ap))
+				args = append(args, ap...)
+				err = locEncoder.Add(hitNewDocNum, args...)
+				if err != nil {
+					return 0, 0, 0, nil, err
+				}
+			}
+		}
+
+		lastDocNum = hitNewDocNum
+		lastFreq = nextFreq
+		lastNorm = nextNorm
+
+		next, err = postItr.Next()
+	}
+
+	return lastDocNum, lastFreq, lastNorm, bufLoc, err
+}
+
+func writePostings(postings *roaring.Bitmap, tfEncoder, locEncoder *chunkedIntCoder,
+	use1HitEncoding func(uint64) (bool, uint64, uint64),
+	w *CountHashWriter, bufMaxVarintLen64 []byte) (
+	offset uint64, err error) {
+	termCardinality := postings.GetCardinality()
+	if termCardinality <= 0 {
+		return 0, nil
+	}
+
+	if use1HitEncoding != nil {
+		encodeAs1Hit, docNum1Hit, normBits1Hit := use1HitEncoding(termCardinality)
+		if encodeAs1Hit {
+			return FSTValEncode1Hit(docNum1Hit, normBits1Hit), nil
+		}
+	}
+
+	var tfOffset uint64
+	tfOffset, _, err = tfEncoder.writeAt(w)
+	if err != nil {
+		return 0, err
+	}
+
+	var locOffset uint64
+	locOffset, _, err = locEncoder.writeAt(w)
+	if err != nil {
+		return 0, err
+	}
+
+	postingsOffset := uint64(w.Count())
+
+	n := binary.PutUvarint(bufMaxVarintLen64, tfOffset)
+	_, err = w.Write(bufMaxVarintLen64[:n])
+	if err != nil {
+		return 0, err
+	}
+
+	n = binary.PutUvarint(bufMaxVarintLen64, locOffset)
+	_, err = w.Write(bufMaxVarintLen64[:n])
+	if err != nil {
+		return 0, err
+	}
+
+	_, err = writeRoaringWithLen(postings, w, bufMaxVarintLen64)
+	if err != nil {
+		return 0, err
+	}
+
+	return postingsOffset, nil
+}
+
+type varintEncoder func(uint64) (int, error)
+
+func mergeStoredAndRemap(segments []*SegmentBase, drops []*roaring.Bitmap,
+	fieldsMap map[string]uint16, fieldsInv []string, fieldsSame bool, newSegDocCount uint64,
+	w *CountHashWriter, closeCh chan struct{}) (uint64, [][]uint64, error) {
+	var rv [][]uint64 // The remapped or newDocNums for each segment.
+
+	var newDocNum uint64
+
+	var curr int
+	var data, compressed []byte
+	var metaBuf bytes.Buffer
+	varBuf := make([]byte, binary.MaxVarintLen64)
+	metaEncode := func(val uint64) (int, error) {
+		wb := binary.PutUvarint(varBuf, val)
+		return metaBuf.Write(varBuf[:wb])
+	}
+
+	vals := make([][][]byte, len(fieldsInv))
+	typs := make([][]byte, len(fieldsInv))
+	poss := make([][][]uint64, len(fieldsInv))
+
+	var posBuf []uint64
+
+	docNumOffsets := make([]uint64, newSegDocCount)
+
+	vdc := visitDocumentCtxPool.Get().(*visitDocumentCtx)
+	defer visitDocumentCtxPool.Put(vdc)
+
+	// for each segment
+	for segI, segment := range segments {
+		// check for the closure in meantime
+		if isClosed(closeCh) {
+			return 0, nil, seg.ErrClosed
+		}
+
+		segNewDocNums := make([]uint64, segment.numDocs)
+
+		dropsI := drops[segI]
+
+		// optimize when the field mapping is the same across all
+		// segments and there are no deletions, via byte-copying
+		// of stored docs bytes directly to the writer
+		if fieldsSame && (dropsI == nil || dropsI.GetCardinality() == 0) {
+			err := segment.copyStoredDocs(newDocNum, docNumOffsets, w)
+			if err != nil {
+				return 0, nil, err
+			}
+
+			for i := uint64(0); i < segment.numDocs; i++ {
+				segNewDocNums[i] = newDocNum
+				newDocNum++
+			}
+			rv = append(rv, segNewDocNums)
+
+			continue
+		}
+
+		// for each doc num
+		for docNum := uint64(0); docNum < segment.numDocs; docNum++ {
+			// TODO: roaring's API limits docNums to 32-bits?
+			if dropsI != nil && dropsI.Contains(uint32(docNum)) {
+				segNewDocNums[docNum] = docDropped
+				continue
+			}
+
+			segNewDocNums[docNum] = newDocNum
+
+			curr = 0
+			metaBuf.Reset()
+			data = data[:0]
+
+			posTemp := posBuf
+
+			// collect all the data
+			for i := 0; i < len(fieldsInv); i++ {
+				vals[i] = vals[i][:0]
+				typs[i] = typs[i][:0]
+				poss[i] = poss[i][:0]
+			}
+			err := segment.visitDocument(vdc, docNum, func(field string, typ byte, value []byte, pos []uint64) bool {
+				fieldID := int(fieldsMap[field]) - 1
+				vals[fieldID] = append(vals[fieldID], value)
+				typs[fieldID] = append(typs[fieldID], typ)
+
+				// copy array positions to preserve them beyond the scope of this callback
+				var curPos []uint64
+				if len(pos) > 0 {
+					if cap(posTemp) < len(pos) {
+						posBuf = make([]uint64, len(pos)*len(fieldsInv))
+						posTemp = posBuf
+					}
+					curPos = posTemp[0:len(pos)]
+					copy(curPos, pos)
+					posTemp = posTemp[len(pos):]
+				}
+				poss[fieldID] = append(poss[fieldID], curPos)
+
+				return true
+			})
+			if err != nil {
+				return 0, nil, err
+			}
+
+			// _id field special case optimizes ExternalID() lookups
+			idFieldVal := vals[uint16(0)][0]
+			_, err = metaEncode(uint64(len(idFieldVal)))
+			if err != nil {
+				return 0, nil, err
+			}
+
+			// now walk the non-"_id" fields in order
+			for fieldID := 1; fieldID < len(fieldsInv); fieldID++ {
+				storedFieldValues := vals[fieldID]
+
+				stf := typs[fieldID]
+				spf := poss[fieldID]
+
+				var err2 error
+				curr, data, err2 = persistStoredFieldValues(fieldID,
+					storedFieldValues, stf, spf, curr, metaEncode, data)
+				if err2 != nil {
+					return 0, nil, err2
+				}
+			}
+
+			metaBytes := metaBuf.Bytes()
+
+			compressed = snappy.Encode(compressed[:cap(compressed)], data)
+
+			// record where we're about to start writing
+			docNumOffsets[newDocNum] = uint64(w.Count())
+
+			// write out the meta len and compressed data len
+			_, err = writeUvarints(w,
+				uint64(len(metaBytes)),
+				uint64(len(idFieldVal)+len(compressed)))
+			if err != nil {
+				return 0, nil, err
+			}
+			// now write the meta
+			_, err = w.Write(metaBytes)
+			if err != nil {
+				return 0, nil, err
+			}
+			// now write the _id field val (counted as part of the 'compressed' data)
+			_, err = w.Write(idFieldVal)
+			if err != nil {
+				return 0, nil, err
+			}
+			// now write the compressed data
+			_, err = w.Write(compressed)
+			if err != nil {
+				return 0, nil, err
+			}
+
+			newDocNum++
+		}
+
+		rv = append(rv, segNewDocNums)
+	}
+
+	// return value is the start of the stored index
+	storedIndexOffset := uint64(w.Count())
+
+	// now write out the stored doc index
+	for _, docNumOffset := range docNumOffsets {
+		err := binary.Write(w, binary.BigEndian, docNumOffset)
+		if err != nil {
+			return 0, nil, err
+		}
+	}
+
+	return storedIndexOffset, rv, nil
+}
+
+// copyStoredDocs writes out a segment's stored doc info, optimized by
+// using a single Write() call for the entire set of bytes.  The
+// newDocNumOffsets is filled with the new offsets for each doc.
+func (s *SegmentBase) copyStoredDocs(newDocNum uint64, newDocNumOffsets []uint64,
+	w *CountHashWriter) error {
+	if s.numDocs <= 0 {
+		return nil
+	}
+
+	indexOffset0, storedOffset0, _, _, _ :=
+		s.getDocStoredOffsets(0) // the segment's first doc
+
+	indexOffsetN, storedOffsetN, readN, metaLenN, dataLenN :=
+		s.getDocStoredOffsets(s.numDocs - 1) // the segment's last doc
+
+	storedOffset0New := uint64(w.Count())
+
+	storedBytes := s.mem[storedOffset0 : storedOffsetN+readN+metaLenN+dataLenN]
+	_, err := w.Write(storedBytes)
+	if err != nil {
+		return err
+	}
+
+	// remap the storedOffset's for the docs into new offsets relative
+	// to storedOffset0New, filling the given docNumOffsetsOut array
+	for indexOffset := indexOffset0; indexOffset <= indexOffsetN; indexOffset += 8 {
+		storedOffset := binary.BigEndian.Uint64(s.mem[indexOffset : indexOffset+8])
+		storedOffsetNew := storedOffset - storedOffset0 + storedOffset0New
+		newDocNumOffsets[newDocNum] = storedOffsetNew
+		newDocNum += 1
+	}
+
+	return nil
+}
+
+// mergeFields builds a unified list of fields used across all the
+// input segments, and computes whether the fields are the same across
+// segments (which depends on fields to be sorted in the same way
+// across segments)
+func mergeFields(segments []*SegmentBase) (bool, []string) {
+	fieldsSame := true
+
+	var segment0Fields []string
+	if len(segments) > 0 {
+		segment0Fields = segments[0].Fields()
+	}
+
+	fieldsExist := map[string]struct{}{}
+	for _, segment := range segments {
+		fields := segment.Fields()
+		for fieldi, field := range fields {
+			fieldsExist[field] = struct{}{}
+			if len(segment0Fields) != len(fields) || segment0Fields[fieldi] != field {
+				fieldsSame = false
+			}
+		}
+	}
+
+	rv := make([]string, 0, len(fieldsExist))
+	// ensure _id stays first
+	rv = append(rv, "_id")
+	for k := range fieldsExist {
+		if k != "_id" {
+			rv = append(rv, k)
+		}
+	}
+
+	sort.Strings(rv[1:]) // leave _id as first
+
+	return fieldsSame, rv
+}
+
+func isClosed(closeCh chan struct{}) bool {
+	select {
+	case <-closeCh:
+		return true
+	default:
+		return false
+	}
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/new.go b/vendor/github.com/blevesearch/zap/v12/new.go
new file mode 100644
index 0000000000..98158186cb
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/new.go
@@ -0,0 +1,860 @@
+//  Copyright (c) 2018 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"encoding/binary"
+	"math"
+	"sort"
+	"sync"
+
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/analysis"
+	"github.com/blevesearch/bleve/document"
+	"github.com/blevesearch/bleve/index"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/couchbase/vellum"
+	"github.com/golang/snappy"
+)
+
+var NewSegmentBufferNumResultsBump int = 100
+var NewSegmentBufferNumResultsFactor float64 = 1.0
+var NewSegmentBufferAvgBytesPerDocFactor float64 = 1.0
+
+// ValidateDocFields can be set by applications to perform additional checks
+// on fields in a document being added to a new segment, by default it does
+// nothing.
+// This API is experimental and may be removed at any time.
+var ValidateDocFields = func(field document.Field) error {
+	return nil
+}
+
+// AnalysisResultsToSegmentBase produces an in-memory zap-encoded
+// SegmentBase from analysis results
+func (z *ZapPlugin) New(results []*index.AnalysisResult) (
+	segment.Segment, uint64, error) {
+	return z.newWithChunkMode(results, DefaultChunkMode)
+}
+
+func (*ZapPlugin) newWithChunkMode(results []*index.AnalysisResult,
+	chunkMode uint32) (segment.Segment, uint64, error) {
+	s := interimPool.Get().(*interim)
+
+	var br bytes.Buffer
+	if s.lastNumDocs > 0 {
+		// use previous results to initialize the buf with an estimate
+		// size, but note that the interim instance comes from a
+		// global interimPool, so multiple scorch instances indexing
+		// different docs can lead to low quality estimates
+		estimateAvgBytesPerDoc := int(float64(s.lastOutSize/s.lastNumDocs) *
+			NewSegmentBufferNumResultsFactor)
+		estimateNumResults := int(float64(len(results)+NewSegmentBufferNumResultsBump) *
+			NewSegmentBufferAvgBytesPerDocFactor)
+		br.Grow(estimateAvgBytesPerDoc * estimateNumResults)
+	}
+
+	s.results = results
+	s.chunkMode = chunkMode
+	s.w = NewCountHashWriter(&br)
+
+	storedIndexOffset, fieldsIndexOffset, fdvIndexOffset, dictOffsets,
+		err := s.convert()
+	if err != nil {
+		return nil, uint64(0), err
+	}
+
+	sb, err := InitSegmentBase(br.Bytes(), s.w.Sum32(), chunkMode,
+		s.FieldsMap, s.FieldsInv, uint64(len(results)),
+		storedIndexOffset, fieldsIndexOffset, fdvIndexOffset, dictOffsets)
+
+	if err == nil && s.reset() == nil {
+		s.lastNumDocs = len(results)
+		s.lastOutSize = len(br.Bytes())
+		interimPool.Put(s)
+	}
+
+	return sb, uint64(len(br.Bytes())), err
+}
+
+var interimPool = sync.Pool{New: func() interface{} { return &interim{} }}
+
+// interim holds temporary working data used while converting from
+// analysis results to a zap-encoded segment
+type interim struct {
+	results []*index.AnalysisResult
+
+	chunkMode uint32
+
+	w *CountHashWriter
+
+	// FieldsMap adds 1 to field id to avoid zero value issues
+	//  name -> field id + 1
+	FieldsMap map[string]uint16
+
+	// FieldsInv is the inverse of FieldsMap
+	//  field id -> name
+	FieldsInv []string
+
+	// Term dictionaries for each field
+	//  field id -> term -> postings list id + 1
+	Dicts []map[string]uint64
+
+	// Terms for each field, where terms are sorted ascending
+	//  field id -> []term
+	DictKeys [][]string
+
+	// Fields whose IncludeDocValues is true
+	//  field id -> bool
+	IncludeDocValues []bool
+
+	// postings id -> bitmap of docNums
+	Postings []*roaring.Bitmap
+
+	// postings id -> freq/norm's, one for each docNum in postings
+	FreqNorms        [][]interimFreqNorm
+	freqNormsBacking []interimFreqNorm
+
+	// postings id -> locs, one for each freq
+	Locs        [][]interimLoc
+	locsBacking []interimLoc
+
+	numTermsPerPostingsList []int // key is postings list id
+	numLocsPerPostingsList  []int // key is postings list id
+
+	builder    *vellum.Builder
+	builderBuf bytes.Buffer
+
+	metaBuf bytes.Buffer
+
+	tmp0 []byte
+	tmp1 []byte
+
+	lastNumDocs int
+	lastOutSize int
+}
+
+func (s *interim) reset() (err error) {
+	s.results = nil
+	s.chunkMode = 0
+	s.w = nil
+	s.FieldsMap = nil
+	s.FieldsInv = nil
+	for i := range s.Dicts {
+		s.Dicts[i] = nil
+	}
+	s.Dicts = s.Dicts[:0]
+	for i := range s.DictKeys {
+		s.DictKeys[i] = s.DictKeys[i][:0]
+	}
+	s.DictKeys = s.DictKeys[:0]
+	for i := range s.IncludeDocValues {
+		s.IncludeDocValues[i] = false
+	}
+	s.IncludeDocValues = s.IncludeDocValues[:0]
+	for _, idn := range s.Postings {
+		idn.Clear()
+	}
+	s.Postings = s.Postings[:0]
+	s.FreqNorms = s.FreqNorms[:0]
+	for i := range s.freqNormsBacking {
+		s.freqNormsBacking[i] = interimFreqNorm{}
+	}
+	s.freqNormsBacking = s.freqNormsBacking[:0]
+	s.Locs = s.Locs[:0]
+	for i := range s.locsBacking {
+		s.locsBacking[i] = interimLoc{}
+	}
+	s.locsBacking = s.locsBacking[:0]
+	s.numTermsPerPostingsList = s.numTermsPerPostingsList[:0]
+	s.numLocsPerPostingsList = s.numLocsPerPostingsList[:0]
+	s.builderBuf.Reset()
+	if s.builder != nil {
+		err = s.builder.Reset(&s.builderBuf)
+	}
+	s.metaBuf.Reset()
+	s.tmp0 = s.tmp0[:0]
+	s.tmp1 = s.tmp1[:0]
+	s.lastNumDocs = 0
+	s.lastOutSize = 0
+
+	return err
+}
+
+func (s *interim) grabBuf(size int) []byte {
+	buf := s.tmp0
+	if cap(buf) < size {
+		buf = make([]byte, size)
+		s.tmp0 = buf
+	}
+	return buf[0:size]
+}
+
+type interimStoredField struct {
+	vals      [][]byte
+	typs      []byte
+	arrayposs [][]uint64 // array positions
+}
+
+type interimFreqNorm struct {
+	freq    uint64
+	norm    float32
+	numLocs int
+}
+
+type interimLoc struct {
+	fieldID   uint16
+	pos       uint64
+	start     uint64
+	end       uint64
+	arrayposs []uint64
+}
+
+func (s *interim) convert() (uint64, uint64, uint64, []uint64, error) {
+	s.FieldsMap = map[string]uint16{}
+
+	s.getOrDefineField("_id") // _id field is fieldID 0
+
+	for _, result := range s.results {
+		for _, field := range result.Document.CompositeFields {
+			s.getOrDefineField(field.Name())
+		}
+		for _, field := range result.Document.Fields {
+			s.getOrDefineField(field.Name())
+		}
+	}
+
+	sort.Strings(s.FieldsInv[1:]) // keep _id as first field
+
+	for fieldID, fieldName := range s.FieldsInv {
+		s.FieldsMap[fieldName] = uint16(fieldID + 1)
+	}
+
+	if cap(s.IncludeDocValues) >= len(s.FieldsInv) {
+		s.IncludeDocValues = s.IncludeDocValues[:len(s.FieldsInv)]
+	} else {
+		s.IncludeDocValues = make([]bool, len(s.FieldsInv))
+	}
+
+	s.prepareDicts()
+
+	for _, dict := range s.DictKeys {
+		sort.Strings(dict)
+	}
+
+	s.processDocuments()
+
+	storedIndexOffset, err := s.writeStoredFields()
+	if err != nil {
+		return 0, 0, 0, nil, err
+	}
+
+	var fdvIndexOffset uint64
+	var dictOffsets []uint64
+
+	if len(s.results) > 0 {
+		fdvIndexOffset, dictOffsets, err = s.writeDicts()
+		if err != nil {
+			return 0, 0, 0, nil, err
+		}
+	} else {
+		dictOffsets = make([]uint64, len(s.FieldsInv))
+	}
+
+	fieldsIndexOffset, err := persistFields(s.FieldsInv, s.w, dictOffsets)
+	if err != nil {
+		return 0, 0, 0, nil, err
+	}
+
+	return storedIndexOffset, fieldsIndexOffset, fdvIndexOffset, dictOffsets, nil
+}
+
+func (s *interim) getOrDefineField(fieldName string) int {
+	fieldIDPlus1, exists := s.FieldsMap[fieldName]
+	if !exists {
+		fieldIDPlus1 = uint16(len(s.FieldsInv) + 1)
+		s.FieldsMap[fieldName] = fieldIDPlus1
+		s.FieldsInv = append(s.FieldsInv, fieldName)
+
+		s.Dicts = append(s.Dicts, make(map[string]uint64))
+
+		n := len(s.DictKeys)
+		if n < cap(s.DictKeys) {
+			s.DictKeys = s.DictKeys[:n+1]
+			s.DictKeys[n] = s.DictKeys[n][:0]
+		} else {
+			s.DictKeys = append(s.DictKeys, []string(nil))
+		}
+	}
+
+	return int(fieldIDPlus1 - 1)
+}
+
+// fill Dicts and DictKeys from analysis results
+func (s *interim) prepareDicts() {
+	var pidNext int
+
+	var totTFs int
+	var totLocs int
+
+	visitField := func(fieldID uint16, tfs analysis.TokenFrequencies) {
+		dict := s.Dicts[fieldID]
+		dictKeys := s.DictKeys[fieldID]
+
+		for term, tf := range tfs {
+			pidPlus1, exists := dict[term]
+			if !exists {
+				pidNext++
+				pidPlus1 = uint64(pidNext)
+
+				dict[term] = pidPlus1
+				dictKeys = append(dictKeys, term)
+
+				s.numTermsPerPostingsList = append(s.numTermsPerPostingsList, 0)
+				s.numLocsPerPostingsList = append(s.numLocsPerPostingsList, 0)
+			}
+
+			pid := pidPlus1 - 1
+
+			s.numTermsPerPostingsList[pid] += 1
+			s.numLocsPerPostingsList[pid] += len(tf.Locations)
+
+			totLocs += len(tf.Locations)
+		}
+
+		totTFs += len(tfs)
+
+		s.DictKeys[fieldID] = dictKeys
+	}
+
+	for _, result := range s.results {
+		// walk each composite field
+		for _, field := range result.Document.CompositeFields {
+			fieldID := uint16(s.getOrDefineField(field.Name()))
+			_, tf := field.Analyze()
+			visitField(fieldID, tf)
+		}
+
+		// walk each field
+		for i, field := range result.Document.Fields {
+			fieldID := uint16(s.getOrDefineField(field.Name()))
+			tf := result.Analyzed[i]
+			visitField(fieldID, tf)
+		}
+	}
+
+	numPostingsLists := pidNext
+
+	if cap(s.Postings) >= numPostingsLists {
+		s.Postings = s.Postings[:numPostingsLists]
+	} else {
+		postings := make([]*roaring.Bitmap, numPostingsLists)
+		copy(postings, s.Postings[:cap(s.Postings)])
+		for i := 0; i < numPostingsLists; i++ {
+			if postings[i] == nil {
+				postings[i] = roaring.New()
+			}
+		}
+		s.Postings = postings
+	}
+
+	if cap(s.FreqNorms) >= numPostingsLists {
+		s.FreqNorms = s.FreqNorms[:numPostingsLists]
+	} else {
+		s.FreqNorms = make([][]interimFreqNorm, numPostingsLists)
+	}
+
+	if cap(s.freqNormsBacking) >= totTFs {
+		s.freqNormsBacking = s.freqNormsBacking[:totTFs]
+	} else {
+		s.freqNormsBacking = make([]interimFreqNorm, totTFs)
+	}
+
+	freqNormsBacking := s.freqNormsBacking
+	for pid, numTerms := range s.numTermsPerPostingsList {
+		s.FreqNorms[pid] = freqNormsBacking[0:0]
+		freqNormsBacking = freqNormsBacking[numTerms:]
+	}
+
+	if cap(s.Locs) >= numPostingsLists {
+		s.Locs = s.Locs[:numPostingsLists]
+	} else {
+		s.Locs = make([][]interimLoc, numPostingsLists)
+	}
+
+	if cap(s.locsBacking) >= totLocs {
+		s.locsBacking = s.locsBacking[:totLocs]
+	} else {
+		s.locsBacking = make([]interimLoc, totLocs)
+	}
+
+	locsBacking := s.locsBacking
+	for pid, numLocs := range s.numLocsPerPostingsList {
+		s.Locs[pid] = locsBacking[0:0]
+		locsBacking = locsBacking[numLocs:]
+	}
+}
+
+func (s *interim) processDocuments() {
+	numFields := len(s.FieldsInv)
+	reuseFieldLens := make([]int, numFields)
+	reuseFieldTFs := make([]analysis.TokenFrequencies, numFields)
+
+	for docNum, result := range s.results {
+		for i := 0; i < numFields; i++ { // clear these for reuse
+			reuseFieldLens[i] = 0
+			reuseFieldTFs[i] = nil
+		}
+
+		s.processDocument(uint64(docNum), result,
+			reuseFieldLens, reuseFieldTFs)
+	}
+}
+
+func (s *interim) processDocument(docNum uint64,
+	result *index.AnalysisResult,
+	fieldLens []int, fieldTFs []analysis.TokenFrequencies) {
+	visitField := func(fieldID uint16, fieldName string,
+		ln int, tf analysis.TokenFrequencies) {
+		fieldLens[fieldID] += ln
+
+		existingFreqs := fieldTFs[fieldID]
+		if existingFreqs != nil {
+			existingFreqs.MergeAll(fieldName, tf)
+		} else {
+			fieldTFs[fieldID] = tf
+		}
+	}
+
+	// walk each composite field
+	for _, field := range result.Document.CompositeFields {
+		fieldID := uint16(s.getOrDefineField(field.Name()))
+		ln, tf := field.Analyze()
+		visitField(fieldID, field.Name(), ln, tf)
+	}
+
+	// walk each field
+	for i, field := range result.Document.Fields {
+		fieldID := uint16(s.getOrDefineField(field.Name()))
+		ln := result.Length[i]
+		tf := result.Analyzed[i]
+		visitField(fieldID, field.Name(), ln, tf)
+	}
+
+	// now that it's been rolled up into fieldTFs, walk that
+	for fieldID, tfs := range fieldTFs {
+		dict := s.Dicts[fieldID]
+		norm := float32(1.0 / math.Sqrt(float64(fieldLens[fieldID])))
+
+		for term, tf := range tfs {
+			pid := dict[term] - 1
+			bs := s.Postings[pid]
+			bs.Add(uint32(docNum))
+
+			s.FreqNorms[pid] = append(s.FreqNorms[pid],
+				interimFreqNorm{
+					freq:    uint64(tf.Frequency()),
+					norm:    norm,
+					numLocs: len(tf.Locations),
+				})
+
+			if len(tf.Locations) > 0 {
+				locs := s.Locs[pid]
+
+				for _, loc := range tf.Locations {
+					var locf = uint16(fieldID)
+					if loc.Field != "" {
+						locf = uint16(s.getOrDefineField(loc.Field))
+					}
+					var arrayposs []uint64
+					if len(loc.ArrayPositions) > 0 {
+						arrayposs = loc.ArrayPositions
+					}
+					locs = append(locs, interimLoc{
+						fieldID:   locf,
+						pos:       uint64(loc.Position),
+						start:     uint64(loc.Start),
+						end:       uint64(loc.End),
+						arrayposs: arrayposs,
+					})
+				}
+
+				s.Locs[pid] = locs
+			}
+		}
+	}
+}
+
+func (s *interim) writeStoredFields() (
+	storedIndexOffset uint64, err error) {
+	varBuf := make([]byte, binary.MaxVarintLen64)
+	metaEncode := func(val uint64) (int, error) {
+		wb := binary.PutUvarint(varBuf, val)
+		return s.metaBuf.Write(varBuf[:wb])
+	}
+
+	data, compressed := s.tmp0[:0], s.tmp1[:0]
+	defer func() { s.tmp0, s.tmp1 = data, compressed }()
+
+	// keyed by docNum
+	docStoredOffsets := make([]uint64, len(s.results))
+
+	// keyed by fieldID, for the current doc in the loop
+	docStoredFields := map[uint16]interimStoredField{}
+
+	for docNum, result := range s.results {
+		for fieldID := range docStoredFields { // reset for next doc
+			delete(docStoredFields, fieldID)
+		}
+
+		for _, field := range result.Document.Fields {
+			fieldID := uint16(s.getOrDefineField(field.Name()))
+
+			opts := field.Options()
+
+			if opts.IsStored() {
+				isf := docStoredFields[fieldID]
+				isf.vals = append(isf.vals, field.Value())
+				isf.typs = append(isf.typs, encodeFieldType(field))
+				isf.arrayposs = append(isf.arrayposs, field.ArrayPositions())
+				docStoredFields[fieldID] = isf
+			}
+
+			if opts.IncludeDocValues() {
+				s.IncludeDocValues[fieldID] = true
+			}
+
+			err := ValidateDocFields(field)
+			if err != nil {
+				return 0, err
+			}
+		}
+
+		var curr int
+
+		s.metaBuf.Reset()
+		data = data[:0]
+
+		// _id field special case optimizes ExternalID() lookups
+		idFieldVal := docStoredFields[uint16(0)].vals[0]
+		_, err = metaEncode(uint64(len(idFieldVal)))
+		if err != nil {
+			return 0, err
+		}
+
+		// handle non-"_id" fields
+		for fieldID := 1; fieldID < len(s.FieldsInv); fieldID++ {
+			isf, exists := docStoredFields[uint16(fieldID)]
+			if exists {
+				curr, data, err = persistStoredFieldValues(
+					fieldID, isf.vals, isf.typs, isf.arrayposs,
+					curr, metaEncode, data)
+				if err != nil {
+					return 0, err
+				}
+			}
+		}
+
+		metaBytes := s.metaBuf.Bytes()
+
+		compressed = snappy.Encode(compressed[:cap(compressed)], data)
+
+		docStoredOffsets[docNum] = uint64(s.w.Count())
+
+		_, err := writeUvarints(s.w,
+			uint64(len(metaBytes)),
+			uint64(len(idFieldVal)+len(compressed)))
+		if err != nil {
+			return 0, err
+		}
+
+		_, err = s.w.Write(metaBytes)
+		if err != nil {
+			return 0, err
+		}
+
+		_, err = s.w.Write(idFieldVal)
+		if err != nil {
+			return 0, err
+		}
+
+		_, err = s.w.Write(compressed)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	storedIndexOffset = uint64(s.w.Count())
+
+	for _, docStoredOffset := range docStoredOffsets {
+		err = binary.Write(s.w, binary.BigEndian, docStoredOffset)
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	return storedIndexOffset, nil
+}
+
+func (s *interim) writeDicts() (fdvIndexOffset uint64, dictOffsets []uint64, err error) {
+	dictOffsets = make([]uint64, len(s.FieldsInv))
+
+	fdvOffsetsStart := make([]uint64, len(s.FieldsInv))
+	fdvOffsetsEnd := make([]uint64, len(s.FieldsInv))
+
+	buf := s.grabBuf(binary.MaxVarintLen64)
+
+	// these int coders are initialized with chunk size 1024
+	// however this will be reset to the correct chunk size
+	// while processing each individual field-term section
+	tfEncoder := newChunkedIntCoder(1024, uint64(len(s.results)-1))
+	locEncoder := newChunkedIntCoder(1024, uint64(len(s.results)-1))
+
+	var docTermMap [][]byte
+
+	if s.builder == nil {
+		s.builder, err = vellum.New(&s.builderBuf, nil)
+		if err != nil {
+			return 0, nil, err
+		}
+	}
+
+	for fieldID, terms := range s.DictKeys {
+		if cap(docTermMap) < len(s.results) {
+			docTermMap = make([][]byte, len(s.results))
+		} else {
+			docTermMap = docTermMap[0:len(s.results)]
+			for docNum := range docTermMap { // reset the docTermMap
+				docTermMap[docNum] = docTermMap[docNum][:0]
+			}
+		}
+
+		dict := s.Dicts[fieldID]
+
+		for _, term := range terms { // terms are already sorted
+			pid := dict[term] - 1
+
+			postingsBS := s.Postings[pid]
+
+			freqNorms := s.FreqNorms[pid]
+			freqNormOffset := 0
+
+			locs := s.Locs[pid]
+			locOffset := 0
+
+			chunkSize, err := getChunkSize(s.chunkMode, postingsBS.GetCardinality(), uint64(len(s.results)))
+			if err != nil {
+				return 0, nil, err
+			}
+			tfEncoder.SetChunkSize(chunkSize, uint64(len(s.results)-1))
+			locEncoder.SetChunkSize(chunkSize, uint64(len(s.results)-1))
+
+			postingsItr := postingsBS.Iterator()
+			for postingsItr.HasNext() {
+				docNum := uint64(postingsItr.Next())
+
+				freqNorm := freqNorms[freqNormOffset]
+
+				err = tfEncoder.Add(docNum,
+					encodeFreqHasLocs(freqNorm.freq, freqNorm.numLocs > 0),
+					uint64(math.Float32bits(freqNorm.norm)))
+				if err != nil {
+					return 0, nil, err
+				}
+
+				if freqNorm.numLocs > 0 {
+					numBytesLocs := 0
+					for _, loc := range locs[locOffset : locOffset+freqNorm.numLocs] {
+						numBytesLocs += totalUvarintBytes(
+							uint64(loc.fieldID), loc.pos, loc.start, loc.end,
+							uint64(len(loc.arrayposs)), loc.arrayposs)
+					}
+
+					err = locEncoder.Add(docNum, uint64(numBytesLocs))
+					if err != nil {
+						return 0, nil, err
+					}
+
+					for _, loc := range locs[locOffset : locOffset+freqNorm.numLocs] {
+						err = locEncoder.Add(docNum,
+							uint64(loc.fieldID), loc.pos, loc.start, loc.end,
+							uint64(len(loc.arrayposs)))
+						if err != nil {
+							return 0, nil, err
+						}
+
+						err = locEncoder.Add(docNum, loc.arrayposs...)
+						if err != nil {
+							return 0, nil, err
+						}
+					}
+
+					locOffset += freqNorm.numLocs
+				}
+
+				freqNormOffset++
+
+				docTermMap[docNum] = append(
+					append(docTermMap[docNum], term...),
+					termSeparator)
+			}
+
+			tfEncoder.Close()
+			locEncoder.Close()
+
+			postingsOffset, err :=
+				writePostings(postingsBS, tfEncoder, locEncoder, nil, s.w, buf)
+			if err != nil {
+				return 0, nil, err
+			}
+
+			if postingsOffset > uint64(0) {
+				err = s.builder.Insert([]byte(term), postingsOffset)
+				if err != nil {
+					return 0, nil, err
+				}
+			}
+
+			tfEncoder.Reset()
+			locEncoder.Reset()
+		}
+
+		err = s.builder.Close()
+		if err != nil {
+			return 0, nil, err
+		}
+
+		// record where this dictionary starts
+		dictOffsets[fieldID] = uint64(s.w.Count())
+
+		vellumData := s.builderBuf.Bytes()
+
+		// write out the length of the vellum data
+		n := binary.PutUvarint(buf, uint64(len(vellumData)))
+		_, err = s.w.Write(buf[:n])
+		if err != nil {
+			return 0, nil, err
+		}
+
+		// write this vellum to disk
+		_, err = s.w.Write(vellumData)
+		if err != nil {
+			return 0, nil, err
+		}
+
+		// reset vellum for reuse
+		s.builderBuf.Reset()
+
+		err = s.builder.Reset(&s.builderBuf)
+		if err != nil {
+			return 0, nil, err
+		}
+
+		// write the field doc values
+		// NOTE: doc values continue to use legacy chunk mode
+		chunkSize, err := getChunkSize(LegacyChunkMode, 0, 0)
+		if err != nil {
+			return 0, nil, err
+		}
+		fdvEncoder := newChunkedContentCoder(chunkSize, uint64(len(s.results)-1), s.w, false)
+		if s.IncludeDocValues[fieldID] {
+			for docNum, docTerms := range docTermMap {
+				if len(docTerms) > 0 {
+					err = fdvEncoder.Add(uint64(docNum), docTerms)
+					if err != nil {
+						return 0, nil, err
+					}
+				}
+			}
+			err = fdvEncoder.Close()
+			if err != nil {
+				return 0, nil, err
+			}
+
+			fdvOffsetsStart[fieldID] = uint64(s.w.Count())
+
+			_, err = fdvEncoder.Write()
+			if err != nil {
+				return 0, nil, err
+			}
+
+			fdvOffsetsEnd[fieldID] = uint64(s.w.Count())
+
+			fdvEncoder.Reset()
+		} else {
+			fdvOffsetsStart[fieldID] = fieldNotUninverted
+			fdvOffsetsEnd[fieldID] = fieldNotUninverted
+		}
+	}
+
+	fdvIndexOffset = uint64(s.w.Count())
+
+	for i := 0; i < len(fdvOffsetsStart); i++ {
+		n := binary.PutUvarint(buf, fdvOffsetsStart[i])
+		_, err := s.w.Write(buf[:n])
+		if err != nil {
+			return 0, nil, err
+		}
+		n = binary.PutUvarint(buf, fdvOffsetsEnd[i])
+		_, err = s.w.Write(buf[:n])
+		if err != nil {
+			return 0, nil, err
+		}
+	}
+
+	return fdvIndexOffset, dictOffsets, nil
+}
+
+func encodeFieldType(f document.Field) byte {
+	fieldType := byte('x')
+	switch f.(type) {
+	case *document.TextField:
+		fieldType = 't'
+	case *document.NumericField:
+		fieldType = 'n'
+	case *document.DateTimeField:
+		fieldType = 'd'
+	case *document.BooleanField:
+		fieldType = 'b'
+	case *document.GeoPointField:
+		fieldType = 'g'
+	case *document.CompositeField:
+		fieldType = 'c'
+	}
+	return fieldType
+}
+
+// returns the total # of bytes needed to encode the given uint64's
+// into binary.PutUVarint() encoding
+func totalUvarintBytes(a, b, c, d, e uint64, more []uint64) (n int) {
+	n = numUvarintBytes(a)
+	n += numUvarintBytes(b)
+	n += numUvarintBytes(c)
+	n += numUvarintBytes(d)
+	n += numUvarintBytes(e)
+	for _, v := range more {
+		n += numUvarintBytes(v)
+	}
+	return n
+}
+
+// returns # of bytes needed to encode x in binary.PutUvarint() encoding
+func numUvarintBytes(x uint64) (n int) {
+	for x >= 0x80 {
+		x >>= 7
+		n++
+	}
+	return n + 1
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/plugin.go b/vendor/github.com/blevesearch/zap/v12/plugin.go
new file mode 100644
index 0000000000..38a0638d4d
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/plugin.go
@@ -0,0 +1,37 @@
+//  Copyright (c) 2020 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"github.com/blevesearch/bleve/index/scorch/segment"
+)
+
+// ZapPlugin implements the Plugin interface of
+// the blevesearch/bleve/index/scorch/segment pkg
+type ZapPlugin struct{}
+
+func (*ZapPlugin) Type() string {
+	return Type
+}
+
+func (*ZapPlugin) Version() uint32 {
+	return Version
+}
+
+// Plugin returns an instance segment.Plugin for use
+// by the Scorch indexing scheme
+func Plugin() segment.Plugin {
+	return &ZapPlugin{}
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/posting.go b/vendor/github.com/blevesearch/zap/v12/posting.go
new file mode 100644
index 0000000000..3a6ee5483a
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/posting.go
@@ -0,0 +1,798 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math"
+	"reflect"
+
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/blevesearch/bleve/size"
+)
+
+var reflectStaticSizePostingsList int
+var reflectStaticSizePostingsIterator int
+var reflectStaticSizePosting int
+var reflectStaticSizeLocation int
+
+func init() {
+	var pl PostingsList
+	reflectStaticSizePostingsList = int(reflect.TypeOf(pl).Size())
+	var pi PostingsIterator
+	reflectStaticSizePostingsIterator = int(reflect.TypeOf(pi).Size())
+	var p Posting
+	reflectStaticSizePosting = int(reflect.TypeOf(p).Size())
+	var l Location
+	reflectStaticSizeLocation = int(reflect.TypeOf(l).Size())
+}
+
+// FST or vellum value (uint64) encoding is determined by the top two
+// highest-order or most significant bits...
+//
+//  encoding  : MSB
+//  name      : 63  62  61...to...bit #0 (LSB)
+//  ----------+---+---+---------------------------------------------------
+//   general  : 0 | 0 | 62-bits of postingsOffset.
+//   ~        : 0 | 1 | reserved for future.
+//   1-hit    : 1 | 0 | 31-bits of positive float31 norm | 31-bits docNum.
+//   ~        : 1 | 1 | reserved for future.
+//
+// Encoding "general" is able to handle all cases, where the
+// postingsOffset points to more information about the postings for
+// the term.
+//
+// Encoding "1-hit" is used to optimize a commonly seen case when a
+// term has only a single hit.  For example, a term in the _id field
+// will have only 1 hit.  The "1-hit" encoding is used for a term
+// in a field when...
+//
+// - term vector info is disabled for that field;
+// - and, the term appears in only a single doc for that field;
+// - and, the term's freq is exactly 1 in that single doc for that field;
+// - and, the docNum must fit into 31-bits;
+//
+// Otherwise, the "general" encoding is used instead.
+//
+// In the "1-hit" encoding, the field in that single doc may have
+// other terms, which is supported in the "1-hit" encoding by the
+// positive float31 norm.
+
+const FSTValEncodingMask = uint64(0xc000000000000000)
+const FSTValEncodingGeneral = uint64(0x0000000000000000)
+const FSTValEncoding1Hit = uint64(0x8000000000000000)
+
+func FSTValEncode1Hit(docNum uint64, normBits uint64) uint64 {
+	return FSTValEncoding1Hit | ((mask31Bits & normBits) << 31) | (mask31Bits & docNum)
+}
+
+func FSTValDecode1Hit(v uint64) (docNum uint64, normBits uint64) {
+	return (mask31Bits & v), (mask31Bits & (v >> 31))
+}
+
+const mask31Bits = uint64(0x000000007fffffff)
+
+func under32Bits(x uint64) bool {
+	return x <= mask31Bits
+}
+
+const DocNum1HitFinished = math.MaxUint64
+
+var NormBits1Hit = uint64(math.Float32bits(float32(1)))
+
+// PostingsList is an in-memory representation of a postings list
+type PostingsList struct {
+	sb             *SegmentBase
+	postingsOffset uint64
+	freqOffset     uint64
+	locOffset      uint64
+	postings       *roaring.Bitmap
+	except         *roaring.Bitmap
+
+	// when normBits1Hit != 0, then this postings list came from a
+	// 1-hit encoding, and only the docNum1Hit & normBits1Hit apply
+	docNum1Hit   uint64
+	normBits1Hit uint64
+}
+
+// represents an immutable, empty postings list
+var emptyPostingsList = &PostingsList{}
+
+func (p *PostingsList) Size() int {
+	sizeInBytes := reflectStaticSizePostingsList + size.SizeOfPtr
+
+	if p.except != nil {
+		sizeInBytes += int(p.except.GetSizeInBytes())
+	}
+
+	return sizeInBytes
+}
+
+func (p *PostingsList) OrInto(receiver *roaring.Bitmap) {
+	if p.normBits1Hit != 0 {
+		receiver.Add(uint32(p.docNum1Hit))
+		return
+	}
+
+	if p.postings != nil {
+		receiver.Or(p.postings)
+	}
+}
+
+// Iterator returns an iterator for this postings list
+func (p *PostingsList) Iterator(includeFreq, includeNorm, includeLocs bool,
+	prealloc segment.PostingsIterator) segment.PostingsIterator {
+	if p.normBits1Hit == 0 && p.postings == nil {
+		return emptyPostingsIterator
+	}
+
+	var preallocPI *PostingsIterator
+	pi, ok := prealloc.(*PostingsIterator)
+	if ok && pi != nil {
+		preallocPI = pi
+	}
+	if preallocPI == emptyPostingsIterator {
+		preallocPI = nil
+	}
+
+	return p.iterator(includeFreq, includeNorm, includeLocs, preallocPI)
+}
+
+func (p *PostingsList) iterator(includeFreq, includeNorm, includeLocs bool,
+	rv *PostingsIterator) *PostingsIterator {
+	if rv == nil {
+		rv = &PostingsIterator{}
+	} else {
+		freqNormReader := rv.freqNormReader
+		if freqNormReader != nil {
+			freqNormReader.reset()
+		}
+
+		locReader := rv.locReader
+		if locReader != nil {
+			locReader.reset()
+		}
+
+		nextLocs := rv.nextLocs[:0]
+		nextSegmentLocs := rv.nextSegmentLocs[:0]
+
+		buf := rv.buf
+
+		*rv = PostingsIterator{} // clear the struct
+
+		rv.freqNormReader = freqNormReader
+		rv.locReader = locReader
+
+		rv.nextLocs = nextLocs
+		rv.nextSegmentLocs = nextSegmentLocs
+
+		rv.buf = buf
+	}
+
+	rv.postings = p
+	rv.includeFreqNorm = includeFreq || includeNorm || includeLocs
+	rv.includeLocs = includeLocs
+
+	if p.normBits1Hit != 0 {
+		// "1-hit" encoding
+		rv.docNum1Hit = p.docNum1Hit
+		rv.normBits1Hit = p.normBits1Hit
+
+		if p.except != nil && p.except.Contains(uint32(rv.docNum1Hit)) {
+			rv.docNum1Hit = DocNum1HitFinished
+		}
+
+		return rv
+	}
+
+	// "general" encoding, check if empty
+	if p.postings == nil {
+		return rv
+	}
+
+	// initialize freq chunk reader
+	if rv.includeFreqNorm {
+		rv.freqNormReader = newChunkedIntDecoder(p.sb.mem, p.freqOffset)
+	}
+
+	// initialize the loc chunk reader
+	if rv.includeLocs {
+		rv.locReader = newChunkedIntDecoder(p.sb.mem, p.locOffset)
+	}
+
+	rv.all = p.postings.Iterator()
+	if p.except != nil {
+		rv.ActualBM = roaring.AndNot(p.postings, p.except)
+		rv.Actual = rv.ActualBM.Iterator()
+	} else {
+		rv.ActualBM = p.postings
+		rv.Actual = rv.all // Optimize to use same iterator for all & Actual.
+	}
+
+	return rv
+}
+
+// Count returns the number of items on this postings list
+func (p *PostingsList) Count() uint64 {
+	var n, e uint64
+	if p.normBits1Hit != 0 {
+		n = 1
+		if p.except != nil && p.except.Contains(uint32(p.docNum1Hit)) {
+			e = 1
+		}
+	} else if p.postings != nil {
+		n = p.postings.GetCardinality()
+		if p.except != nil {
+			e = p.postings.AndCardinality(p.except)
+		}
+	}
+	return n - e
+}
+
+func (rv *PostingsList) read(postingsOffset uint64, d *Dictionary) error {
+	rv.postingsOffset = postingsOffset
+
+	// handle "1-hit" encoding special case
+	if rv.postingsOffset&FSTValEncodingMask == FSTValEncoding1Hit {
+		return rv.init1Hit(postingsOffset)
+	}
+
+	// read the location of the freq/norm details
+	var n uint64
+	var read int
+
+	rv.freqOffset, read = binary.Uvarint(d.sb.mem[postingsOffset+n : postingsOffset+binary.MaxVarintLen64])
+	n += uint64(read)
+
+	rv.locOffset, read = binary.Uvarint(d.sb.mem[postingsOffset+n : postingsOffset+n+binary.MaxVarintLen64])
+	n += uint64(read)
+
+	var postingsLen uint64
+	postingsLen, read = binary.Uvarint(d.sb.mem[postingsOffset+n : postingsOffset+n+binary.MaxVarintLen64])
+	n += uint64(read)
+
+	roaringBytes := d.sb.mem[postingsOffset+n : postingsOffset+n+postingsLen]
+
+	if rv.postings == nil {
+		rv.postings = roaring.NewBitmap()
+	}
+	_, err := rv.postings.FromBuffer(roaringBytes)
+	if err != nil {
+		return fmt.Errorf("error loading roaring bitmap: %v", err)
+	}
+
+	return nil
+}
+
+func (rv *PostingsList) init1Hit(fstVal uint64) error {
+	docNum, normBits := FSTValDecode1Hit(fstVal)
+
+	rv.docNum1Hit = docNum
+	rv.normBits1Hit = normBits
+
+	return nil
+}
+
+// PostingsIterator provides a way to iterate through the postings list
+type PostingsIterator struct {
+	postings *PostingsList
+	all      roaring.IntPeekable
+	Actual   roaring.IntPeekable
+	ActualBM *roaring.Bitmap
+
+	currChunk      uint32
+	freqNormReader *chunkedIntDecoder
+	locReader      *chunkedIntDecoder
+
+	next            Posting            // reused across Next() calls
+	nextLocs        []Location         // reused across Next() calls
+	nextSegmentLocs []segment.Location // reused across Next() calls
+
+	docNum1Hit   uint64
+	normBits1Hit uint64
+
+	buf []byte
+
+	includeFreqNorm bool
+	includeLocs     bool
+}
+
+var emptyPostingsIterator = &PostingsIterator{}
+
+func (i *PostingsIterator) Size() int {
+	sizeInBytes := reflectStaticSizePostingsIterator + size.SizeOfPtr +
+		i.next.Size()
+	// account for freqNormReader, locReader if we start using this.
+	for _, entry := range i.nextLocs {
+		sizeInBytes += entry.Size()
+	}
+
+	return sizeInBytes
+}
+
+func (i *PostingsIterator) loadChunk(chunk int) error {
+	if i.includeFreqNorm {
+		err := i.freqNormReader.loadChunk(chunk)
+		if err != nil {
+			return err
+		}
+	}
+
+	if i.includeLocs {
+		err := i.locReader.loadChunk(chunk)
+		if err != nil {
+			return err
+		}
+	}
+
+	i.currChunk = uint32(chunk)
+	return nil
+}
+
+func (i *PostingsIterator) readFreqNormHasLocs() (uint64, uint64, bool, error) {
+	if i.normBits1Hit != 0 {
+		return 1, i.normBits1Hit, false, nil
+	}
+
+	freqHasLocs, err := i.freqNormReader.readUvarint()
+	if err != nil {
+		return 0, 0, false, fmt.Errorf("error reading frequency: %v", err)
+	}
+
+	freq, hasLocs := decodeFreqHasLocs(freqHasLocs)
+
+	normBits, err := i.freqNormReader.readUvarint()
+	if err != nil {
+		return 0, 0, false, fmt.Errorf("error reading norm: %v", err)
+	}
+
+	return freq, normBits, hasLocs, nil
+}
+
+func (i *PostingsIterator) skipFreqNormReadHasLocs() (bool, error) {
+	if i.normBits1Hit != 0 {
+		return false, nil
+	}
+
+	freqHasLocs, err := i.freqNormReader.readUvarint()
+	if err != nil {
+		return false, fmt.Errorf("error reading freqHasLocs: %v", err)
+	}
+
+	i.freqNormReader.SkipUvarint() // Skip normBits.
+
+	return freqHasLocs&0x01 != 0, nil // See decodeFreqHasLocs() / hasLocs.
+}
+
+func encodeFreqHasLocs(freq uint64, hasLocs bool) uint64 {
+	rv := freq << 1
+	if hasLocs {
+		rv = rv | 0x01 // 0'th LSB encodes whether there are locations
+	}
+	return rv
+}
+
+func decodeFreqHasLocs(freqHasLocs uint64) (uint64, bool) {
+	freq := freqHasLocs >> 1
+	hasLocs := freqHasLocs&0x01 != 0
+	return freq, hasLocs
+}
+
+// readLocation processes all the integers on the stream representing a single
+// location.
+func (i *PostingsIterator) readLocation(l *Location) error {
+	// read off field
+	fieldID, err := i.locReader.readUvarint()
+	if err != nil {
+		return fmt.Errorf("error reading location field: %v", err)
+	}
+	// read off pos
+	pos, err := i.locReader.readUvarint()
+	if err != nil {
+		return fmt.Errorf("error reading location pos: %v", err)
+	}
+	// read off start
+	start, err := i.locReader.readUvarint()
+	if err != nil {
+		return fmt.Errorf("error reading location start: %v", err)
+	}
+	// read off end
+	end, err := i.locReader.readUvarint()
+	if err != nil {
+		return fmt.Errorf("error reading location end: %v", err)
+	}
+	// read off num array pos
+	numArrayPos, err := i.locReader.readUvarint()
+	if err != nil {
+		return fmt.Errorf("error reading location num array pos: %v", err)
+	}
+
+	l.field = i.postings.sb.fieldsInv[fieldID]
+	l.pos = pos
+	l.start = start
+	l.end = end
+
+	if cap(l.ap) < int(numArrayPos) {
+		l.ap = make([]uint64, int(numArrayPos))
+	} else {
+		l.ap = l.ap[:int(numArrayPos)]
+	}
+
+	// read off array positions
+	for k := 0; k < int(numArrayPos); k++ {
+		ap, err := i.locReader.readUvarint()
+		if err != nil {
+			return fmt.Errorf("error reading array position: %v", err)
+		}
+
+		l.ap[k] = ap
+	}
+
+	return nil
+}
+
+// Next returns the next posting on the postings list, or nil at the end
+func (i *PostingsIterator) Next() (segment.Posting, error) {
+	return i.nextAtOrAfter(0)
+}
+
+// Advance returns the posting at the specified docNum or it is not present
+// the next posting, or if the end is reached, nil
+func (i *PostingsIterator) Advance(docNum uint64) (segment.Posting, error) {
+	return i.nextAtOrAfter(docNum)
+}
+
+// Next returns the next posting on the postings list, or nil at the end
+func (i *PostingsIterator) nextAtOrAfter(atOrAfter uint64) (segment.Posting, error) {
+	docNum, exists, err := i.nextDocNumAtOrAfter(atOrAfter)
+	if err != nil || !exists {
+		return nil, err
+	}
+
+	i.next = Posting{} // clear the struct
+	rv := &i.next
+	rv.docNum = docNum
+
+	if !i.includeFreqNorm {
+		return rv, nil
+	}
+
+	var normBits uint64
+	var hasLocs bool
+
+	rv.freq, normBits, hasLocs, err = i.readFreqNormHasLocs()
+	if err != nil {
+		return nil, err
+	}
+
+	rv.norm = math.Float32frombits(uint32(normBits))
+
+	if i.includeLocs && hasLocs {
+		// prepare locations into reused slices, where we assume
+		// rv.freq >= "number of locs", since in a composite field,
+		// some component fields might have their IncludeTermVector
+		// flags disabled while other component fields are enabled
+		if cap(i.nextLocs) >= int(rv.freq) {
+			i.nextLocs = i.nextLocs[0:rv.freq]
+		} else {
+			i.nextLocs = make([]Location, rv.freq, rv.freq*2)
+		}
+		if cap(i.nextSegmentLocs) < int(rv.freq) {
+			i.nextSegmentLocs = make([]segment.Location, rv.freq, rv.freq*2)
+		}
+		rv.locs = i.nextSegmentLocs[:0]
+
+		numLocsBytes, err := i.locReader.readUvarint()
+		if err != nil {
+			return nil, fmt.Errorf("error reading location numLocsBytes: %v", err)
+		}
+
+		j := 0
+		startBytesRemaining := i.locReader.Len() // # bytes remaining in the locReader
+		for startBytesRemaining-i.locReader.Len() < int(numLocsBytes) {
+			err := i.readLocation(&i.nextLocs[j])
+			if err != nil {
+				return nil, err
+			}
+			rv.locs = append(rv.locs, &i.nextLocs[j])
+			j++
+		}
+	}
+
+	return rv, nil
+}
+
+// nextDocNum returns the next docNum on the postings list, and also
+// sets up the currChunk / loc related fields of the iterator.
+func (i *PostingsIterator) nextDocNumAtOrAfter(atOrAfter uint64) (uint64, bool, error) {
+	if i.normBits1Hit != 0 {
+		if i.docNum1Hit == DocNum1HitFinished {
+			return 0, false, nil
+		}
+		if i.docNum1Hit < atOrAfter {
+			// advanced past our 1-hit
+			i.docNum1Hit = DocNum1HitFinished // consume our 1-hit docNum
+			return 0, false, nil
+		}
+		docNum := i.docNum1Hit
+		i.docNum1Hit = DocNum1HitFinished // consume our 1-hit docNum
+		return docNum, true, nil
+	}
+
+	if i.Actual == nil || !i.Actual.HasNext() {
+		return 0, false, nil
+	}
+
+	if i.postings == nil || i.postings.postings == i.ActualBM {
+		return i.nextDocNumAtOrAfterClean(atOrAfter)
+	}
+
+	i.Actual.AdvanceIfNeeded(uint32(atOrAfter))
+
+	if !i.Actual.HasNext() {
+		// couldn't find anything
+		return 0, false, nil
+	}
+
+	n := i.Actual.Next()
+	allN := i.all.Next()
+
+	chunkSize, err := getChunkSize(i.postings.sb.chunkMode, i.postings.postings.GetCardinality(), i.postings.sb.numDocs)
+	if err != nil {
+		return 0, false, err
+	}
+	nChunk := n / uint32(chunkSize)
+
+	// when allN becomes >= to here, then allN is in the same chunk as nChunk.
+	allNReachesNChunk := nChunk * uint32(chunkSize)
+
+	// n is the next actual hit (excluding some postings), and
+	// allN is the next hit in the full postings, and
+	// if they don't match, move 'all' forwards until they do
+	for allN != n {
+		// we've reached same chunk, so move the freq/norm/loc decoders forward
+		if i.includeFreqNorm && allN >= allNReachesNChunk {
+			err := i.currChunkNext(nChunk)
+			if err != nil {
+				return 0, false, err
+			}
+		}
+
+		allN = i.all.Next()
+	}
+
+	if i.includeFreqNorm && (i.currChunk != nChunk || i.freqNormReader.isNil()) {
+		err := i.loadChunk(int(nChunk))
+		if err != nil {
+			return 0, false, fmt.Errorf("error loading chunk: %v", err)
+		}
+	}
+
+	return uint64(n), true, nil
+}
+
+// optimization when the postings list is "clean" (e.g., no updates &
+// no deletions) where the all bitmap is the same as the actual bitmap
+func (i *PostingsIterator) nextDocNumAtOrAfterClean(
+	atOrAfter uint64) (uint64, bool, error) {
+
+	if !i.includeFreqNorm {
+		i.Actual.AdvanceIfNeeded(uint32(atOrAfter))
+
+		if !i.Actual.HasNext() {
+			return 0, false, nil // couldn't find anything
+		}
+
+		return uint64(i.Actual.Next()), true, nil
+	}
+
+	chunkSize, err := getChunkSize(i.postings.sb.chunkMode, i.postings.postings.GetCardinality(), i.postings.sb.numDocs)
+	if err != nil {
+		return 0, false, err
+	}
+
+	// freq-norm's needed, so maintain freq-norm chunk reader
+	sameChunkNexts := 0 // # of times we called Next() in the same chunk
+	n := i.Actual.Next()
+	nChunk := n / uint32(chunkSize)
+
+	for uint64(n) < atOrAfter && i.Actual.HasNext() {
+		n = i.Actual.Next()
+
+		nChunkPrev := nChunk
+		nChunk = n / uint32(chunkSize)
+
+		if nChunk != nChunkPrev {
+			sameChunkNexts = 0
+		} else {
+			sameChunkNexts += 1
+		}
+	}
+
+	if uint64(n) < atOrAfter {
+		// couldn't find anything
+		return 0, false, nil
+	}
+
+	for j := 0; j < sameChunkNexts; j++ {
+		err := i.currChunkNext(nChunk)
+		if err != nil {
+			return 0, false, fmt.Errorf("error optimized currChunkNext: %v", err)
+		}
+	}
+
+	if i.currChunk != nChunk || i.freqNormReader.isNil() {
+		err := i.loadChunk(int(nChunk))
+		if err != nil {
+			return 0, false, fmt.Errorf("error loading chunk: %v", err)
+		}
+	}
+
+	return uint64(n), true, nil
+}
+
+func (i *PostingsIterator) currChunkNext(nChunk uint32) error {
+	if i.currChunk != nChunk || i.freqNormReader.isNil() {
+		err := i.loadChunk(int(nChunk))
+		if err != nil {
+			return fmt.Errorf("error loading chunk: %v", err)
+		}
+	}
+
+	// read off freq/offsets even though we don't care about them
+	hasLocs, err := i.skipFreqNormReadHasLocs()
+	if err != nil {
+		return err
+	}
+
+	if i.includeLocs && hasLocs {
+		numLocsBytes, err := i.locReader.readUvarint()
+		if err != nil {
+			return fmt.Errorf("error reading location numLocsBytes: %v", err)
+		}
+
+		// skip over all the location bytes
+		i.locReader.SkipBytes(int(numLocsBytes))
+	}
+
+	return nil
+}
+
+// DocNum1Hit returns the docNum and true if this is "1-hit" optimized
+// and the docNum is available.
+func (p *PostingsIterator) DocNum1Hit() (uint64, bool) {
+	if p.normBits1Hit != 0 && p.docNum1Hit != DocNum1HitFinished {
+		return p.docNum1Hit, true
+	}
+	return 0, false
+}
+
+// ActualBitmap returns the underlying actual bitmap
+// which can be used up the stack for optimizations
+func (p *PostingsIterator) ActualBitmap() *roaring.Bitmap {
+	return p.ActualBM
+}
+
+// ReplaceActual replaces the ActualBM with the provided
+// bitmap
+func (p *PostingsIterator) ReplaceActual(abm *roaring.Bitmap) {
+	p.ActualBM = abm
+	p.Actual = abm.Iterator()
+}
+
+// PostingsIteratorFromBitmap constructs a PostingsIterator given an
+// "actual" bitmap.
+func PostingsIteratorFromBitmap(bm *roaring.Bitmap,
+	includeFreqNorm, includeLocs bool) (segment.PostingsIterator, error) {
+	return &PostingsIterator{
+		ActualBM:        bm,
+		Actual:          bm.Iterator(),
+		includeFreqNorm: includeFreqNorm,
+		includeLocs:     includeLocs,
+	}, nil
+}
+
+// PostingsIteratorFrom1Hit constructs a PostingsIterator given a
+// 1-hit docNum.
+func PostingsIteratorFrom1Hit(docNum1Hit uint64,
+	includeFreqNorm, includeLocs bool) (segment.PostingsIterator, error) {
+	return &PostingsIterator{
+		docNum1Hit:      docNum1Hit,
+		normBits1Hit:    NormBits1Hit,
+		includeFreqNorm: includeFreqNorm,
+		includeLocs:     includeLocs,
+	}, nil
+}
+
+// Posting is a single entry in a postings list
+type Posting struct {
+	docNum uint64
+	freq   uint64
+	norm   float32
+	locs   []segment.Location
+}
+
+func (p *Posting) Size() int {
+	sizeInBytes := reflectStaticSizePosting
+
+	for _, entry := range p.locs {
+		sizeInBytes += entry.Size()
+	}
+
+	return sizeInBytes
+}
+
+// Number returns the document number of this posting in this segment
+func (p *Posting) Number() uint64 {
+	return p.docNum
+}
+
+// Frequency returns the frequencies of occurrence of this term in this doc/field
+func (p *Posting) Frequency() uint64 {
+	return p.freq
+}
+
+// Norm returns the normalization factor for this posting
+func (p *Posting) Norm() float64 {
+	return float64(p.norm)
+}
+
+// Locations returns the location information for each occurrence
+func (p *Posting) Locations() []segment.Location {
+	return p.locs
+}
+
+// Location represents the location of a single occurrence
+type Location struct {
+	field string
+	pos   uint64
+	start uint64
+	end   uint64
+	ap    []uint64
+}
+
+func (l *Location) Size() int {
+	return reflectStaticSizeLocation +
+		len(l.field) +
+		len(l.ap)*size.SizeOfUint64
+}
+
+// Field returns the name of the field (useful in composite fields to know
+// which original field the value came from)
+func (l *Location) Field() string {
+	return l.field
+}
+
+// Start returns the start byte offset of this occurrence
+func (l *Location) Start() uint64 {
+	return l.start
+}
+
+// End returns the end byte offset of this occurrence
+func (l *Location) End() uint64 {
+	return l.end
+}
+
+// Pos returns the 1-based phrase position of this occurrence
+func (l *Location) Pos() uint64 {
+	return l.pos
+}
+
+// ArrayPositions returns the array position vector associated with this occurrence
+func (l *Location) ArrayPositions() []uint64 {
+	return l.ap
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/read.go b/vendor/github.com/blevesearch/zap/v12/read.go
new file mode 100644
index 0000000000..e47d4c6abd
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/read.go
@@ -0,0 +1,43 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import "encoding/binary"
+
+func (s *SegmentBase) getDocStoredMetaAndCompressed(docNum uint64) ([]byte, []byte) {
+	_, storedOffset, n, metaLen, dataLen := s.getDocStoredOffsets(docNum)
+
+	meta := s.mem[storedOffset+n : storedOffset+n+metaLen]
+	data := s.mem[storedOffset+n+metaLen : storedOffset+n+metaLen+dataLen]
+
+	return meta, data
+}
+
+func (s *SegmentBase) getDocStoredOffsets(docNum uint64) (
+	uint64, uint64, uint64, uint64, uint64) {
+	indexOffset := s.storedIndexOffset + (8 * docNum)
+
+	storedOffset := binary.BigEndian.Uint64(s.mem[indexOffset : indexOffset+8])
+
+	var n uint64
+
+	metaLen, read := binary.Uvarint(s.mem[storedOffset : storedOffset+binary.MaxVarintLen64])
+	n += uint64(read)
+
+	dataLen, read := binary.Uvarint(s.mem[storedOffset+n : storedOffset+n+binary.MaxVarintLen64])
+	n += uint64(read)
+
+	return indexOffset, storedOffset, n, metaLen, dataLen
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/segment.go b/vendor/github.com/blevesearch/zap/v12/segment.go
new file mode 100644
index 0000000000..e8b1f067fe
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/segment.go
@@ -0,0 +1,572 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"os"
+	"sync"
+	"unsafe"
+
+	"github.com/RoaringBitmap/roaring"
+	"github.com/blevesearch/bleve/index/scorch/segment"
+	"github.com/blevesearch/bleve/size"
+	"github.com/couchbase/vellum"
+	mmap "github.com/blevesearch/mmap-go"
+	"github.com/golang/snappy"
+)
+
+var reflectStaticSizeSegmentBase int
+
+func init() {
+	var sb SegmentBase
+	reflectStaticSizeSegmentBase = int(unsafe.Sizeof(sb))
+}
+
+// Open returns a zap impl of a segment
+func (*ZapPlugin) Open(path string) (segment.Segment, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return nil, err
+	}
+	mm, err := mmap.Map(f, mmap.RDONLY, 0)
+	if err != nil {
+		// mmap failed, try to close the file
+		_ = f.Close()
+		return nil, err
+	}
+
+	rv := &Segment{
+		SegmentBase: SegmentBase{
+			mem:            mm[0 : len(mm)-FooterSize],
+			fieldsMap:      make(map[string]uint16),
+			fieldDvReaders: make(map[uint16]*docValueReader),
+			fieldFSTs:      make(map[uint16]*vellum.FST),
+		},
+		f:    f,
+		mm:   mm,
+		path: path,
+		refs: 1,
+	}
+	rv.SegmentBase.updateSize()
+
+	err = rv.loadConfig()
+	if err != nil {
+		_ = rv.Close()
+		return nil, err
+	}
+
+	err = rv.loadFields()
+	if err != nil {
+		_ = rv.Close()
+		return nil, err
+	}
+
+	err = rv.loadDvReaders()
+	if err != nil {
+		_ = rv.Close()
+		return nil, err
+	}
+
+	return rv, nil
+}
+
+// SegmentBase is a memory only, read-only implementation of the
+// segment.Segment interface, using zap's data representation.
+type SegmentBase struct {
+	mem               []byte
+	memCRC            uint32
+	chunkMode         uint32
+	fieldsMap         map[string]uint16 // fieldName -> fieldID+1
+	fieldsInv         []string          // fieldID -> fieldName
+	numDocs           uint64
+	storedIndexOffset uint64
+	fieldsIndexOffset uint64
+	docValueOffset    uint64
+	dictLocs          []uint64
+	fieldDvReaders    map[uint16]*docValueReader // naive chunk cache per field
+	fieldDvNames      []string                   // field names cached in fieldDvReaders
+	size              uint64
+
+	m         sync.Mutex
+	fieldFSTs map[uint16]*vellum.FST
+}
+
+func (sb *SegmentBase) Size() int {
+	return int(sb.size)
+}
+
+func (sb *SegmentBase) updateSize() {
+	sizeInBytes := reflectStaticSizeSegmentBase +
+		cap(sb.mem)
+
+	// fieldsMap
+	for k := range sb.fieldsMap {
+		sizeInBytes += (len(k) + size.SizeOfString) + size.SizeOfUint16
+	}
+
+	// fieldsInv, dictLocs
+	for _, entry := range sb.fieldsInv {
+		sizeInBytes += len(entry) + size.SizeOfString
+	}
+	sizeInBytes += len(sb.dictLocs) * size.SizeOfUint64
+
+	// fieldDvReaders
+	for _, v := range sb.fieldDvReaders {
+		sizeInBytes += size.SizeOfUint16 + size.SizeOfPtr
+		if v != nil {
+			sizeInBytes += v.size()
+		}
+	}
+
+	sb.size = uint64(sizeInBytes)
+}
+
+func (sb *SegmentBase) AddRef()             {}
+func (sb *SegmentBase) DecRef() (err error) { return nil }
+func (sb *SegmentBase) Close() (err error)  { return nil }
+
+// Segment implements a persisted segment.Segment interface, by
+// embedding an mmap()'ed SegmentBase.
+type Segment struct {
+	SegmentBase
+
+	f       *os.File
+	mm      mmap.MMap
+	path    string
+	version uint32
+	crc     uint32
+
+	m    sync.Mutex // Protects the fields that follow.
+	refs int64
+}
+
+func (s *Segment) Size() int {
+	// 8 /* size of file pointer */
+	// 4 /* size of version -> uint32 */
+	// 4 /* size of crc -> uint32 */
+	sizeOfUints := 16
+
+	sizeInBytes := (len(s.path) + size.SizeOfString) + sizeOfUints
+
+	// mutex, refs -> int64
+	sizeInBytes += 16
+
+	// do not include the mmap'ed part
+	return sizeInBytes + s.SegmentBase.Size() - cap(s.mem)
+}
+
+func (s *Segment) AddRef() {
+	s.m.Lock()
+	s.refs++
+	s.m.Unlock()
+}
+
+func (s *Segment) DecRef() (err error) {
+	s.m.Lock()
+	s.refs--
+	if s.refs == 0 {
+		err = s.closeActual()
+	}
+	s.m.Unlock()
+	return err
+}
+
+func (s *Segment) loadConfig() error {
+	crcOffset := len(s.mm) - 4
+	s.crc = binary.BigEndian.Uint32(s.mm[crcOffset : crcOffset+4])
+
+	verOffset := crcOffset - 4
+	s.version = binary.BigEndian.Uint32(s.mm[verOffset : verOffset+4])
+	if s.version != Version {
+		return fmt.Errorf("unsupported version %d", s.version)
+	}
+
+	chunkOffset := verOffset - 4
+	s.chunkMode = binary.BigEndian.Uint32(s.mm[chunkOffset : chunkOffset+4])
+
+	docValueOffset := chunkOffset - 8
+	s.docValueOffset = binary.BigEndian.Uint64(s.mm[docValueOffset : docValueOffset+8])
+
+	fieldsIndexOffset := docValueOffset - 8
+	s.fieldsIndexOffset = binary.BigEndian.Uint64(s.mm[fieldsIndexOffset : fieldsIndexOffset+8])
+
+	storedIndexOffset := fieldsIndexOffset - 8
+	s.storedIndexOffset = binary.BigEndian.Uint64(s.mm[storedIndexOffset : storedIndexOffset+8])
+
+	numDocsOffset := storedIndexOffset - 8
+	s.numDocs = binary.BigEndian.Uint64(s.mm[numDocsOffset : numDocsOffset+8])
+	return nil
+}
+
+func (s *SegmentBase) loadFields() error {
+	// NOTE for now we assume the fields index immediately precedes
+	// the footer, and if this changes, need to adjust accordingly (or
+	// store explicit length), where s.mem was sliced from s.mm in Open().
+	fieldsIndexEnd := uint64(len(s.mem))
+
+	// iterate through fields index
+	var fieldID uint64
+	for s.fieldsIndexOffset+(8*fieldID) < fieldsIndexEnd {
+		addr := binary.BigEndian.Uint64(s.mem[s.fieldsIndexOffset+(8*fieldID) : s.fieldsIndexOffset+(8*fieldID)+8])
+
+		dictLoc, read := binary.Uvarint(s.mem[addr:fieldsIndexEnd])
+		n := uint64(read)
+		s.dictLocs = append(s.dictLocs, dictLoc)
+
+		var nameLen uint64
+		nameLen, read = binary.Uvarint(s.mem[addr+n : fieldsIndexEnd])
+		n += uint64(read)
+
+		name := string(s.mem[addr+n : addr+n+nameLen])
+		s.fieldsInv = append(s.fieldsInv, name)
+		s.fieldsMap[name] = uint16(fieldID + 1)
+
+		fieldID++
+	}
+	return nil
+}
+
+// Dictionary returns the term dictionary for the specified field
+func (s *SegmentBase) Dictionary(field string) (segment.TermDictionary, error) {
+	dict, err := s.dictionary(field)
+	if err == nil && dict == nil {
+		return &segment.EmptyDictionary{}, nil
+	}
+	return dict, err
+}
+
+func (sb *SegmentBase) dictionary(field string) (rv *Dictionary, err error) {
+	fieldIDPlus1 := sb.fieldsMap[field]
+	if fieldIDPlus1 > 0 {
+		rv = &Dictionary{
+			sb:      sb,
+			field:   field,
+			fieldID: fieldIDPlus1 - 1,
+		}
+
+		dictStart := sb.dictLocs[rv.fieldID]
+		if dictStart > 0 {
+			var ok bool
+			sb.m.Lock()
+			if rv.fst, ok = sb.fieldFSTs[rv.fieldID]; !ok {
+				// read the length of the vellum data
+				vellumLen, read := binary.Uvarint(sb.mem[dictStart : dictStart+binary.MaxVarintLen64])
+				fstBytes := sb.mem[dictStart+uint64(read) : dictStart+uint64(read)+vellumLen]
+				rv.fst, err = vellum.Load(fstBytes)
+				if err != nil {
+					sb.m.Unlock()
+					return nil, fmt.Errorf("dictionary field %s vellum err: %v", field, err)
+				}
+
+				sb.fieldFSTs[rv.fieldID] = rv.fst
+			}
+
+			sb.m.Unlock()
+			rv.fstReader, err = rv.fst.Reader()
+			if err != nil {
+				return nil, fmt.Errorf("dictionary field %s vellum reader err: %v", field, err)
+			}
+
+		}
+	}
+
+	return rv, nil
+}
+
+// visitDocumentCtx holds data structures that are reusable across
+// multiple VisitDocument() calls to avoid memory allocations
+type visitDocumentCtx struct {
+	buf      []byte
+	reader   bytes.Reader
+	arrayPos []uint64
+}
+
+var visitDocumentCtxPool = sync.Pool{
+	New: func() interface{} {
+		reuse := &visitDocumentCtx{}
+		return reuse
+	},
+}
+
+// VisitDocument invokes the DocFieldValueVistor for each stored field
+// for the specified doc number
+func (s *SegmentBase) VisitDocument(num uint64, visitor segment.DocumentFieldValueVisitor) error {
+	vdc := visitDocumentCtxPool.Get().(*visitDocumentCtx)
+	defer visitDocumentCtxPool.Put(vdc)
+	return s.visitDocument(vdc, num, visitor)
+}
+
+func (s *SegmentBase) visitDocument(vdc *visitDocumentCtx, num uint64,
+	visitor segment.DocumentFieldValueVisitor) error {
+	// first make sure this is a valid number in this segment
+	if num < s.numDocs {
+		meta, compressed := s.getDocStoredMetaAndCompressed(num)
+
+		vdc.reader.Reset(meta)
+
+		// handle _id field special case
+		idFieldValLen, err := binary.ReadUvarint(&vdc.reader)
+		if err != nil {
+			return err
+		}
+		idFieldVal := compressed[:idFieldValLen]
+
+		keepGoing := visitor("_id", byte('t'), idFieldVal, nil)
+		if !keepGoing {
+			visitDocumentCtxPool.Put(vdc)
+			return nil
+		}
+
+		// handle non-"_id" fields
+		compressed = compressed[idFieldValLen:]
+
+		uncompressed, err := snappy.Decode(vdc.buf[:cap(vdc.buf)], compressed)
+		if err != nil {
+			return err
+		}
+
+		for keepGoing {
+			field, err := binary.ReadUvarint(&vdc.reader)
+			if err == io.EOF {
+				break
+			}
+			if err != nil {
+				return err
+			}
+			typ, err := binary.ReadUvarint(&vdc.reader)
+			if err != nil {
+				return err
+			}
+			offset, err := binary.ReadUvarint(&vdc.reader)
+			if err != nil {
+				return err
+			}
+			l, err := binary.ReadUvarint(&vdc.reader)
+			if err != nil {
+				return err
+			}
+			numap, err := binary.ReadUvarint(&vdc.reader)
+			if err != nil {
+				return err
+			}
+			var arrayPos []uint64
+			if numap > 0 {
+				if cap(vdc.arrayPos) < int(numap) {
+					vdc.arrayPos = make([]uint64, numap)
+				}
+				arrayPos = vdc.arrayPos[:numap]
+				for i := 0; i < int(numap); i++ {
+					ap, err := binary.ReadUvarint(&vdc.reader)
+					if err != nil {
+						return err
+					}
+					arrayPos[i] = ap
+				}
+			}
+
+			value := uncompressed[offset : offset+l]
+			keepGoing = visitor(s.fieldsInv[field], byte(typ), value, arrayPos)
+		}
+
+		vdc.buf = uncompressed
+	}
+	return nil
+}
+
+// DocID returns the value of the _id field for the given docNum
+func (s *SegmentBase) DocID(num uint64) ([]byte, error) {
+	if num >= s.numDocs {
+		return nil, nil
+	}
+
+	vdc := visitDocumentCtxPool.Get().(*visitDocumentCtx)
+
+	meta, compressed := s.getDocStoredMetaAndCompressed(num)
+
+	vdc.reader.Reset(meta)
+
+	// handle _id field special case
+	idFieldValLen, err := binary.ReadUvarint(&vdc.reader)
+	if err != nil {
+		return nil, err
+	}
+	idFieldVal := compressed[:idFieldValLen]
+
+	visitDocumentCtxPool.Put(vdc)
+
+	return idFieldVal, nil
+}
+
+// Count returns the number of documents in this segment.
+func (s *SegmentBase) Count() uint64 {
+	return s.numDocs
+}
+
+// DocNumbers returns a bitset corresponding to the doc numbers of all the
+// provided _id strings
+func (s *SegmentBase) DocNumbers(ids []string) (*roaring.Bitmap, error) {
+	rv := roaring.New()
+
+	if len(s.fieldsMap) > 0 {
+		idDict, err := s.dictionary("_id")
+		if err != nil {
+			return nil, err
+		}
+
+		postingsList := emptyPostingsList
+
+		sMax, err := idDict.fst.GetMaxKey()
+		if err != nil {
+			return nil, err
+		}
+		sMaxStr := string(sMax)
+		filteredIds := make([]string, 0, len(ids))
+		for _, id := range ids {
+			if id <= sMaxStr {
+				filteredIds = append(filteredIds, id)
+			}
+		}
+
+		for _, id := range filteredIds {
+			postingsList, err = idDict.postingsList([]byte(id), nil, postingsList)
+			if err != nil {
+				return nil, err
+			}
+			postingsList.OrInto(rv)
+		}
+	}
+
+	return rv, nil
+}
+
+// Fields returns the field names used in this segment
+func (s *SegmentBase) Fields() []string {
+	return s.fieldsInv
+}
+
+// Path returns the path of this segment on disk
+func (s *Segment) Path() string {
+	return s.path
+}
+
+// Close releases all resources associated with this segment
+func (s *Segment) Close() (err error) {
+	return s.DecRef()
+}
+
+func (s *Segment) closeActual() (err error) {
+	if s.mm != nil {
+		err = s.mm.Unmap()
+	}
+	// try to close file even if unmap failed
+	if s.f != nil {
+		err2 := s.f.Close()
+		if err == nil {
+			// try to return first error
+			err = err2
+		}
+	}
+	return
+}
+
+// some helpers i started adding for the command-line utility
+
+// Data returns the underlying mmaped data slice
+func (s *Segment) Data() []byte {
+	return s.mm
+}
+
+// CRC returns the CRC value stored in the file footer
+func (s *Segment) CRC() uint32 {
+	return s.crc
+}
+
+// Version returns the file version in the file footer
+func (s *Segment) Version() uint32 {
+	return s.version
+}
+
+// ChunkFactor returns the chunk factor in the file footer
+func (s *Segment) ChunkMode() uint32 {
+	return s.chunkMode
+}
+
+// FieldsIndexOffset returns the fields index offset in the file footer
+func (s *Segment) FieldsIndexOffset() uint64 {
+	return s.fieldsIndexOffset
+}
+
+// StoredIndexOffset returns the stored value index offset in the file footer
+func (s *Segment) StoredIndexOffset() uint64 {
+	return s.storedIndexOffset
+}
+
+// DocValueOffset returns the docValue offset in the file footer
+func (s *Segment) DocValueOffset() uint64 {
+	return s.docValueOffset
+}
+
+// NumDocs returns the number of documents in the file footer
+func (s *Segment) NumDocs() uint64 {
+	return s.numDocs
+}
+
+// DictAddr is a helper function to compute the file offset where the
+// dictionary is stored for the specified field.
+func (s *Segment) DictAddr(field string) (uint64, error) {
+	fieldIDPlus1, ok := s.fieldsMap[field]
+	if !ok {
+		return 0, fmt.Errorf("no such field '%s'", field)
+	}
+
+	return s.dictLocs[fieldIDPlus1-1], nil
+}
+
+func (s *SegmentBase) loadDvReaders() error {
+	if s.docValueOffset == fieldNotUninverted || s.numDocs == 0 {
+		return nil
+	}
+
+	var read uint64
+	for fieldID, field := range s.fieldsInv {
+		var fieldLocStart, fieldLocEnd uint64
+		var n int
+		fieldLocStart, n = binary.Uvarint(s.mem[s.docValueOffset+read : s.docValueOffset+read+binary.MaxVarintLen64])
+		if n <= 0 {
+			return fmt.Errorf("loadDvReaders: failed to read the docvalue offset start for field %d", fieldID)
+		}
+		read += uint64(n)
+		fieldLocEnd, n = binary.Uvarint(s.mem[s.docValueOffset+read : s.docValueOffset+read+binary.MaxVarintLen64])
+		if n <= 0 {
+			return fmt.Errorf("loadDvReaders: failed to read the docvalue offset end for field %d", fieldID)
+		}
+		read += uint64(n)
+
+		fieldDvReader, err := s.loadFieldDocValueReader(field, fieldLocStart, fieldLocEnd)
+		if err != nil {
+			return err
+		}
+		if fieldDvReader != nil {
+			s.fieldDvReaders[uint16(fieldID)] = fieldDvReader
+			s.fieldDvNames = append(s.fieldDvNames, field)
+		}
+	}
+
+	return nil
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/write.go b/vendor/github.com/blevesearch/zap/v12/write.go
new file mode 100644
index 0000000000..77aefdbfc8
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/write.go
@@ -0,0 +1,145 @@
+//  Copyright (c) 2017 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package zap
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/RoaringBitmap/roaring"
+)
+
+// writes out the length of the roaring bitmap in bytes as varint
+// then writes out the roaring bitmap itself
+func writeRoaringWithLen(r *roaring.Bitmap, w io.Writer,
+	reuseBufVarint []byte) (int, error) {
+	buf, err := r.ToBytes()
+	if err != nil {
+		return 0, err
+	}
+
+	var tw int
+
+	// write out the length
+	n := binary.PutUvarint(reuseBufVarint, uint64(len(buf)))
+	nw, err := w.Write(reuseBufVarint[:n])
+	tw += nw
+	if err != nil {
+		return tw, err
+	}
+
+	// write out the roaring bytes
+	nw, err = w.Write(buf)
+	tw += nw
+	if err != nil {
+		return tw, err
+	}
+
+	return tw, nil
+}
+
+func persistFields(fieldsInv []string, w *CountHashWriter, dictLocs []uint64) (uint64, error) {
+	var rv uint64
+	var fieldsOffsets []uint64
+
+	for fieldID, fieldName := range fieldsInv {
+		// record start of this field
+		fieldsOffsets = append(fieldsOffsets, uint64(w.Count()))
+
+		// write out the dict location and field name length
+		_, err := writeUvarints(w, dictLocs[fieldID], uint64(len(fieldName)))
+		if err != nil {
+			return 0, err
+		}
+
+		// write out the field name
+		_, err = w.Write([]byte(fieldName))
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	// now write out the fields index
+	rv = uint64(w.Count())
+	for fieldID := range fieldsInv {
+		err := binary.Write(w, binary.BigEndian, fieldsOffsets[fieldID])
+		if err != nil {
+			return 0, err
+		}
+	}
+
+	return rv, nil
+}
+
+// FooterSize is the size of the footer record in bytes
+// crc + ver + chunk + field offset + stored offset + num docs + docValueOffset
+const FooterSize = 4 + 4 + 4 + 8 + 8 + 8 + 8
+
+func persistFooter(numDocs, storedIndexOffset, fieldsIndexOffset, docValueOffset uint64,
+	chunkMode uint32, crcBeforeFooter uint32, writerIn io.Writer) error {
+	w := NewCountHashWriter(writerIn)
+	w.crc = crcBeforeFooter
+
+	// write out the number of docs
+	err := binary.Write(w, binary.BigEndian, numDocs)
+	if err != nil {
+		return err
+	}
+	// write out the stored field index location:
+	err = binary.Write(w, binary.BigEndian, storedIndexOffset)
+	if err != nil {
+		return err
+	}
+	// write out the field index location
+	err = binary.Write(w, binary.BigEndian, fieldsIndexOffset)
+	if err != nil {
+		return err
+	}
+	// write out the fieldDocValue location
+	err = binary.Write(w, binary.BigEndian, docValueOffset)
+	if err != nil {
+		return err
+	}
+	// write out 32-bit chunk factor
+	err = binary.Write(w, binary.BigEndian, chunkMode)
+	if err != nil {
+		return err
+	}
+	// write out 32-bit version
+	err = binary.Write(w, binary.BigEndian, Version)
+	if err != nil {
+		return err
+	}
+	// write out CRC-32 of everything upto but not including this CRC
+	err = binary.Write(w, binary.BigEndian, w.crc)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func writeUvarints(w io.Writer, vals ...uint64) (tw int, err error) {
+	buf := make([]byte, binary.MaxVarintLen64)
+	for _, val := range vals {
+		n := binary.PutUvarint(buf, val)
+		var nw int
+		nw, err = w.Write(buf[:n])
+		tw += nw
+		if err != nil {
+			return tw, err
+		}
+	}
+	return tw, err
+}
diff --git a/vendor/github.com/blevesearch/zap/v12/zap.md b/vendor/github.com/blevesearch/zap/v12/zap.md
new file mode 100644
index 0000000000..d74dc548b8
--- /dev/null
+++ b/vendor/github.com/blevesearch/zap/v12/zap.md
@@ -0,0 +1,177 @@
+# ZAP File Format 
+
+## Legend
+
+### Sections
+
+    |========|
+    |        | section
+    |========|
+    
+### Fixed-size fields
+
+    |--------|        |----|        |--|        |-|
+    |        | uint64 |    | uint32 |  | uint16 | | uint8
+    |--------|        |----|        |--|        |-|
+
+### Varints
+
+    |~~~~~~~~|
+    |        | varint(up to uint64)
+    |~~~~~~~~|
+
+### Arbitrary-length fields
+
+    |--------...---|
+    |              | arbitrary-length field (string, vellum, roaring bitmap)
+    |--------...---|
+
+### Chunked data
+
+	[--------]
+	[        ]
+	[--------]
+
+## Overview
+
+Footer section describes the configuration of particular ZAP file. The format of footer is version-dependent, so it is necessary to check `V` field before the parsing.
+
+            |==================================================|
+            | Stored Fields                                    |
+            |==================================================|
+    |-----> | Stored Fields Index                              |
+    |       |==================================================|   
+    |       | Dictionaries + Postings + DocValues              | 
+    |       |==================================================|
+    | |---> | DocValues Index                                  |
+    | |     |==================================================|   
+    | |     | Fields                                           |
+    | |     |==================================================|
+    | | |-> | Fields Index                                     |
+    | | |   |========|========|========|========|====|====|====|
+    | | |   |     D# |     SF |      F |    FDV | CF |  V | CC | (Footer)
+    | | |   |========|====|===|====|===|====|===|====|====|====|
+    | | |                 |        |        |
+    |-+-+-----------------|        |        |
+      | |--------------------------|        |
+      |-------------------------------------|
+
+     D#. Number of Docs.
+     SF. Stored Fields Index Offset.
+      F. Field Index Offset.
+    FDV. Field DocValue Offset.
+     CF. Chunk Factor.
+      V. Version.
+     CC. CRC32.
+
+## Stored Fields
+
+Stored Fields Index is `D#` consecutive 64-bit unsigned integers - offsets, where relevant Stored Fields Data records are located.
+
+    0                                [SF]                   [SF + D# * 8]
+    | Stored Fields                  | Stored Fields Index              |
+    |================================|==================================|
+    |                                |                                  |
+    |       |--------------------|   ||--------|--------|. . .|--------||
+    |   |-> | Stored Fields Data |   ||      0 |      1 |     | D# - 1 ||
+    |   |   |--------------------|   ||--------|----|---|. . .|--------||
+    |   |                            |              |                   |
+    |===|============================|==============|===================|
+        |                                           |
+        |-------------------------------------------|
+
+Stored Fields Data is an arbitrary size record, which consists of metadata and [Snappy](https://github.com/golang/snappy)-compressed data.
+
+    Stored Fields Data
+    |~~~~~~~~|~~~~~~~~|~~~~~~~~...~~~~~~~~|~~~~~~~~...~~~~~~~~|
+    |    MDS |    CDS |                MD |                CD |
+    |~~~~~~~~|~~~~~~~~|~~~~~~~~...~~~~~~~~|~~~~~~~~...~~~~~~~~|
+    
+    MDS. Metadata size.
+    CDS. Compressed data size.
+    MD. Metadata.
+    CD. Snappy-compressed data.
+
+## Fields
+
+Fields Index section located between addresses `F` and `len(file) - len(footer)` and consist of `uint64` values (`F1`, `F2`, ...) which are offsets to records in Fields section. We have `F# = (len(file) - len(footer) - F) / sizeof(uint64)` fields.
+
+
+    (...)                            [F]                       [F + F#]
+    | Fields                         | Fields Index.                  |
+    |================================|================================|
+    |                                |                                |
+    |   |~~~~~~~~|~~~~~~~~|---...---|||--------|--------|...|--------||
+    ||->|   Dict | Length |    Name |||      0 |      1 |   | F# - 1 ||
+    ||  |~~~~~~~~|~~~~~~~~|---...---|||--------|----|---|...|--------||
+    ||                               |              |                 |
+    ||===============================|==============|=================|
+     |                                              |
+     |----------------------------------------------|
+        
+
+## Dictionaries + Postings
+
+Each of fields has its own dictionary, encoded in [Vellum](https://github.com/couchbase/vellum) format. Dictionary consists of pairs `(term, offset)`, where `offset` indicates the position of postings (list of documents) for this particular term.
+
+	|================================================================|- Dictionaries + 
+	|                                                                |   Postings +
+	|                                                                |    DocValues
+	|    Freq/Norm (chunked)                                         |
+	|    [~~~~~~|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~]                      |
+	| |->[ Freq | Norm (float32 under varint) ]                      |
+	| |  [~~~~~~|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~]                      |
+	| |                                                              |
+	| |------------------------------------------------------------| |
+	|    Location Details (chunked)                                | |
+	|    [~~~~~~|~~~~~|~~~~~~~|~~~~~|~~~~~~|~~~~~~~~|~~~~~]        | |
+	| |->[ Size | Pos | Start | End | Arr# | ArrPos | ... ]        | |
+	| |  [~~~~~~|~~~~~|~~~~~~~|~~~~~|~~~~~~|~~~~~~~~|~~~~~]        | |
+	| |                                                            | |
+	| |----------------------|                                     | |
+	|          Postings List |                                     | |
+	|         |~~~~~~~~|~~~~~|~~|~~~~~~~~|-----------...--|        | |
+	|      |->|    F/N |     LD | Length | ROARING BITMAP |        | |
+	|      |  |~~~~~|~~|~~~~~~~~|~~~~~~~~|-----------...--|        | |
+	|      |        |----------------------------------------------| |
+	|      |--------------------------------------|                  |
+	|          Dictionary                         |                  |
+	|         |~~~~~~~~|--------------------------|-...-|            |
+	|      |->| Length | VELLUM DATA : (TERM -> OFFSET) |            |
+	|      |  |~~~~~~~~|----------------------------...-|            |
+	|      |                                                         |
+	|======|=========================================================|- DocValues Index
+	|      |                                                         |
+	|======|=========================================================|- Fields
+	|      |                                                         |
+	| |~~~~|~~~|~~~~~~~~|---...---|                                  |
+	| |   Dict | Length |    Name |                                  |
+	| |~~~~~~~~|~~~~~~~~|---...---|                                  |
+	|                                                                |
+	|================================================================|
+
+## DocValues
+
+DocValues Index is `F#` pairs of varints, one pair per field. Each pair of varints indicates start and end point of DocValues slice.
+
+	|================================================================|
+	|     |------...--|                                              |
+	|  |->| DocValues |<-|                                           |
+	|  |  |------...--|  |                                           |
+	|==|=================|===========================================|- DocValues Index
+	||~|~~~~~~~~~|~~~~~~~|~~|           |~~~~~~~~~~~~~~|~~~~~~~~~~~~||
+	|| DV1 START | DV1 STOP | . . . . . | DV(F#) START | DV(F#) END ||
+	||~~~~~~~~~~~|~~~~~~~~~~|           |~~~~~~~~~~~~~~|~~~~~~~~~~~~||
+	|================================================================|
+
+DocValues is chunked Snappy-compressed values for each document and field.
+
+    [~~~~~~~~~~~~~~~|~~~~~~|~~~~~~~~~|-...-|~~~~~~|~~~~~~~~~|--------------------...-]
+    [ Doc# in Chunk | Doc1 | Offset1 | ... | DocN | OffsetN | SNAPPY COMPRESSED DATA ]
+    [~~~~~~~~~~~~~~~|~~~~~~|~~~~~~~~~|-...-|~~~~~~|~~~~~~~~~|--------------------...-]
+
+Last 16 bytes are description of chunks.
+
+    |~~~~~~~~~~~~...~|----------------|----------------|
+    |   Chunk Sizes  | Chunk Size Arr |         Chunk# |
+    |~~~~~~~~~~~~...~|----------------|----------------|
diff --git a/vendor/github.com/couchbase/vellum/go.mod b/vendor/github.com/couchbase/vellum/go.mod
index 0e304159d4..ef9d9abfb0 100644
--- a/vendor/github.com/couchbase/vellum/go.mod
+++ b/vendor/github.com/couchbase/vellum/go.mod
@@ -3,7 +3,7 @@ module github.com/couchbase/vellum
 go 1.12
 
 require (
-	github.com/edsrzf/mmap-go v1.0.0
+	github.com/blevesearch/mmap-go v1.0.2
 	github.com/spf13/cobra v0.0.5
 	github.com/willf/bitset v1.1.10
 	golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a // indirect
diff --git a/vendor/github.com/couchbase/vellum/go.sum b/vendor/github.com/couchbase/vellum/go.sum
index f14998530d..1022e684eb 100644
--- a/vendor/github.com/couchbase/vellum/go.sum
+++ b/vendor/github.com/couchbase/vellum/go.sum
@@ -1,12 +1,12 @@
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
+github.com/blevesearch/mmap-go v1.0.2 h1:JtMHb+FgQCTTYIhtMvimw15dJwu1Y5lrZDMOFXVWPk0=
+github.com/blevesearch/mmap-go v1.0.2/go.mod h1:ol2qBqYaOUsGdm7aRMRrYGgPvnwLe6Y+7LMvAB5IbSA=
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/edsrzf/mmap-go v1.0.0 h1:CEBF7HpRnUCSJgGUb5h1Gm7e3VkmVDrR8lvWVLtrOFw=
-github.com/edsrzf/mmap-go v1.0.0/go.mod h1:YO35OhQPt3KJa3ryjFM5Bs14WD66h8eGKpfaBNrHW5M=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
 github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
@@ -32,6 +32,7 @@ github.com/willf/bitset v1.1.10/go.mod h1:RjeCKbqT1RxIR/KWY6phxZiaY1IyutSBfGjNPy
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20181221143128-b4a75ba826a6/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a h1:aYOabOQFp6Vj6W1F80affTUvO9UxmJRx8K0gsfABByQ=
 golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/vendor/github.com/couchbase/vellum/vellum_mmap.go b/vendor/github.com/couchbase/vellum/vellum_mmap.go
index 5acd2f4707..81ea165091 100644
--- a/vendor/github.com/couchbase/vellum/vellum_mmap.go
+++ b/vendor/github.com/couchbase/vellum/vellum_mmap.go
@@ -19,7 +19,7 @@ package vellum
 import (
 	"os"
 
-	mmap "github.com/edsrzf/mmap-go"
+	mmap "github.com/blevesearch/mmap-go"
 )
 
 type mmapWrapper struct {
diff --git a/vendor/github.com/etcd-io/bbolt/.gitignore b/vendor/github.com/etcd-io/bbolt/.gitignore
deleted file mode 100644
index 3bcd8cbaf0..0000000000
--- a/vendor/github.com/etcd-io/bbolt/.gitignore
+++ /dev/null
@@ -1,5 +0,0 @@
-*.prof
-*.test
-*.swp
-/bin/
-cover.out
diff --git a/vendor/github.com/etcd-io/bbolt/.travis.yml b/vendor/github.com/etcd-io/bbolt/.travis.yml
deleted file mode 100644
index a60300c558..0000000000
--- a/vendor/github.com/etcd-io/bbolt/.travis.yml
+++ /dev/null
@@ -1,17 +0,0 @@
-language: go
-go_import_path: go.etcd.io/bbolt
-
-sudo: false
-
-go:
-- 1.11
-
-before_install:
-- go get -v honnef.co/go/tools/...
-- go get -v github.com/kisielk/errcheck
-
-script:
-- make fmt
-- make test
-- make race
-# - make errcheck
diff --git a/vendor/github.com/etcd-io/bbolt/LICENSE b/vendor/github.com/etcd-io/bbolt/LICENSE
deleted file mode 100644
index 004e77fe5d..0000000000
--- a/vendor/github.com/etcd-io/bbolt/LICENSE
+++ /dev/null
@@ -1,20 +0,0 @@
-The MIT License (MIT)
-
-Copyright (c) 2013 Ben Johnson
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-the Software, and to permit persons to whom the Software is furnished to do so,
-subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/vendor/github.com/etcd-io/bbolt/Makefile b/vendor/github.com/etcd-io/bbolt/Makefile
deleted file mode 100644
index 2968aaa61d..0000000000
--- a/vendor/github.com/etcd-io/bbolt/Makefile
+++ /dev/null
@@ -1,38 +0,0 @@
-BRANCH=`git rev-parse --abbrev-ref HEAD`
-COMMIT=`git rev-parse --short HEAD`
-GOLDFLAGS="-X main.branch $(BRANCH) -X main.commit $(COMMIT)"
-
-default: build
-
-race:
-	@TEST_FREELIST_TYPE=hashmap go test -v -race -test.run="TestSimulate_(100op|1000op)"
-	@echo "array freelist test"
-	@TEST_FREELIST_TYPE=array go test -v -race -test.run="TestSimulate_(100op|1000op)"
-
-fmt:
-	!(gofmt -l -s -d $(shell find . -name \*.go) | grep '[a-z]')
-
-# go get honnef.co/go/tools/simple
-gosimple:
-	gosimple ./...
-
-# go get honnef.co/go/tools/unused
-unused:
-	unused ./...
-
-# go get github.com/kisielk/errcheck
-errcheck:
-	@errcheck -ignorepkg=bytes -ignore=os:Remove go.etcd.io/bbolt
-
-test:
-	TEST_FREELIST_TYPE=hashmap go test -timeout 20m -v -coverprofile cover.out -covermode atomic
-	# Note: gets "program not an importable package" in out of path builds
-	TEST_FREELIST_TYPE=hashmap go test -v ./cmd/bbolt
-
-	@echo "array freelist test"
-
-	@TEST_FREELIST_TYPE=array go test -timeout 20m -v -coverprofile cover.out -covermode atomic
-	# Note: gets "program not an importable package" in out of path builds
-	@TEST_FREELIST_TYPE=array go test -v ./cmd/bbolt
-
-.PHONY: race fmt errcheck test gosimple unused
diff --git a/vendor/github.com/etcd-io/bbolt/README.md b/vendor/github.com/etcd-io/bbolt/README.md
deleted file mode 100644
index e9989efc50..0000000000
--- a/vendor/github.com/etcd-io/bbolt/README.md
+++ /dev/null
@@ -1,954 +0,0 @@
-bbolt
-=====
-
-[![Go Report Card](https://goreportcard.com/badge/github.com/etcd-io/bbolt?style=flat-square)](https://goreportcard.com/report/github.com/etcd-io/bbolt)
-[![Coverage](https://codecov.io/gh/etcd-io/bbolt/branch/master/graph/badge.svg)](https://codecov.io/gh/etcd-io/bbolt)
-[![Build Status Travis](https://img.shields.io/travis/etcd-io/bboltlabs.svg?style=flat-square&&branch=master)](https://travis-ci.com/etcd-io/bbolt)
-[![Godoc](http://img.shields.io/badge/go-documentation-blue.svg?style=flat-square)](https://godoc.org/github.com/etcd-io/bbolt)
-[![Releases](https://img.shields.io/github/release/etcd-io/bbolt/all.svg?style=flat-square)](https://github.com/etcd-io/bbolt/releases)
-[![LICENSE](https://img.shields.io/github/license/etcd-io/bbolt.svg?style=flat-square)](https://github.com/etcd-io/bbolt/blob/master/LICENSE)
-
-bbolt is a fork of [Ben Johnson's][gh_ben] [Bolt][bolt] key/value
-store. The purpose of this fork is to provide the Go community with an active
-maintenance and development target for Bolt; the goal is improved reliability
-and stability. bbolt includes bug fixes, performance enhancements, and features
-not found in Bolt while preserving backwards compatibility with the Bolt API.
-
-Bolt is a pure Go key/value store inspired by [Howard Chu's][hyc_symas]
-[LMDB project][lmdb]. The goal of the project is to provide a simple,
-fast, and reliable database for projects that don't require a full database
-server such as Postgres or MySQL.
-
-Since Bolt is meant to be used as such a low-level piece of functionality,
-simplicity is key. The API will be small and only focus on getting values
-and setting values. That's it.
-
-[gh_ben]: https://github.com/benbjohnson
-[bolt]: https://github.com/boltdb/bolt
-[hyc_symas]: https://twitter.com/hyc_symas
-[lmdb]: http://symas.com/mdb/
-
-## Project Status
-
-Bolt is stable, the API is fixed, and the file format is fixed. Full unit
-test coverage and randomized black box testing are used to ensure database
-consistency and thread safety. Bolt is currently used in high-load production
-environments serving databases as large as 1TB. Many companies such as
-Shopify and Heroku use Bolt-backed services every day.
-
-## Project versioning
-
-bbolt uses [semantic versioning](http://semver.org).
-API should not change between patch and minor releases.
-New minor versions may add additional features to the API.
-
-## Table of Contents
-
-  - [Getting Started](#getting-started)
-    - [Installing](#installing)
-    - [Opening a database](#opening-a-database)
-    - [Transactions](#transactions)
-      - [Read-write transactions](#read-write-transactions)
-      - [Read-only transactions](#read-only-transactions)
-      - [Batch read-write transactions](#batch-read-write-transactions)
-      - [Managing transactions manually](#managing-transactions-manually)
-    - [Using buckets](#using-buckets)
-    - [Using key/value pairs](#using-keyvalue-pairs)
-    - [Autoincrementing integer for the bucket](#autoincrementing-integer-for-the-bucket)
-    - [Iterating over keys](#iterating-over-keys)
-      - [Prefix scans](#prefix-scans)
-      - [Range scans](#range-scans)
-      - [ForEach()](#foreach)
-    - [Nested buckets](#nested-buckets)
-    - [Database backups](#database-backups)
-    - [Statistics](#statistics)
-    - [Read-Only Mode](#read-only-mode)
-    - [Mobile Use (iOS/Android)](#mobile-use-iosandroid)
-  - [Resources](#resources)
-  - [Comparison with other databases](#comparison-with-other-databases)
-    - [Postgres, MySQL, & other relational databases](#postgres-mysql--other-relational-databases)
-    - [LevelDB, RocksDB](#leveldb-rocksdb)
-    - [LMDB](#lmdb)
-  - [Caveats & Limitations](#caveats--limitations)
-  - [Reading the Source](#reading-the-source)
-  - [Other Projects Using Bolt](#other-projects-using-bolt)
-
-## Getting Started
-
-### Installing
-
-To start using Bolt, install Go and run `go get`:
-
-```sh
-$ go get go.etcd.io/bbolt/...
-```
-
-This will retrieve the library and install the `bolt` command line utility into
-your `$GOBIN` path.
-
-
-### Importing bbolt
-
-To use bbolt as an embedded key-value store, import as:
-
-```go
-import bolt "go.etcd.io/bbolt"
-
-db, err := bolt.Open(path, 0666, nil)
-if err != nil {
-  return err
-}
-defer db.Close()
-```
-
-
-### Opening a database
-
-The top-level object in Bolt is a `DB`. It is represented as a single file on
-your disk and represents a consistent snapshot of your data.
-
-To open your database, simply use the `bolt.Open()` function:
-
-```go
-package main
-
-import (
-	"log"
-
-	bolt "go.etcd.io/bbolt"
-)
-
-func main() {
-	// Open the my.db data file in your current directory.
-	// It will be created if it doesn't exist.
-	db, err := bolt.Open("my.db", 0600, nil)
-	if err != nil {
-		log.Fatal(err)
-	}
-	defer db.Close()
-
-	...
-}
-```
-
-Please note that Bolt obtains a file lock on the data file so multiple processes
-cannot open the same database at the same time. Opening an already open Bolt
-database will cause it to hang until the other process closes it. To prevent
-an indefinite wait you can pass a timeout option to the `Open()` function:
-
-```go
-db, err := bolt.Open("my.db", 0600, &bolt.Options{Timeout: 1 * time.Second})
-```
-
-
-### Transactions
-
-Bolt allows only one read-write transaction at a time but allows as many
-read-only transactions as you want at a time. Each transaction has a consistent
-view of the data as it existed when the transaction started.
-
-Individual transactions and all objects created from them (e.g. buckets, keys)
-are not thread safe. To work with data in multiple goroutines you must start
-a transaction for each one or use locking to ensure only one goroutine accesses
-a transaction at a time. Creating transaction from the `DB` is thread safe.
-
-Read-only transactions and read-write transactions should not depend on one
-another and generally shouldn't be opened simultaneously in the same goroutine.
-This can cause a deadlock as the read-write transaction needs to periodically
-re-map the data file but it cannot do so while a read-only transaction is open.
-
-
-#### Read-write transactions
-
-To start a read-write transaction, you can use the `DB.Update()` function:
-
-```go
-err := db.Update(func(tx *bolt.Tx) error {
-	...
-	return nil
-})
-```
-
-Inside the closure, you have a consistent view of the database. You commit the
-transaction by returning `nil` at the end. You can also rollback the transaction
-at any point by returning an error. All database operations are allowed inside
-a read-write transaction.
-
-Always check the return error as it will report any disk failures that can cause
-your transaction to not complete. If you return an error within your closure
-it will be passed through.
-
-
-#### Read-only transactions
-
-To start a read-only transaction, you can use the `DB.View()` function:
-
-```go
-err := db.View(func(tx *bolt.Tx) error {
-	...
-	return nil
-})
-```
-
-You also get a consistent view of the database within this closure, however,
-no mutating operations are allowed within a read-only transaction. You can only
-retrieve buckets, retrieve values, and copy the database within a read-only
-transaction.
-
-
-#### Batch read-write transactions
-
-Each `DB.Update()` waits for disk to commit the writes. This overhead
-can be minimized by combining multiple updates with the `DB.Batch()`
-function:
-
-```go
-err := db.Batch(func(tx *bolt.Tx) error {
-	...
-	return nil
-})
-```
-
-Concurrent Batch calls are opportunistically combined into larger
-transactions. Batch is only useful when there are multiple goroutines
-calling it.
-
-The trade-off is that `Batch` can call the given
-function multiple times, if parts of the transaction fail. The
-function must be idempotent and side effects must take effect only
-after a successful return from `DB.Batch()`.
-
-For example: don't display messages from inside the function, instead
-set variables in the enclosing scope:
-
-```go
-var id uint64
-err := db.Batch(func(tx *bolt.Tx) error {
-	// Find last key in bucket, decode as bigendian uint64, increment
-	// by one, encode back to []byte, and add new key.
-	...
-	id = newValue
-	return nil
-})
-if err != nil {
-	return ...
-}
-fmt.Println("Allocated ID %d", id)
-```
-
-
-#### Managing transactions manually
-
-The `DB.View()` and `DB.Update()` functions are wrappers around the `DB.Begin()`
-function. These helper functions will start the transaction, execute a function,
-and then safely close your transaction if an error is returned. This is the
-recommended way to use Bolt transactions.
-
-However, sometimes you may want to manually start and end your transactions.
-You can use the `DB.Begin()` function directly but **please** be sure to close
-the transaction.
-
-```go
-// Start a writable transaction.
-tx, err := db.Begin(true)
-if err != nil {
-    return err
-}
-defer tx.Rollback()
-
-// Use the transaction...
-_, err := tx.CreateBucket([]byte("MyBucket"))
-if err != nil {
-    return err
-}
-
-// Commit the transaction and check for error.
-if err := tx.Commit(); err != nil {
-    return err
-}
-```
-
-The first argument to `DB.Begin()` is a boolean stating if the transaction
-should be writable.
-
-
-### Using buckets
-
-Buckets are collections of key/value pairs within the database. All keys in a
-bucket must be unique. You can create a bucket using the `DB.CreateBucket()`
-function:
-
-```go
-db.Update(func(tx *bolt.Tx) error {
-	b, err := tx.CreateBucket([]byte("MyBucket"))
-	if err != nil {
-		return fmt.Errorf("create bucket: %s", err)
-	}
-	return nil
-})
-```
-
-You can also create a bucket only if it doesn't exist by using the
-`Tx.CreateBucketIfNotExists()` function. It's a common pattern to call this
-function for all your top-level buckets after you open your database so you can
-guarantee that they exist for future transactions.
-
-To delete a bucket, simply call the `Tx.DeleteBucket()` function.
-
-
-### Using key/value pairs
-
-To save a key/value pair to a bucket, use the `Bucket.Put()` function:
-
-```go
-db.Update(func(tx *bolt.Tx) error {
-	b := tx.Bucket([]byte("MyBucket"))
-	err := b.Put([]byte("answer"), []byte("42"))
-	return err
-})
-```
-
-This will set the value of the `"answer"` key to `"42"` in the `MyBucket`
-bucket. To retrieve this value, we can use the `Bucket.Get()` function:
-
-```go
-db.View(func(tx *bolt.Tx) error {
-	b := tx.Bucket([]byte("MyBucket"))
-	v := b.Get([]byte("answer"))
-	fmt.Printf("The answer is: %s\n", v)
-	return nil
-})
-```
-
-The `Get()` function does not return an error because its operation is
-guaranteed to work (unless there is some kind of system failure). If the key
-exists then it will return its byte slice value. If it doesn't exist then it
-will return `nil`. It's important to note that you can have a zero-length value
-set to a key which is different than the key not existing.
-
-Use the `Bucket.Delete()` function to delete a key from the bucket.
-
-Please note that values returned from `Get()` are only valid while the
-transaction is open. If you need to use a value outside of the transaction
-then you must use `copy()` to copy it to another byte slice.
-
-
-### Autoincrementing integer for the bucket
-By using the `NextSequence()` function, you can let Bolt determine a sequence
-which can be used as the unique identifier for your key/value pairs. See the
-example below.
-
-```go
-// CreateUser saves u to the store. The new user ID is set on u once the data is persisted.
-func (s *Store) CreateUser(u *User) error {
-    return s.db.Update(func(tx *bolt.Tx) error {
-        // Retrieve the users bucket.
-        // This should be created when the DB is first opened.
-        b := tx.Bucket([]byte("users"))
-
-        // Generate ID for the user.
-        // This returns an error only if the Tx is closed or not writeable.
-        // That can't happen in an Update() call so I ignore the error check.
-        id, _ := b.NextSequence()
-        u.ID = int(id)
-
-        // Marshal user data into bytes.
-        buf, err := json.Marshal(u)
-        if err != nil {
-            return err
-        }
-
-        // Persist bytes to users bucket.
-        return b.Put(itob(u.ID), buf)
-    })
-}
-
-// itob returns an 8-byte big endian representation of v.
-func itob(v int) []byte {
-    b := make([]byte, 8)
-    binary.BigEndian.PutUint64(b, uint64(v))
-    return b
-}
-
-type User struct {
-    ID int
-    ...
-}
-```
-
-### Iterating over keys
-
-Bolt stores its keys in byte-sorted order within a bucket. This makes sequential
-iteration over these keys extremely fast. To iterate over keys we'll use a
-`Cursor`:
-
-```go
-db.View(func(tx *bolt.Tx) error {
-	// Assume bucket exists and has keys
-	b := tx.Bucket([]byte("MyBucket"))
-
-	c := b.Cursor()
-
-	for k, v := c.First(); k != nil; k, v = c.Next() {
-		fmt.Printf("key=%s, value=%s\n", k, v)
-	}
-
-	return nil
-})
-```
-
-The cursor allows you to move to a specific point in the list of keys and move
-forward or backward through the keys one at a time.
-
-The following functions are available on the cursor:
-
-```
-First()  Move to the first key.
-Last()   Move to the last key.
-Seek()   Move to a specific key.
-Next()   Move to the next key.
-Prev()   Move to the previous key.
-```
-
-Each of those functions has a return signature of `(key []byte, value []byte)`.
-When you have iterated to the end of the cursor then `Next()` will return a
-`nil` key.  You must seek to a position using `First()`, `Last()`, or `Seek()`
-before calling `Next()` or `Prev()`. If you do not seek to a position then
-these functions will return a `nil` key.
-
-During iteration, if the key is non-`nil` but the value is `nil`, that means
-the key refers to a bucket rather than a value.  Use `Bucket.Bucket()` to
-access the sub-bucket.
-
-
-#### Prefix scans
-
-To iterate over a key prefix, you can combine `Seek()` and `bytes.HasPrefix()`:
-
-```go
-db.View(func(tx *bolt.Tx) error {
-	// Assume bucket exists and has keys
-	c := tx.Bucket([]byte("MyBucket")).Cursor()
-
-	prefix := []byte("1234")
-	for k, v := c.Seek(prefix); k != nil && bytes.HasPrefix(k, prefix); k, v = c.Next() {
-		fmt.Printf("key=%s, value=%s\n", k, v)
-	}
-
-	return nil
-})
-```
-
-#### Range scans
-
-Another common use case is scanning over a range such as a time range. If you
-use a sortable time encoding such as RFC3339 then you can query a specific
-date range like this:
-
-```go
-db.View(func(tx *bolt.Tx) error {
-	// Assume our events bucket exists and has RFC3339 encoded time keys.
-	c := tx.Bucket([]byte("Events")).Cursor()
-
-	// Our time range spans the 90's decade.
-	min := []byte("1990-01-01T00:00:00Z")
-	max := []byte("2000-01-01T00:00:00Z")
-
-	// Iterate over the 90's.
-	for k, v := c.Seek(min); k != nil && bytes.Compare(k, max) <= 0; k, v = c.Next() {
-		fmt.Printf("%s: %s\n", k, v)
-	}
-
-	return nil
-})
-```
-
-Note that, while RFC3339 is sortable, the Golang implementation of RFC3339Nano does not use a fixed number of digits after the decimal point and is therefore not sortable.
-
-
-#### ForEach()
-
-You can also use the function `ForEach()` if you know you'll be iterating over
-all the keys in a bucket:
-
-```go
-db.View(func(tx *bolt.Tx) error {
-	// Assume bucket exists and has keys
-	b := tx.Bucket([]byte("MyBucket"))
-
-	b.ForEach(func(k, v []byte) error {
-		fmt.Printf("key=%s, value=%s\n", k, v)
-		return nil
-	})
-	return nil
-})
-```
-
-Please note that keys and values in `ForEach()` are only valid while
-the transaction is open. If you need to use a key or value outside of
-the transaction, you must use `copy()` to copy it to another byte
-slice.
-
-### Nested buckets
-
-You can also store a bucket in a key to create nested buckets. The API is the
-same as the bucket management API on the `DB` object:
-
-```go
-func (*Bucket) CreateBucket(key []byte) (*Bucket, error)
-func (*Bucket) CreateBucketIfNotExists(key []byte) (*Bucket, error)
-func (*Bucket) DeleteBucket(key []byte) error
-```
-
-Say you had a multi-tenant application where the root level bucket was the account bucket. Inside of this bucket was a sequence of accounts which themselves are buckets. And inside the sequence bucket you could have many buckets pertaining to the Account itself (Users, Notes, etc) isolating the information into logical groupings.
-
-```go
-
-// createUser creates a new user in the given account.
-func createUser(accountID int, u *User) error {
-    // Start the transaction.
-    tx, err := db.Begin(true)
-    if err != nil {
-        return err
-    }
-    defer tx.Rollback()
-
-    // Retrieve the root bucket for the account.
-    // Assume this has already been created when the account was set up.
-    root := tx.Bucket([]byte(strconv.FormatUint(accountID, 10)))
-
-    // Setup the users bucket.
-    bkt, err := root.CreateBucketIfNotExists([]byte("USERS"))
-    if err != nil {
-        return err
-    }
-
-    // Generate an ID for the new user.
-    userID, err := bkt.NextSequence()
-    if err != nil {
-        return err
-    }
-    u.ID = userID
-
-    // Marshal and save the encoded user.
-    if buf, err := json.Marshal(u); err != nil {
-        return err
-    } else if err := bkt.Put([]byte(strconv.FormatUint(u.ID, 10)), buf); err != nil {
-        return err
-    }
-
-    // Commit the transaction.
-    if err := tx.Commit(); err != nil {
-        return err
-    }
-
-    return nil
-}
-
-```
-
-
-
-
-### Database backups
-
-Bolt is a single file so it's easy to backup. You can use the `Tx.WriteTo()`
-function to write a consistent view of the database to a writer. If you call
-this from a read-only transaction, it will perform a hot backup and not block
-your other database reads and writes.
-
-By default, it will use a regular file handle which will utilize the operating
-system's page cache. See the [`Tx`](https://godoc.org/go.etcd.io/bbolt#Tx)
-documentation for information about optimizing for larger-than-RAM datasets.
-
-One common use case is to backup over HTTP so you can use tools like `cURL` to
-do database backups:
-
-```go
-func BackupHandleFunc(w http.ResponseWriter, req *http.Request) {
-	err := db.View(func(tx *bolt.Tx) error {
-		w.Header().Set("Content-Type", "application/octet-stream")
-		w.Header().Set("Content-Disposition", `attachment; filename="my.db"`)
-		w.Header().Set("Content-Length", strconv.Itoa(int(tx.Size())))
-		_, err := tx.WriteTo(w)
-		return err
-	})
-	if err != nil {
-		http.Error(w, err.Error(), http.StatusInternalServerError)
-	}
-}
-```
-
-Then you can backup using this command:
-
-```sh
-$ curl http://localhost/backup > my.db
-```
-
-Or you can open your browser to `http://localhost/backup` and it will download
-automatically.
-
-If you want to backup to another file you can use the `Tx.CopyFile()` helper
-function.
-
-
-### Statistics
-
-The database keeps a running count of many of the internal operations it
-performs so you can better understand what's going on. By grabbing a snapshot
-of these stats at two points in time we can see what operations were performed
-in that time range.
-
-For example, we could start a goroutine to log stats every 10 seconds:
-
-```go
-go func() {
-	// Grab the initial stats.
-	prev := db.Stats()
-
-	for {
-		// Wait for 10s.
-		time.Sleep(10 * time.Second)
-
-		// Grab the current stats and diff them.
-		stats := db.Stats()
-		diff := stats.Sub(&prev)
-
-		// Encode stats to JSON and print to STDERR.
-		json.NewEncoder(os.Stderr).Encode(diff)
-
-		// Save stats for the next loop.
-		prev = stats
-	}
-}()
-```
-
-It's also useful to pipe these stats to a service such as statsd for monitoring
-or to provide an HTTP endpoint that will perform a fixed-length sample.
-
-
-### Read-Only Mode
-
-Sometimes it is useful to create a shared, read-only Bolt database. To this,
-set the `Options.ReadOnly` flag when opening your database. Read-only mode
-uses a shared lock to allow multiple processes to read from the database but
-it will block any processes from opening the database in read-write mode.
-
-```go
-db, err := bolt.Open("my.db", 0666, &bolt.Options{ReadOnly: true})
-if err != nil {
-	log.Fatal(err)
-}
-```
-
-### Mobile Use (iOS/Android)
-
-Bolt is able to run on mobile devices by leveraging the binding feature of the
-[gomobile](https://github.com/golang/mobile) tool. Create a struct that will
-contain your database logic and a reference to a `*bolt.DB` with a initializing
-constructor that takes in a filepath where the database file will be stored.
-Neither Android nor iOS require extra permissions or cleanup from using this method.
-
-```go
-func NewBoltDB(filepath string) *BoltDB {
-	db, err := bolt.Open(filepath+"/demo.db", 0600, nil)
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	return &BoltDB{db}
-}
-
-type BoltDB struct {
-	db *bolt.DB
-	...
-}
-
-func (b *BoltDB) Path() string {
-	return b.db.Path()
-}
-
-func (b *BoltDB) Close() {
-	b.db.Close()
-}
-```
-
-Database logic should be defined as methods on this wrapper struct.
-
-To initialize this struct from the native language (both platforms now sync
-their local storage to the cloud. These snippets disable that functionality for the
-database file):
-
-#### Android
-
-```java
-String path;
-if (android.os.Build.VERSION.SDK_INT >=android.os.Build.VERSION_CODES.LOLLIPOP){
-    path = getNoBackupFilesDir().getAbsolutePath();
-} else{
-    path = getFilesDir().getAbsolutePath();
-}
-Boltmobiledemo.BoltDB boltDB = Boltmobiledemo.NewBoltDB(path)
-```
-
-#### iOS
-
-```objc
-- (void)demo {
-    NSString* path = [NSSearchPathForDirectoriesInDomains(NSLibraryDirectory,
-                                                          NSUserDomainMask,
-                                                          YES) objectAtIndex:0];
-	GoBoltmobiledemoBoltDB * demo = GoBoltmobiledemoNewBoltDB(path);
-	[self addSkipBackupAttributeToItemAtPath:demo.path];
-	//Some DB Logic would go here
-	[demo close];
-}
-
-- (BOOL)addSkipBackupAttributeToItemAtPath:(NSString *) filePathString
-{
-    NSURL* URL= [NSURL fileURLWithPath: filePathString];
-    assert([[NSFileManager defaultManager] fileExistsAtPath: [URL path]]);
-
-    NSError *error = nil;
-    BOOL success = [URL setResourceValue: [NSNumber numberWithBool: YES]
-                                  forKey: NSURLIsExcludedFromBackupKey error: &error];
-    if(!success){
-        NSLog(@"Error excluding %@ from backup %@", [URL lastPathComponent], error);
-    }
-    return success;
-}
-
-```
-
-## Resources
-
-For more information on getting started with Bolt, check out the following articles:
-
-* [Intro to BoltDB: Painless Performant Persistence](http://npf.io/2014/07/intro-to-boltdb-painless-performant-persistence/) by [Nate Finch](https://github.com/natefinch).
-* [Bolt -- an embedded key/value database for Go](https://www.progville.com/go/bolt-embedded-db-golang/) by Progville
-
-
-## Comparison with other databases
-
-### Postgres, MySQL, & other relational databases
-
-Relational databases structure data into rows and are only accessible through
-the use of SQL. This approach provides flexibility in how you store and query
-your data but also incurs overhead in parsing and planning SQL statements. Bolt
-accesses all data by a byte slice key. This makes Bolt fast to read and write
-data by key but provides no built-in support for joining values together.
-
-Most relational databases (with the exception of SQLite) are standalone servers
-that run separately from your application. This gives your systems
-flexibility to connect multiple application servers to a single database
-server but also adds overhead in serializing and transporting data over the
-network. Bolt runs as a library included in your application so all data access
-has to go through your application's process. This brings data closer to your
-application but limits multi-process access to the data.
-
-
-### LevelDB, RocksDB
-
-LevelDB and its derivatives (RocksDB, HyperLevelDB) are similar to Bolt in that
-they are libraries bundled into the application, however, their underlying
-structure is a log-structured merge-tree (LSM tree). An LSM tree optimizes
-random writes by using a write ahead log and multi-tiered, sorted files called
-SSTables. Bolt uses a B+tree internally and only a single file. Both approaches
-have trade-offs.
-
-If you require a high random write throughput (>10,000 w/sec) or you need to use
-spinning disks then LevelDB could be a good choice. If your application is
-read-heavy or does a lot of range scans then Bolt could be a good choice.
-
-One other important consideration is that LevelDB does not have transactions.
-It supports batch writing of key/values pairs and it supports read snapshots
-but it will not give you the ability to do a compare-and-swap operation safely.
-Bolt supports fully serializable ACID transactions.
-
-
-### LMDB
-
-Bolt was originally a port of LMDB so it is architecturally similar. Both use
-a B+tree, have ACID semantics with fully serializable transactions, and support
-lock-free MVCC using a single writer and multiple readers.
-
-The two projects have somewhat diverged. LMDB heavily focuses on raw performance
-while Bolt has focused on simplicity and ease of use. For example, LMDB allows
-several unsafe actions such as direct writes for the sake of performance. Bolt
-opts to disallow actions which can leave the database in a corrupted state. The
-only exception to this in Bolt is `DB.NoSync`.
-
-There are also a few differences in API. LMDB requires a maximum mmap size when
-opening an `mdb_env` whereas Bolt will handle incremental mmap resizing
-automatically. LMDB overloads the getter and setter functions with multiple
-flags whereas Bolt splits these specialized cases into their own functions.
-
-
-## Caveats & Limitations
-
-It's important to pick the right tool for the job and Bolt is no exception.
-Here are a few things to note when evaluating and using Bolt:
-
-* Bolt is good for read intensive workloads. Sequential write performance is
-  also fast but random writes can be slow. You can use `DB.Batch()` or add a
-  write-ahead log to help mitigate this issue.
-
-* Bolt uses a B+tree internally so there can be a lot of random page access.
-  SSDs provide a significant performance boost over spinning disks.
-
-* Try to avoid long running read transactions. Bolt uses copy-on-write so
-  old pages cannot be reclaimed while an old transaction is using them.
-
-* Byte slices returned from Bolt are only valid during a transaction. Once the
-  transaction has been committed or rolled back then the memory they point to
-  can be reused by a new page or can be unmapped from virtual memory and you'll
-  see an `unexpected fault address` panic when accessing it.
-
-* Bolt uses an exclusive write lock on the database file so it cannot be
-  shared by multiple processes.
-
-* Be careful when using `Bucket.FillPercent`. Setting a high fill percent for
-  buckets that have random inserts will cause your database to have very poor
-  page utilization.
-
-* Use larger buckets in general. Smaller buckets causes poor page utilization
-  once they become larger than the page size (typically 4KB).
-
-* Bulk loading a lot of random writes into a new bucket can be slow as the
-  page will not split until the transaction is committed. Randomly inserting
-  more than 100,000 key/value pairs into a single new bucket in a single
-  transaction is not advised.
-
-* Bolt uses a memory-mapped file so the underlying operating system handles the
-  caching of the data. Typically, the OS will cache as much of the file as it
-  can in memory and will release memory as needed to other processes. This means
-  that Bolt can show very high memory usage when working with large databases.
-  However, this is expected and the OS will release memory as needed. Bolt can
-  handle databases much larger than the available physical RAM, provided its
-  memory-map fits in the process virtual address space. It may be problematic
-  on 32-bits systems.
-
-* The data structures in the Bolt database are memory mapped so the data file
-  will be endian specific. This means that you cannot copy a Bolt file from a
-  little endian machine to a big endian machine and have it work. For most
-  users this is not a concern since most modern CPUs are little endian.
-
-* Because of the way pages are laid out on disk, Bolt cannot truncate data files
-  and return free pages back to the disk. Instead, Bolt maintains a free list
-  of unused pages within its data file. These free pages can be reused by later
-  transactions. This works well for many use cases as databases generally tend
-  to grow. However, it's important to note that deleting large chunks of data
-  will not allow you to reclaim that space on disk.
-
-  For more information on page allocation, [see this comment][page-allocation].
-
-[page-allocation]: https://github.com/boltdb/bolt/issues/308#issuecomment-74811638
-
-
-## Reading the Source
-
-Bolt is a relatively small code base (<5KLOC) for an embedded, serializable,
-transactional key/value database so it can be a good starting point for people
-interested in how databases work.
-
-The best places to start are the main entry points into Bolt:
-
-- `Open()` - Initializes the reference to the database. It's responsible for
-  creating the database if it doesn't exist, obtaining an exclusive lock on the
-  file, reading the meta pages, & memory-mapping the file.
-
-- `DB.Begin()` - Starts a read-only or read-write transaction depending on the
-  value of the `writable` argument. This requires briefly obtaining the "meta"
-  lock to keep track of open transactions. Only one read-write transaction can
-  exist at a time so the "rwlock" is acquired during the life of a read-write
-  transaction.
-
-- `Bucket.Put()` - Writes a key/value pair into a bucket. After validating the
-  arguments, a cursor is used to traverse the B+tree to the page and position
-  where they key & value will be written. Once the position is found, the bucket
-  materializes the underlying page and the page's parent pages into memory as
-  "nodes". These nodes are where mutations occur during read-write transactions.
-  These changes get flushed to disk during commit.
-
-- `Bucket.Get()` - Retrieves a key/value pair from a bucket. This uses a cursor
-  to move to the page & position of a key/value pair. During a read-only
-  transaction, the key and value data is returned as a direct reference to the
-  underlying mmap file so there's no allocation overhead. For read-write
-  transactions, this data may reference the mmap file or one of the in-memory
-  node values.
-
-- `Cursor` - This object is simply for traversing the B+tree of on-disk pages
-  or in-memory nodes. It can seek to a specific key, move to the first or last
-  value, or it can move forward or backward. The cursor handles the movement up
-  and down the B+tree transparently to the end user.
-
-- `Tx.Commit()` - Converts the in-memory dirty nodes and the list of free pages
-  into pages to be written to disk. Writing to disk then occurs in two phases.
-  First, the dirty pages are written to disk and an `fsync()` occurs. Second, a
-  new meta page with an incremented transaction ID is written and another
-  `fsync()` occurs. This two phase write ensures that partially written data
-  pages are ignored in the event of a crash since the meta page pointing to them
-  is never written. Partially written meta pages are invalidated because they
-  are written with a checksum.
-
-If you have additional notes that could be helpful for others, please submit
-them via pull request.
-
-
-## Other Projects Using Bolt
-
-Below is a list of public, open source projects that use Bolt:
-
-* [Algernon](https://github.com/xyproto/algernon) - A HTTP/2 web server with built-in support for Lua. Uses BoltDB as the default database backend.
-* [Bazil](https://bazil.org/) - A file system that lets your data reside where it is most convenient for it to reside.
-* [bolter](https://github.com/hasit/bolter) - Command-line app for viewing BoltDB file in your terminal.
-* [boltcli](https://github.com/spacewander/boltcli) - the redis-cli for boltdb with Lua script support.
-* [BoltHold](https://github.com/timshannon/bolthold) - An embeddable NoSQL store for Go types built on BoltDB
-* [BoltStore](https://github.com/yosssi/boltstore) - Session store using Bolt.
-* [Boltdb Boilerplate](https://github.com/bobintornado/boltdb-boilerplate) - Boilerplate wrapper around bolt aiming to make simple calls one-liners.
-* [BoltDbWeb](https://github.com/evnix/boltdbweb) - A web based GUI for BoltDB files.
-* [bleve](http://www.blevesearch.com/) - A pure Go search engine similar to ElasticSearch that uses Bolt as the default storage backend.
-* [btcwallet](https://github.com/btcsuite/btcwallet) - A bitcoin wallet.
-* [buckets](https://github.com/joyrexus/buckets) - a bolt wrapper streamlining
-  simple tx and key scans.
-* [cayley](https://github.com/google/cayley) - Cayley is an open-source graph database using Bolt as optional backend.
-* [ChainStore](https://github.com/pressly/chainstore) - Simple key-value interface to a variety of storage engines organized as a chain of operations.
-* [Consul](https://github.com/hashicorp/consul) - Consul is service discovery and configuration made easy. Distributed, highly available, and datacenter-aware.
-* [DVID](https://github.com/janelia-flyem/dvid) - Added Bolt as optional storage engine and testing it against Basho-tuned leveldb.
-* [dcrwallet](https://github.com/decred/dcrwallet) - A wallet for the Decred cryptocurrency.
-* [drive](https://github.com/odeke-em/drive) - drive is an unofficial Google Drive command line client for \*NIX operating systems.
-* [event-shuttle](https://github.com/sclasen/event-shuttle) - A Unix system service to collect and reliably deliver messages to Kafka.
-* [Freehold](http://tshannon.bitbucket.org/freehold/) - An open, secure, and lightweight platform for your files and data.
-* [Go Report Card](https://goreportcard.com/) - Go code quality report cards as a (free and open source) service.
-* [GoWebApp](https://github.com/josephspurrier/gowebapp) - A basic MVC web application in Go using BoltDB.
-* [GoShort](https://github.com/pankajkhairnar/goShort) - GoShort is a URL shortener written in Golang and BoltDB for persistent key/value storage and for routing it's using high performent HTTPRouter.
-* [gopherpit](https://github.com/gopherpit/gopherpit) - A web service to manage Go remote import paths with custom domains
-* [Gitchain](https://github.com/gitchain/gitchain) - Decentralized, peer-to-peer Git repositories aka "Git meets Bitcoin".
-* [InfluxDB](https://influxdata.com) - Scalable datastore for metrics, events, and real-time analytics.
-* [ipLocator](https://github.com/AndreasBriese/ipLocator) - A fast ip-geo-location-server using bolt with bloom filters.
-* [ipxed](https://github.com/kelseyhightower/ipxed) - Web interface and api for ipxed.
-* [Ironsmith](https://github.com/timshannon/ironsmith) - A simple, script-driven continuous integration (build - > test -> release) tool, with no external dependencies
-* [Kala](https://github.com/ajvb/kala) - Kala is a modern job scheduler optimized to run on a single node. It is persistent, JSON over HTTP API, ISO 8601 duration notation, and dependent jobs.
-* [Key Value Access Langusge (KVAL)](https://github.com/kval-access-language) - A proposed grammar for key-value datastores offering a bbolt binding.
-* [LedisDB](https://github.com/siddontang/ledisdb) - A high performance NoSQL, using Bolt as optional storage.
-* [lru](https://github.com/crowdriff/lru) - Easy to use Bolt-backed Least-Recently-Used (LRU) read-through cache with chainable remote stores.
-* [mbuckets](https://github.com/abhigupta912/mbuckets) - A Bolt wrapper that allows easy operations on multi level (nested) buckets.
-* [MetricBase](https://github.com/msiebuhr/MetricBase) - Single-binary version of Graphite.
-* [MuLiFS](https://github.com/dankomiocevic/mulifs) - Music Library Filesystem creates a filesystem to organise your music files.
-* [Operation Go: A Routine Mission](http://gocode.io) - An online programming game for Golang using Bolt for user accounts and a leaderboard.
-* [photosite/session](https://godoc.org/bitbucket.org/kardianos/photosite/session) - Sessions for a photo viewing site.
-* [Prometheus Annotation Server](https://github.com/oliver006/prom_annotation_server) - Annotation server for PromDash & Prometheus service monitoring system.
-* [reef-pi](https://github.com/reef-pi/reef-pi) - reef-pi is an award winning, modular, DIY reef tank controller using easy to learn electronics based on a Raspberry Pi.
-* [Request Baskets](https://github.com/darklynx/request-baskets) - A web service to collect arbitrary HTTP requests and inspect them via REST API or simple web UI, similar to [RequestBin](http://requestb.in/) service
-* [Seaweed File System](https://github.com/chrislusf/seaweedfs) - Highly scalable distributed key~file system with O(1) disk read.
-* [stow](https://github.com/djherbis/stow) -  a persistence manager for objects
-  backed by boltdb.
-* [Storm](https://github.com/asdine/storm) - Simple and powerful ORM for BoltDB.
-* [SimpleBolt](https://github.com/xyproto/simplebolt) - A simple way to use BoltDB. Deals mainly with strings.
-* [Skybox Analytics](https://github.com/skybox/skybox) - A standalone funnel analysis tool for web analytics.
-* [Scuttlebutt](https://github.com/benbjohnson/scuttlebutt) - Uses Bolt to store and process all Twitter mentions of GitHub projects.
-* [tentacool](https://github.com/optiflows/tentacool) - REST api server to manage system stuff (IP, DNS, Gateway...) on a linux server.
-* [torrent](https://github.com/anacrolix/torrent) - Full-featured BitTorrent client package and utilities in Go. BoltDB is a storage backend in development.
-* [Wiki](https://github.com/peterhellberg/wiki) - A tiny wiki using Goji, BoltDB and Blackfriday.
-
-If you are using Bolt in a project please send a pull request to add it to the list.
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_386.go b/vendor/github.com/etcd-io/bbolt/bolt_386.go
deleted file mode 100644
index 4d35ee7cf3..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_386.go
+++ /dev/null
@@ -1,10 +0,0 @@
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0x7FFFFFFF // 2GB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0xFFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_amd64.go b/vendor/github.com/etcd-io/bbolt/bolt_amd64.go
deleted file mode 100644
index 60a52dad56..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_amd64.go
+++ /dev/null
@@ -1,10 +0,0 @@
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_arm.go b/vendor/github.com/etcd-io/bbolt/bolt_arm.go
deleted file mode 100644
index 105d27ddb7..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_arm.go
+++ /dev/null
@@ -1,28 +0,0 @@
-package bbolt
-
-import "unsafe"
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0x7FFFFFFF // 2GB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0xFFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned bool
-
-func init() {
-	// Simple check to see whether this arch handles unaligned load/stores
-	// correctly.
-
-	// ARM9 and older devices require load/stores to be from/to aligned
-	// addresses. If not, the lower 2 bits are cleared and that address is
-	// read in a jumbled up order.
-
-	// See http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka15414.html
-
-	raw := [6]byte{0xfe, 0xef, 0x11, 0x22, 0x22, 0x11}
-	val := *(*uint32)(unsafe.Pointer(uintptr(unsafe.Pointer(&raw)) + 2))
-
-	brokenUnaligned = val != 0x11222211
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_arm64.go b/vendor/github.com/etcd-io/bbolt/bolt_arm64.go
deleted file mode 100644
index f5aa2a5ee2..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_arm64.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build arm64
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_linux.go b/vendor/github.com/etcd-io/bbolt/bolt_linux.go
deleted file mode 100644
index 7707bcacf0..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_linux.go
+++ /dev/null
@@ -1,10 +0,0 @@
-package bbolt
-
-import (
-	"syscall"
-)
-
-// fdatasync flushes written data to a file descriptor.
-func fdatasync(db *DB) error {
-	return syscall.Fdatasync(int(db.file.Fd()))
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_mips64x.go b/vendor/github.com/etcd-io/bbolt/bolt_mips64x.go
deleted file mode 100644
index baeb289fd9..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_mips64x.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build mips64 mips64le
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0x8000000000 // 512GB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_mipsx.go b/vendor/github.com/etcd-io/bbolt/bolt_mipsx.go
deleted file mode 100644
index 2d9b1a91f3..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_mipsx.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build mips mipsle
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0x40000000 // 1GB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0xFFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_openbsd.go b/vendor/github.com/etcd-io/bbolt/bolt_openbsd.go
deleted file mode 100644
index d7f50358ef..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_openbsd.go
+++ /dev/null
@@ -1,27 +0,0 @@
-package bbolt
-
-import (
-	"syscall"
-	"unsafe"
-)
-
-const (
-	msAsync      = 1 << iota // perform asynchronous writes
-	msSync                   // perform synchronous writes
-	msInvalidate             // invalidate cached data
-)
-
-func msync(db *DB) error {
-	_, _, errno := syscall.Syscall(syscall.SYS_MSYNC, uintptr(unsafe.Pointer(db.data)), uintptr(db.datasz), msInvalidate)
-	if errno != 0 {
-		return errno
-	}
-	return nil
-}
-
-func fdatasync(db *DB) error {
-	if db.data != nil {
-		return msync(db)
-	}
-	return db.file.Sync()
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_ppc.go b/vendor/github.com/etcd-io/bbolt/bolt_ppc.go
deleted file mode 100644
index 69804714aa..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_ppc.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build ppc
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0x7FFFFFFF // 2GB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0xFFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_ppc64.go b/vendor/github.com/etcd-io/bbolt/bolt_ppc64.go
deleted file mode 100644
index 3565908576..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_ppc64.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build ppc64
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_ppc64le.go b/vendor/github.com/etcd-io/bbolt/bolt_ppc64le.go
deleted file mode 100644
index 422c7c69d6..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_ppc64le.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build ppc64le
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_riscv64.go b/vendor/github.com/etcd-io/bbolt/bolt_riscv64.go
deleted file mode 100644
index 07b4b47cdb..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_riscv64.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build riscv64
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = true
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_s390x.go b/vendor/github.com/etcd-io/bbolt/bolt_s390x.go
deleted file mode 100644
index 6d3fcb825d..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_s390x.go
+++ /dev/null
@@ -1,12 +0,0 @@
-// +build s390x
-
-package bbolt
-
-// maxMapSize represents the largest mmap size supported by Bolt.
-const maxMapSize = 0xFFFFFFFFFFFF // 256TB
-
-// maxAllocSize is the size used when creating array pointers.
-const maxAllocSize = 0x7FFFFFFF
-
-// Are unaligned load/stores broken on this arch?
-var brokenUnaligned = false
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_unix.go b/vendor/github.com/etcd-io/bbolt/bolt_unix.go
deleted file mode 100644
index 5f2bb51451..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_unix.go
+++ /dev/null
@@ -1,93 +0,0 @@
-// +build !windows,!plan9,!solaris
-
-package bbolt
-
-import (
-	"fmt"
-	"syscall"
-	"time"
-	"unsafe"
-)
-
-// flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, exclusive bool, timeout time.Duration) error {
-	var t time.Time
-	if timeout != 0 {
-		t = time.Now()
-	}
-	fd := db.file.Fd()
-	flag := syscall.LOCK_NB
-	if exclusive {
-		flag |= syscall.LOCK_EX
-	} else {
-		flag |= syscall.LOCK_SH
-	}
-	for {
-		// Attempt to obtain an exclusive lock.
-		err := syscall.Flock(int(fd), flag)
-		if err == nil {
-			return nil
-		} else if err != syscall.EWOULDBLOCK {
-			return err
-		}
-
-		// If we timed out then return an error.
-		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
-			return ErrTimeout
-		}
-
-		// Wait for a bit and try again.
-		time.Sleep(flockRetryTimeout)
-	}
-}
-
-// funlock releases an advisory lock on a file descriptor.
-func funlock(db *DB) error {
-	return syscall.Flock(int(db.file.Fd()), syscall.LOCK_UN)
-}
-
-// mmap memory maps a DB's data file.
-func mmap(db *DB, sz int) error {
-	// Map the data file to memory.
-	b, err := syscall.Mmap(int(db.file.Fd()), 0, sz, syscall.PROT_READ, syscall.MAP_SHARED|db.MmapFlags)
-	if err != nil {
-		return err
-	}
-
-	// Advise the kernel that the mmap is accessed randomly.
-	err = madvise(b, syscall.MADV_RANDOM)
-	if err != nil && err != syscall.ENOSYS {
-		// Ignore not implemented error in kernel because it still works.
-		return fmt.Errorf("madvise: %s", err)
-	}
-
-	// Save the original byte slice and convert to a byte array pointer.
-	db.dataref = b
-	db.data = (*[maxMapSize]byte)(unsafe.Pointer(&b[0]))
-	db.datasz = sz
-	return nil
-}
-
-// munmap unmaps a DB's data file from memory.
-func munmap(db *DB) error {
-	// Ignore the unmap if we have no mapped data.
-	if db.dataref == nil {
-		return nil
-	}
-
-	// Unmap using the original byte slice.
-	err := syscall.Munmap(db.dataref)
-	db.dataref = nil
-	db.data = nil
-	db.datasz = 0
-	return err
-}
-
-// NOTE: This function is copied from stdlib because it is not available on darwin.
-func madvise(b []byte, advice int) (err error) {
-	_, _, e1 := syscall.Syscall(syscall.SYS_MADVISE, uintptr(unsafe.Pointer(&b[0])), uintptr(len(b)), uintptr(advice))
-	if e1 != 0 {
-		err = e1
-	}
-	return
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_unix_solaris.go b/vendor/github.com/etcd-io/bbolt/bolt_unix_solaris.go
deleted file mode 100644
index babad65786..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_unix_solaris.go
+++ /dev/null
@@ -1,88 +0,0 @@
-package bbolt
-
-import (
-	"fmt"
-	"syscall"
-	"time"
-	"unsafe"
-
-	"golang.org/x/sys/unix"
-)
-
-// flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, exclusive bool, timeout time.Duration) error {
-	var t time.Time
-	if timeout != 0 {
-		t = time.Now()
-	}
-	fd := db.file.Fd()
-	var lockType int16
-	if exclusive {
-		lockType = syscall.F_WRLCK
-	} else {
-		lockType = syscall.F_RDLCK
-	}
-	for {
-		// Attempt to obtain an exclusive lock.
-		lock := syscall.Flock_t{Type: lockType}
-		err := syscall.FcntlFlock(fd, syscall.F_SETLK, &lock)
-		if err == nil {
-			return nil
-		} else if err != syscall.EAGAIN {
-			return err
-		}
-
-		// If we timed out then return an error.
-		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
-			return ErrTimeout
-		}
-
-		// Wait for a bit and try again.
-		time.Sleep(flockRetryTimeout)
-	}
-}
-
-// funlock releases an advisory lock on a file descriptor.
-func funlock(db *DB) error {
-	var lock syscall.Flock_t
-	lock.Start = 0
-	lock.Len = 0
-	lock.Type = syscall.F_UNLCK
-	lock.Whence = 0
-	return syscall.FcntlFlock(uintptr(db.file.Fd()), syscall.F_SETLK, &lock)
-}
-
-// mmap memory maps a DB's data file.
-func mmap(db *DB, sz int) error {
-	// Map the data file to memory.
-	b, err := unix.Mmap(int(db.file.Fd()), 0, sz, syscall.PROT_READ, syscall.MAP_SHARED|db.MmapFlags)
-	if err != nil {
-		return err
-	}
-
-	// Advise the kernel that the mmap is accessed randomly.
-	if err := unix.Madvise(b, syscall.MADV_RANDOM); err != nil {
-		return fmt.Errorf("madvise: %s", err)
-	}
-
-	// Save the original byte slice and convert to a byte array pointer.
-	db.dataref = b
-	db.data = (*[maxMapSize]byte)(unsafe.Pointer(&b[0]))
-	db.datasz = sz
-	return nil
-}
-
-// munmap unmaps a DB's data file from memory.
-func munmap(db *DB) error {
-	// Ignore the unmap if we have no mapped data.
-	if db.dataref == nil {
-		return nil
-	}
-
-	// Unmap using the original byte slice.
-	err := unix.Munmap(db.dataref)
-	db.dataref = nil
-	db.data = nil
-	db.datasz = 0
-	return err
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bolt_windows.go b/vendor/github.com/etcd-io/bbolt/bolt_windows.go
deleted file mode 100644
index fca178bd29..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bolt_windows.go
+++ /dev/null
@@ -1,141 +0,0 @@
-package bbolt
-
-import (
-	"fmt"
-	"os"
-	"syscall"
-	"time"
-	"unsafe"
-)
-
-// LockFileEx code derived from golang build filemutex_windows.go @ v1.5.1
-var (
-	modkernel32      = syscall.NewLazyDLL("kernel32.dll")
-	procLockFileEx   = modkernel32.NewProc("LockFileEx")
-	procUnlockFileEx = modkernel32.NewProc("UnlockFileEx")
-)
-
-const (
-	// see https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
-	flagLockExclusive       = 2
-	flagLockFailImmediately = 1
-
-	// see https://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx
-	errLockViolation syscall.Errno = 0x21
-)
-
-func lockFileEx(h syscall.Handle, flags, reserved, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
-	r, _, err := procLockFileEx.Call(uintptr(h), uintptr(flags), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)))
-	if r == 0 {
-		return err
-	}
-	return nil
-}
-
-func unlockFileEx(h syscall.Handle, reserved, locklow, lockhigh uint32, ol *syscall.Overlapped) (err error) {
-	r, _, err := procUnlockFileEx.Call(uintptr(h), uintptr(reserved), uintptr(locklow), uintptr(lockhigh), uintptr(unsafe.Pointer(ol)), 0)
-	if r == 0 {
-		return err
-	}
-	return nil
-}
-
-// fdatasync flushes written data to a file descriptor.
-func fdatasync(db *DB) error {
-	return db.file.Sync()
-}
-
-// flock acquires an advisory lock on a file descriptor.
-func flock(db *DB, exclusive bool, timeout time.Duration) error {
-	var t time.Time
-	if timeout != 0 {
-		t = time.Now()
-	}
-	var flag uint32 = flagLockFailImmediately
-	if exclusive {
-		flag |= flagLockExclusive
-	}
-	for {
-		// Fix for https://github.com/etcd-io/bbolt/issues/121. Use byte-range
-		// -1..0 as the lock on the database file.
-		var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
-		err := lockFileEx(syscall.Handle(db.file.Fd()), flag, 0, 1, 0, &syscall.Overlapped{
-			Offset:     m1,
-			OffsetHigh: m1,
-		})
-
-		if err == nil {
-			return nil
-		} else if err != errLockViolation {
-			return err
-		}
-
-		// If we timed oumercit then return an error.
-		if timeout != 0 && time.Since(t) > timeout-flockRetryTimeout {
-			return ErrTimeout
-		}
-
-		// Wait for a bit and try again.
-		time.Sleep(flockRetryTimeout)
-	}
-}
-
-// funlock releases an advisory lock on a file descriptor.
-func funlock(db *DB) error {
-	var m1 uint32 = (1 << 32) - 1 // -1 in a uint32
-	err := unlockFileEx(syscall.Handle(db.file.Fd()), 0, 1, 0, &syscall.Overlapped{
-		Offset:     m1,
-		OffsetHigh: m1,
-	})
-	return err
-}
-
-// mmap memory maps a DB's data file.
-// Based on: https://github.com/edsrzf/mmap-go
-func mmap(db *DB, sz int) error {
-	if !db.readOnly {
-		// Truncate the database to the size of the mmap.
-		if err := db.file.Truncate(int64(sz)); err != nil {
-			return fmt.Errorf("truncate: %s", err)
-		}
-	}
-
-	// Open a file mapping handle.
-	sizelo := uint32(sz >> 32)
-	sizehi := uint32(sz) & 0xffffffff
-	h, errno := syscall.CreateFileMapping(syscall.Handle(db.file.Fd()), nil, syscall.PAGE_READONLY, sizelo, sizehi, nil)
-	if h == 0 {
-		return os.NewSyscallError("CreateFileMapping", errno)
-	}
-
-	// Create the memory map.
-	addr, errno := syscall.MapViewOfFile(h, syscall.FILE_MAP_READ, 0, 0, uintptr(sz))
-	if addr == 0 {
-		return os.NewSyscallError("MapViewOfFile", errno)
-	}
-
-	// Close mapping handle.
-	if err := syscall.CloseHandle(syscall.Handle(h)); err != nil {
-		return os.NewSyscallError("CloseHandle", err)
-	}
-
-	// Convert to a byte array.
-	db.data = ((*[maxMapSize]byte)(unsafe.Pointer(addr)))
-	db.datasz = sz
-
-	return nil
-}
-
-// munmap unmaps a pointer from a file.
-// Based on: https://github.com/edsrzf/mmap-go
-func munmap(db *DB) error {
-	if db.data == nil {
-		return nil
-	}
-
-	addr := (uintptr)(unsafe.Pointer(&db.data[0]))
-	if err := syscall.UnmapViewOfFile(addr); err != nil {
-		return os.NewSyscallError("UnmapViewOfFile", err)
-	}
-	return nil
-}
diff --git a/vendor/github.com/etcd-io/bbolt/boltsync_unix.go b/vendor/github.com/etcd-io/bbolt/boltsync_unix.go
deleted file mode 100644
index 9587afefee..0000000000
--- a/vendor/github.com/etcd-io/bbolt/boltsync_unix.go
+++ /dev/null
@@ -1,8 +0,0 @@
-// +build !windows,!plan9,!linux,!openbsd
-
-package bbolt
-
-// fdatasync flushes written data to a file descriptor.
-func fdatasync(db *DB) error {
-	return db.file.Sync()
-}
diff --git a/vendor/github.com/etcd-io/bbolt/bucket.go b/vendor/github.com/etcd-io/bbolt/bucket.go
deleted file mode 100644
index 84bfd4d6a2..0000000000
--- a/vendor/github.com/etcd-io/bbolt/bucket.go
+++ /dev/null
@@ -1,775 +0,0 @@
-package bbolt
-
-import (
-	"bytes"
-	"fmt"
-	"unsafe"
-)
-
-const (
-	// MaxKeySize is the maximum length of a key, in bytes.
-	MaxKeySize = 32768
-
-	// MaxValueSize is the maximum length of a value, in bytes.
-	MaxValueSize = (1 << 31) - 2
-)
-
-const bucketHeaderSize = int(unsafe.Sizeof(bucket{}))
-
-const (
-	minFillPercent = 0.1
-	maxFillPercent = 1.0
-)
-
-// DefaultFillPercent is the percentage that split pages are filled.
-// This value can be changed by setting Bucket.FillPercent.
-const DefaultFillPercent = 0.5
-
-// Bucket represents a collection of key/value pairs inside the database.
-type Bucket struct {
-	*bucket
-	tx       *Tx                // the associated transaction
-	buckets  map[string]*Bucket // subbucket cache
-	page     *page              // inline page reference
-	rootNode *node              // materialized node for the root page.
-	nodes    map[pgid]*node     // node cache
-
-	// Sets the threshold for filling nodes when they split. By default,
-	// the bucket will fill to 50% but it can be useful to increase this
-	// amount if you know that your write workloads are mostly append-only.
-	//
-	// This is non-persisted across transactions so it must be set in every Tx.
-	FillPercent float64
-}
-
-// bucket represents the on-file representation of a bucket.
-// This is stored as the "value" of a bucket key. If the bucket is small enough,
-// then its root page can be stored inline in the "value", after the bucket
-// header. In the case of inline buckets, the "root" will be 0.
-type bucket struct {
-	root     pgid   // page id of the bucket's root-level page
-	sequence uint64 // monotonically incrementing, used by NextSequence()
-}
-
-// newBucket returns a new bucket associated with a transaction.
-func newBucket(tx *Tx) Bucket {
-	var b = Bucket{tx: tx, FillPercent: DefaultFillPercent}
-	if tx.writable {
-		b.buckets = make(map[string]*Bucket)
-		b.nodes = make(map[pgid]*node)
-	}
-	return b
-}
-
-// Tx returns the tx of the bucket.
-func (b *Bucket) Tx() *Tx {
-	return b.tx
-}
-
-// Root returns the root of the bucket.
-func (b *Bucket) Root() pgid {
-	return b.root
-}
-
-// Writable returns whether the bucket is writable.
-func (b *Bucket) Writable() bool {
-	return b.tx.writable
-}
-
-// Cursor creates a cursor associated with the bucket.
-// The cursor is only valid as long as the transaction is open.
-// Do not use a cursor after the transaction is closed.
-func (b *Bucket) Cursor() *Cursor {
-	// Update transaction statistics.
-	b.tx.stats.CursorCount++
-
-	// Allocate and return a cursor.
-	return &Cursor{
-		bucket: b,
-		stack:  make([]elemRef, 0),
-	}
-}
-
-// Bucket retrieves a nested bucket by name.
-// Returns nil if the bucket does not exist.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (b *Bucket) Bucket(name []byte) *Bucket {
-	if b.buckets != nil {
-		if child := b.buckets[string(name)]; child != nil {
-			return child
-		}
-	}
-
-	// Move cursor to key.
-	c := b.Cursor()
-	k, v, flags := c.seek(name)
-
-	// Return nil if the key doesn't exist or it is not a bucket.
-	if !bytes.Equal(name, k) || (flags&bucketLeafFlag) == 0 {
-		return nil
-	}
-
-	// Otherwise create a bucket and cache it.
-	var child = b.openBucket(v)
-	if b.buckets != nil {
-		b.buckets[string(name)] = child
-	}
-
-	return child
-}
-
-// Helper method that re-interprets a sub-bucket value
-// from a parent into a Bucket
-func (b *Bucket) openBucket(value []byte) *Bucket {
-	var child = newBucket(b.tx)
-
-	// If unaligned load/stores are broken on this arch and value is
-	// unaligned simply clone to an aligned byte array.
-	unaligned := brokenUnaligned && uintptr(unsafe.Pointer(&value[0]))&3 != 0
-
-	if unaligned {
-		value = cloneBytes(value)
-	}
-
-	// If this is a writable transaction then we need to copy the bucket entry.
-	// Read-only transactions can point directly at the mmap entry.
-	if b.tx.writable && !unaligned {
-		child.bucket = &bucket{}
-		*child.bucket = *(*bucket)(unsafe.Pointer(&value[0]))
-	} else {
-		child.bucket = (*bucket)(unsafe.Pointer(&value[0]))
-	}
-
-	// Save a reference to the inline page if the bucket is inline.
-	if child.root == 0 {
-		child.page = (*page)(unsafe.Pointer(&value[bucketHeaderSize]))
-	}
-
-	return &child
-}
-
-// CreateBucket creates a new bucket at the given key and returns the new bucket.
-// Returns an error if the key already exists, if the bucket name is blank, or if the bucket name is too long.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (b *Bucket) CreateBucket(key []byte) (*Bucket, error) {
-	if b.tx.db == nil {
-		return nil, ErrTxClosed
-	} else if !b.tx.writable {
-		return nil, ErrTxNotWritable
-	} else if len(key) == 0 {
-		return nil, ErrBucketNameRequired
-	}
-
-	// Move cursor to correct position.
-	c := b.Cursor()
-	k, _, flags := c.seek(key)
-
-	// Return an error if there is an existing key.
-	if bytes.Equal(key, k) {
-		if (flags & bucketLeafFlag) != 0 {
-			return nil, ErrBucketExists
-		}
-		return nil, ErrIncompatibleValue
-	}
-
-	// Create empty, inline bucket.
-	var bucket = Bucket{
-		bucket:      &bucket{},
-		rootNode:    &node{isLeaf: true},
-		FillPercent: DefaultFillPercent,
-	}
-	var value = bucket.write()
-
-	// Insert into node.
-	key = cloneBytes(key)
-	c.node().put(key, key, value, 0, bucketLeafFlag)
-
-	// Since subbuckets are not allowed on inline buckets, we need to
-	// dereference the inline page, if it exists. This will cause the bucket
-	// to be treated as a regular, non-inline bucket for the rest of the tx.
-	b.page = nil
-
-	return b.Bucket(key), nil
-}
-
-// CreateBucketIfNotExists creates a new bucket if it doesn't already exist and returns a reference to it.
-// Returns an error if the bucket name is blank, or if the bucket name is too long.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (b *Bucket) CreateBucketIfNotExists(key []byte) (*Bucket, error) {
-	child, err := b.CreateBucket(key)
-	if err == ErrBucketExists {
-		return b.Bucket(key), nil
-	} else if err != nil {
-		return nil, err
-	}
-	return child, nil
-}
-
-// DeleteBucket deletes a bucket at the given key.
-// Returns an error if the bucket does not exists, or if the key represents a non-bucket value.
-func (b *Bucket) DeleteBucket(key []byte) error {
-	if b.tx.db == nil {
-		return ErrTxClosed
-	} else if !b.Writable() {
-		return ErrTxNotWritable
-	}
-
-	// Move cursor to correct position.
-	c := b.Cursor()
-	k, _, flags := c.seek(key)
-
-	// Return an error if bucket doesn't exist or is not a bucket.
-	if !bytes.Equal(key, k) {
-		return ErrBucketNotFound
-	} else if (flags & bucketLeafFlag) == 0 {
-		return ErrIncompatibleValue
-	}
-
-	// Recursively delete all child buckets.
-	child := b.Bucket(key)
-	err := child.ForEach(func(k, v []byte) error {
-		if v == nil {
-			if err := child.DeleteBucket(k); err != nil {
-				return fmt.Errorf("delete bucket: %s", err)
-			}
-		}
-		return nil
-	})
-	if err != nil {
-		return err
-	}
-
-	// Remove cached copy.
-	delete(b.buckets, string(key))
-
-	// Release all bucket pages to freelist.
-	child.nodes = nil
-	child.rootNode = nil
-	child.free()
-
-	// Delete the node if we have a matching key.
-	c.node().del(key)
-
-	return nil
-}
-
-// Get retrieves the value for a key in the bucket.
-// Returns a nil value if the key does not exist or if the key is a nested bucket.
-// The returned value is only valid for the life of the transaction.
-func (b *Bucket) Get(key []byte) []byte {
-	k, v, flags := b.Cursor().seek(key)
-
-	// Return nil if this is a bucket.
-	if (flags & bucketLeafFlag) != 0 {
-		return nil
-	}
-
-	// If our target node isn't the same key as what's passed in then return nil.
-	if !bytes.Equal(key, k) {
-		return nil
-	}
-	return v
-}
-
-// Put sets the value for a key in the bucket.
-// If the key exist then its previous value will be overwritten.
-// Supplied value must remain valid for the life of the transaction.
-// Returns an error if the bucket was created from a read-only transaction, if the key is blank, if the key is too large, or if the value is too large.
-func (b *Bucket) Put(key []byte, value []byte) error {
-	if b.tx.db == nil {
-		return ErrTxClosed
-	} else if !b.Writable() {
-		return ErrTxNotWritable
-	} else if len(key) == 0 {
-		return ErrKeyRequired
-	} else if len(key) > MaxKeySize {
-		return ErrKeyTooLarge
-	} else if int64(len(value)) > MaxValueSize {
-		return ErrValueTooLarge
-	}
-
-	// Move cursor to correct position.
-	c := b.Cursor()
-	k, _, flags := c.seek(key)
-
-	// Return an error if there is an existing key with a bucket value.
-	if bytes.Equal(key, k) && (flags&bucketLeafFlag) != 0 {
-		return ErrIncompatibleValue
-	}
-
-	// Insert into node.
-	key = cloneBytes(key)
-	c.node().put(key, key, value, 0, 0)
-
-	return nil
-}
-
-// Delete removes a key from the bucket.
-// If the key does not exist then nothing is done and a nil error is returned.
-// Returns an error if the bucket was created from a read-only transaction.
-func (b *Bucket) Delete(key []byte) error {
-	if b.tx.db == nil {
-		return ErrTxClosed
-	} else if !b.Writable() {
-		return ErrTxNotWritable
-	}
-
-	// Move cursor to correct position.
-	c := b.Cursor()
-	k, _, flags := c.seek(key)
-
-	// Return nil if the key doesn't exist.
-	if !bytes.Equal(key, k) {
-		return nil
-	}
-
-	// Return an error if there is already existing bucket value.
-	if (flags & bucketLeafFlag) != 0 {
-		return ErrIncompatibleValue
-	}
-
-	// Delete the node if we have a matching key.
-	c.node().del(key)
-
-	return nil
-}
-
-// Sequence returns the current integer for the bucket without incrementing it.
-func (b *Bucket) Sequence() uint64 { return b.bucket.sequence }
-
-// SetSequence updates the sequence number for the bucket.
-func (b *Bucket) SetSequence(v uint64) error {
-	if b.tx.db == nil {
-		return ErrTxClosed
-	} else if !b.Writable() {
-		return ErrTxNotWritable
-	}
-
-	// Materialize the root node if it hasn't been already so that the
-	// bucket will be saved during commit.
-	if b.rootNode == nil {
-		_ = b.node(b.root, nil)
-	}
-
-	// Increment and return the sequence.
-	b.bucket.sequence = v
-	return nil
-}
-
-// NextSequence returns an autoincrementing integer for the bucket.
-func (b *Bucket) NextSequence() (uint64, error) {
-	if b.tx.db == nil {
-		return 0, ErrTxClosed
-	} else if !b.Writable() {
-		return 0, ErrTxNotWritable
-	}
-
-	// Materialize the root node if it hasn't been already so that the
-	// bucket will be saved during commit.
-	if b.rootNode == nil {
-		_ = b.node(b.root, nil)
-	}
-
-	// Increment and return the sequence.
-	b.bucket.sequence++
-	return b.bucket.sequence, nil
-}
-
-// ForEach executes a function for each key/value pair in a bucket.
-// If the provided function returns an error then the iteration is stopped and
-// the error is returned to the caller. The provided function must not modify
-// the bucket; this will result in undefined behavior.
-func (b *Bucket) ForEach(fn func(k, v []byte) error) error {
-	if b.tx.db == nil {
-		return ErrTxClosed
-	}
-	c := b.Cursor()
-	for k, v := c.First(); k != nil; k, v = c.Next() {
-		if err := fn(k, v); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// Stat returns stats on a bucket.
-func (b *Bucket) Stats() BucketStats {
-	var s, subStats BucketStats
-	pageSize := b.tx.db.pageSize
-	s.BucketN += 1
-	if b.root == 0 {
-		s.InlineBucketN += 1
-	}
-	b.forEachPage(func(p *page, depth int) {
-		if (p.flags & leafPageFlag) != 0 {
-			s.KeyN += int(p.count)
-
-			// used totals the used bytes for the page
-			used := pageHeaderSize
-
-			if p.count != 0 {
-				// If page has any elements, add all element headers.
-				used += leafPageElementSize * int(p.count-1)
-
-				// Add all element key, value sizes.
-				// The computation takes advantage of the fact that the position
-				// of the last element's key/value equals to the total of the sizes
-				// of all previous elements' keys and values.
-				// It also includes the last element's header.
-				lastElement := p.leafPageElement(p.count - 1)
-				used += int(lastElement.pos + lastElement.ksize + lastElement.vsize)
-			}
-
-			if b.root == 0 {
-				// For inlined bucket just update the inline stats
-				s.InlineBucketInuse += used
-			} else {
-				// For non-inlined bucket update all the leaf stats
-				s.LeafPageN++
-				s.LeafInuse += used
-				s.LeafOverflowN += int(p.overflow)
-
-				// Collect stats from sub-buckets.
-				// Do that by iterating over all element headers
-				// looking for the ones with the bucketLeafFlag.
-				for i := uint16(0); i < p.count; i++ {
-					e := p.leafPageElement(i)
-					if (e.flags & bucketLeafFlag) != 0 {
-						// For any bucket element, open the element value
-						// and recursively call Stats on the contained bucket.
-						subStats.Add(b.openBucket(e.value()).Stats())
-					}
-				}
-			}
-		} else if (p.flags & branchPageFlag) != 0 {
-			s.BranchPageN++
-			lastElement := p.branchPageElement(p.count - 1)
-
-			// used totals the used bytes for the page
-			// Add header and all element headers.
-			used := pageHeaderSize + (branchPageElementSize * int(p.count-1))
-
-			// Add size of all keys and values.
-			// Again, use the fact that last element's position equals to
-			// the total of key, value sizes of all previous elements.
-			used += int(lastElement.pos + lastElement.ksize)
-			s.BranchInuse += used
-			s.BranchOverflowN += int(p.overflow)
-		}
-
-		// Keep track of maximum page depth.
-		if depth+1 > s.Depth {
-			s.Depth = (depth + 1)
-		}
-	})
-
-	// Alloc stats can be computed from page counts and pageSize.
-	s.BranchAlloc = (s.BranchPageN + s.BranchOverflowN) * pageSize
-	s.LeafAlloc = (s.LeafPageN + s.LeafOverflowN) * pageSize
-
-	// Add the max depth of sub-buckets to get total nested depth.
-	s.Depth += subStats.Depth
-	// Add the stats for all sub-buckets
-	s.Add(subStats)
-	return s
-}
-
-// forEachPage iterates over every page in a bucket, including inline pages.
-func (b *Bucket) forEachPage(fn func(*page, int)) {
-	// If we have an inline page then just use that.
-	if b.page != nil {
-		fn(b.page, 0)
-		return
-	}
-
-	// Otherwise traverse the page hierarchy.
-	b.tx.forEachPage(b.root, 0, fn)
-}
-
-// forEachPageNode iterates over every page (or node) in a bucket.
-// This also includes inline pages.
-func (b *Bucket) forEachPageNode(fn func(*page, *node, int)) {
-	// If we have an inline page or root node then just use that.
-	if b.page != nil {
-		fn(b.page, nil, 0)
-		return
-	}
-	b._forEachPageNode(b.root, 0, fn)
-}
-
-func (b *Bucket) _forEachPageNode(pgid pgid, depth int, fn func(*page, *node, int)) {
-	var p, n = b.pageNode(pgid)
-
-	// Execute function.
-	fn(p, n, depth)
-
-	// Recursively loop over children.
-	if p != nil {
-		if (p.flags & branchPageFlag) != 0 {
-			for i := 0; i < int(p.count); i++ {
-				elem := p.branchPageElement(uint16(i))
-				b._forEachPageNode(elem.pgid, depth+1, fn)
-			}
-		}
-	} else {
-		if !n.isLeaf {
-			for _, inode := range n.inodes {
-				b._forEachPageNode(inode.pgid, depth+1, fn)
-			}
-		}
-	}
-}
-
-// spill writes all the nodes for this bucket to dirty pages.
-func (b *Bucket) spill() error {
-	// Spill all child buckets first.
-	for name, child := range b.buckets {
-		// If the child bucket is small enough and it has no child buckets then
-		// write it inline into the parent bucket's page. Otherwise spill it
-		// like a normal bucket and make the parent value a pointer to the page.
-		var value []byte
-		if child.inlineable() {
-			child.free()
-			value = child.write()
-		} else {
-			if err := child.spill(); err != nil {
-				return err
-			}
-
-			// Update the child bucket header in this bucket.
-			value = make([]byte, unsafe.Sizeof(bucket{}))
-			var bucket = (*bucket)(unsafe.Pointer(&value[0]))
-			*bucket = *child.bucket
-		}
-
-		// Skip writing the bucket if there are no materialized nodes.
-		if child.rootNode == nil {
-			continue
-		}
-
-		// Update parent node.
-		var c = b.Cursor()
-		k, _, flags := c.seek([]byte(name))
-		if !bytes.Equal([]byte(name), k) {
-			panic(fmt.Sprintf("misplaced bucket header: %x -> %x", []byte(name), k))
-		}
-		if flags&bucketLeafFlag == 0 {
-			panic(fmt.Sprintf("unexpected bucket header flag: %x", flags))
-		}
-		c.node().put([]byte(name), []byte(name), value, 0, bucketLeafFlag)
-	}
-
-	// Ignore if there's not a materialized root node.
-	if b.rootNode == nil {
-		return nil
-	}
-
-	// Spill nodes.
-	if err := b.rootNode.spill(); err != nil {
-		return err
-	}
-	b.rootNode = b.rootNode.root()
-
-	// Update the root node for this bucket.
-	if b.rootNode.pgid >= b.tx.meta.pgid {
-		panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", b.rootNode.pgid, b.tx.meta.pgid))
-	}
-	b.root = b.rootNode.pgid
-
-	return nil
-}
-
-// inlineable returns true if a bucket is small enough to be written inline
-// and if it contains no subbuckets. Otherwise returns false.
-func (b *Bucket) inlineable() bool {
-	var n = b.rootNode
-
-	// Bucket must only contain a single leaf node.
-	if n == nil || !n.isLeaf {
-		return false
-	}
-
-	// Bucket is not inlineable if it contains subbuckets or if it goes beyond
-	// our threshold for inline bucket size.
-	var size = pageHeaderSize
-	for _, inode := range n.inodes {
-		size += leafPageElementSize + len(inode.key) + len(inode.value)
-
-		if inode.flags&bucketLeafFlag != 0 {
-			return false
-		} else if size > b.maxInlineBucketSize() {
-			return false
-		}
-	}
-
-	return true
-}
-
-// Returns the maximum total size of a bucket to make it a candidate for inlining.
-func (b *Bucket) maxInlineBucketSize() int {
-	return b.tx.db.pageSize / 4
-}
-
-// write allocates and writes a bucket to a byte slice.
-func (b *Bucket) write() []byte {
-	// Allocate the appropriate size.
-	var n = b.rootNode
-	var value = make([]byte, bucketHeaderSize+n.size())
-
-	// Write a bucket header.
-	var bucket = (*bucket)(unsafe.Pointer(&value[0]))
-	*bucket = *b.bucket
-
-	// Convert byte slice to a fake page and write the root node.
-	var p = (*page)(unsafe.Pointer(&value[bucketHeaderSize]))
-	n.write(p)
-
-	return value
-}
-
-// rebalance attempts to balance all nodes.
-func (b *Bucket) rebalance() {
-	for _, n := range b.nodes {
-		n.rebalance()
-	}
-	for _, child := range b.buckets {
-		child.rebalance()
-	}
-}
-
-// node creates a node from a page and associates it with a given parent.
-func (b *Bucket) node(pgid pgid, parent *node) *node {
-	_assert(b.nodes != nil, "nodes map expected")
-
-	// Retrieve node if it's already been created.
-	if n := b.nodes[pgid]; n != nil {
-		return n
-	}
-
-	// Otherwise create a node and cache it.
-	n := &node{bucket: b, parent: parent}
-	if parent == nil {
-		b.rootNode = n
-	} else {
-		parent.children = append(parent.children, n)
-	}
-
-	// Use the inline page if this is an inline bucket.
-	var p = b.page
-	if p == nil {
-		p = b.tx.page(pgid)
-	}
-
-	// Read the page into the node and cache it.
-	n.read(p)
-	b.nodes[pgid] = n
-
-	// Update statistics.
-	b.tx.stats.NodeCount++
-
-	return n
-}
-
-// free recursively frees all pages in the bucket.
-func (b *Bucket) free() {
-	if b.root == 0 {
-		return
-	}
-
-	var tx = b.tx
-	b.forEachPageNode(func(p *page, n *node, _ int) {
-		if p != nil {
-			tx.db.freelist.free(tx.meta.txid, p)
-		} else {
-			n.free()
-		}
-	})
-	b.root = 0
-}
-
-// dereference removes all references to the old mmap.
-func (b *Bucket) dereference() {
-	if b.rootNode != nil {
-		b.rootNode.root().dereference()
-	}
-
-	for _, child := range b.buckets {
-		child.dereference()
-	}
-}
-
-// pageNode returns the in-memory node, if it exists.
-// Otherwise returns the underlying page.
-func (b *Bucket) pageNode(id pgid) (*page, *node) {
-	// Inline buckets have a fake page embedded in their value so treat them
-	// differently. We'll return the rootNode (if available) or the fake page.
-	if b.root == 0 {
-		if id != 0 {
-			panic(fmt.Sprintf("inline bucket non-zero page access(2): %d != 0", id))
-		}
-		if b.rootNode != nil {
-			return nil, b.rootNode
-		}
-		return b.page, nil
-	}
-
-	// Check the node cache for non-inline buckets.
-	if b.nodes != nil {
-		if n := b.nodes[id]; n != nil {
-			return nil, n
-		}
-	}
-
-	// Finally lookup the page from the transaction if no node is materialized.
-	return b.tx.page(id), nil
-}
-
-// BucketStats records statistics about resources used by a bucket.
-type BucketStats struct {
-	// Page count statistics.
-	BranchPageN     int // number of logical branch pages
-	BranchOverflowN int // number of physical branch overflow pages
-	LeafPageN       int // number of logical leaf pages
-	LeafOverflowN   int // number of physical leaf overflow pages
-
-	// Tree statistics.
-	KeyN  int // number of keys/value pairs
-	Depth int // number of levels in B+tree
-
-	// Page size utilization.
-	BranchAlloc int // bytes allocated for physical branch pages
-	BranchInuse int // bytes actually used for branch data
-	LeafAlloc   int // bytes allocated for physical leaf pages
-	LeafInuse   int // bytes actually used for leaf data
-
-	// Bucket statistics
-	BucketN           int // total number of buckets including the top bucket
-	InlineBucketN     int // total number on inlined buckets
-	InlineBucketInuse int // bytes used for inlined buckets (also accounted for in LeafInuse)
-}
-
-func (s *BucketStats) Add(other BucketStats) {
-	s.BranchPageN += other.BranchPageN
-	s.BranchOverflowN += other.BranchOverflowN
-	s.LeafPageN += other.LeafPageN
-	s.LeafOverflowN += other.LeafOverflowN
-	s.KeyN += other.KeyN
-	if s.Depth < other.Depth {
-		s.Depth = other.Depth
-	}
-	s.BranchAlloc += other.BranchAlloc
-	s.BranchInuse += other.BranchInuse
-	s.LeafAlloc += other.LeafAlloc
-	s.LeafInuse += other.LeafInuse
-
-	s.BucketN += other.BucketN
-	s.InlineBucketN += other.InlineBucketN
-	s.InlineBucketInuse += other.InlineBucketInuse
-}
-
-// cloneBytes returns a copy of a given slice.
-func cloneBytes(v []byte) []byte {
-	var clone = make([]byte, len(v))
-	copy(clone, v)
-	return clone
-}
diff --git a/vendor/github.com/etcd-io/bbolt/cursor.go b/vendor/github.com/etcd-io/bbolt/cursor.go
deleted file mode 100644
index 3000aced6c..0000000000
--- a/vendor/github.com/etcd-io/bbolt/cursor.go
+++ /dev/null
@@ -1,396 +0,0 @@
-package bbolt
-
-import (
-	"bytes"
-	"fmt"
-	"sort"
-)
-
-// Cursor represents an iterator that can traverse over all key/value pairs in a bucket in sorted order.
-// Cursors see nested buckets with value == nil.
-// Cursors can be obtained from a transaction and are valid as long as the transaction is open.
-//
-// Keys and values returned from the cursor are only valid for the life of the transaction.
-//
-// Changing data while traversing with a cursor may cause it to be invalidated
-// and return unexpected keys and/or values. You must reposition your cursor
-// after mutating data.
-type Cursor struct {
-	bucket *Bucket
-	stack  []elemRef
-}
-
-// Bucket returns the bucket that this cursor was created from.
-func (c *Cursor) Bucket() *Bucket {
-	return c.bucket
-}
-
-// First moves the cursor to the first item in the bucket and returns its key and value.
-// If the bucket is empty then a nil key and value are returned.
-// The returned key and value are only valid for the life of the transaction.
-func (c *Cursor) First() (key []byte, value []byte) {
-	_assert(c.bucket.tx.db != nil, "tx closed")
-	c.stack = c.stack[:0]
-	p, n := c.bucket.pageNode(c.bucket.root)
-	c.stack = append(c.stack, elemRef{page: p, node: n, index: 0})
-	c.first()
-
-	// If we land on an empty page then move to the next value.
-	// https://github.com/boltdb/bolt/issues/450
-	if c.stack[len(c.stack)-1].count() == 0 {
-		c.next()
-	}
-
-	k, v, flags := c.keyValue()
-	if (flags & uint32(bucketLeafFlag)) != 0 {
-		return k, nil
-	}
-	return k, v
-
-}
-
-// Last moves the cursor to the last item in the bucket and returns its key and value.
-// If the bucket is empty then a nil key and value are returned.
-// The returned key and value are only valid for the life of the transaction.
-func (c *Cursor) Last() (key []byte, value []byte) {
-	_assert(c.bucket.tx.db != nil, "tx closed")
-	c.stack = c.stack[:0]
-	p, n := c.bucket.pageNode(c.bucket.root)
-	ref := elemRef{page: p, node: n}
-	ref.index = ref.count() - 1
-	c.stack = append(c.stack, ref)
-	c.last()
-	k, v, flags := c.keyValue()
-	if (flags & uint32(bucketLeafFlag)) != 0 {
-		return k, nil
-	}
-	return k, v
-}
-
-// Next moves the cursor to the next item in the bucket and returns its key and value.
-// If the cursor is at the end of the bucket then a nil key and value are returned.
-// The returned key and value are only valid for the life of the transaction.
-func (c *Cursor) Next() (key []byte, value []byte) {
-	_assert(c.bucket.tx.db != nil, "tx closed")
-	k, v, flags := c.next()
-	if (flags & uint32(bucketLeafFlag)) != 0 {
-		return k, nil
-	}
-	return k, v
-}
-
-// Prev moves the cursor to the previous item in the bucket and returns its key and value.
-// If the cursor is at the beginning of the bucket then a nil key and value are returned.
-// The returned key and value are only valid for the life of the transaction.
-func (c *Cursor) Prev() (key []byte, value []byte) {
-	_assert(c.bucket.tx.db != nil, "tx closed")
-
-	// Attempt to move back one element until we're successful.
-	// Move up the stack as we hit the beginning of each page in our stack.
-	for i := len(c.stack) - 1; i >= 0; i-- {
-		elem := &c.stack[i]
-		if elem.index > 0 {
-			elem.index--
-			break
-		}
-		c.stack = c.stack[:i]
-	}
-
-	// If we've hit the end then return nil.
-	if len(c.stack) == 0 {
-		return nil, nil
-	}
-
-	// Move down the stack to find the last element of the last leaf under this branch.
-	c.last()
-	k, v, flags := c.keyValue()
-	if (flags & uint32(bucketLeafFlag)) != 0 {
-		return k, nil
-	}
-	return k, v
-}
-
-// Seek moves the cursor to a given key and returns it.
-// If the key does not exist then the next key is used. If no keys
-// follow, a nil key is returned.
-// The returned key and value are only valid for the life of the transaction.
-func (c *Cursor) Seek(seek []byte) (key []byte, value []byte) {
-	k, v, flags := c.seek(seek)
-
-	// If we ended up after the last element of a page then move to the next one.
-	if ref := &c.stack[len(c.stack)-1]; ref.index >= ref.count() {
-		k, v, flags = c.next()
-	}
-
-	if k == nil {
-		return nil, nil
-	} else if (flags & uint32(bucketLeafFlag)) != 0 {
-		return k, nil
-	}
-	return k, v
-}
-
-// Delete removes the current key/value under the cursor from the bucket.
-// Delete fails if current key/value is a bucket or if the transaction is not writable.
-func (c *Cursor) Delete() error {
-	if c.bucket.tx.db == nil {
-		return ErrTxClosed
-	} else if !c.bucket.Writable() {
-		return ErrTxNotWritable
-	}
-
-	key, _, flags := c.keyValue()
-	// Return an error if current value is a bucket.
-	if (flags & bucketLeafFlag) != 0 {
-		return ErrIncompatibleValue
-	}
-	c.node().del(key)
-
-	return nil
-}
-
-// seek moves the cursor to a given key and returns it.
-// If the key does not exist then the next key is used.
-func (c *Cursor) seek(seek []byte) (key []byte, value []byte, flags uint32) {
-	_assert(c.bucket.tx.db != nil, "tx closed")
-
-	// Start from root page/node and traverse to correct page.
-	c.stack = c.stack[:0]
-	c.search(seek, c.bucket.root)
-
-	// If this is a bucket then return a nil value.
-	return c.keyValue()
-}
-
-// first moves the cursor to the first leaf element under the last page in the stack.
-func (c *Cursor) first() {
-	for {
-		// Exit when we hit a leaf page.
-		var ref = &c.stack[len(c.stack)-1]
-		if ref.isLeaf() {
-			break
-		}
-
-		// Keep adding pages pointing to the first element to the stack.
-		var pgid pgid
-		if ref.node != nil {
-			pgid = ref.node.inodes[ref.index].pgid
-		} else {
-			pgid = ref.page.branchPageElement(uint16(ref.index)).pgid
-		}
-		p, n := c.bucket.pageNode(pgid)
-		c.stack = append(c.stack, elemRef{page: p, node: n, index: 0})
-	}
-}
-
-// last moves the cursor to the last leaf element under the last page in the stack.
-func (c *Cursor) last() {
-	for {
-		// Exit when we hit a leaf page.
-		ref := &c.stack[len(c.stack)-1]
-		if ref.isLeaf() {
-			break
-		}
-
-		// Keep adding pages pointing to the last element in the stack.
-		var pgid pgid
-		if ref.node != nil {
-			pgid = ref.node.inodes[ref.index].pgid
-		} else {
-			pgid = ref.page.branchPageElement(uint16(ref.index)).pgid
-		}
-		p, n := c.bucket.pageNode(pgid)
-
-		var nextRef = elemRef{page: p, node: n}
-		nextRef.index = nextRef.count() - 1
-		c.stack = append(c.stack, nextRef)
-	}
-}
-
-// next moves to the next leaf element and returns the key and value.
-// If the cursor is at the last leaf element then it stays there and returns nil.
-func (c *Cursor) next() (key []byte, value []byte, flags uint32) {
-	for {
-		// Attempt to move over one element until we're successful.
-		// Move up the stack as we hit the end of each page in our stack.
-		var i int
-		for i = len(c.stack) - 1; i >= 0; i-- {
-			elem := &c.stack[i]
-			if elem.index < elem.count()-1 {
-				elem.index++
-				break
-			}
-		}
-
-		// If we've hit the root page then stop and return. This will leave the
-		// cursor on the last element of the last page.
-		if i == -1 {
-			return nil, nil, 0
-		}
-
-		// Otherwise start from where we left off in the stack and find the
-		// first element of the first leaf page.
-		c.stack = c.stack[:i+1]
-		c.first()
-
-		// If this is an empty page then restart and move back up the stack.
-		// https://github.com/boltdb/bolt/issues/450
-		if c.stack[len(c.stack)-1].count() == 0 {
-			continue
-		}
-
-		return c.keyValue()
-	}
-}
-
-// search recursively performs a binary search against a given page/node until it finds a given key.
-func (c *Cursor) search(key []byte, pgid pgid) {
-	p, n := c.bucket.pageNode(pgid)
-	if p != nil && (p.flags&(branchPageFlag|leafPageFlag)) == 0 {
-		panic(fmt.Sprintf("invalid page type: %d: %x", p.id, p.flags))
-	}
-	e := elemRef{page: p, node: n}
-	c.stack = append(c.stack, e)
-
-	// If we're on a leaf page/node then find the specific node.
-	if e.isLeaf() {
-		c.nsearch(key)
-		return
-	}
-
-	if n != nil {
-		c.searchNode(key, n)
-		return
-	}
-	c.searchPage(key, p)
-}
-
-func (c *Cursor) searchNode(key []byte, n *node) {
-	var exact bool
-	index := sort.Search(len(n.inodes), func(i int) bool {
-		// TODO(benbjohnson): Optimize this range search. It's a bit hacky right now.
-		// sort.Search() finds the lowest index where f() != -1 but we need the highest index.
-		ret := bytes.Compare(n.inodes[i].key, key)
-		if ret == 0 {
-			exact = true
-		}
-		return ret != -1
-	})
-	if !exact && index > 0 {
-		index--
-	}
-	c.stack[len(c.stack)-1].index = index
-
-	// Recursively search to the next page.
-	c.search(key, n.inodes[index].pgid)
-}
-
-func (c *Cursor) searchPage(key []byte, p *page) {
-	// Binary search for the correct range.
-	inodes := p.branchPageElements()
-
-	var exact bool
-	index := sort.Search(int(p.count), func(i int) bool {
-		// TODO(benbjohnson): Optimize this range search. It's a bit hacky right now.
-		// sort.Search() finds the lowest index where f() != -1 but we need the highest index.
-		ret := bytes.Compare(inodes[i].key(), key)
-		if ret == 0 {
-			exact = true
-		}
-		return ret != -1
-	})
-	if !exact && index > 0 {
-		index--
-	}
-	c.stack[len(c.stack)-1].index = index
-
-	// Recursively search to the next page.
-	c.search(key, inodes[index].pgid)
-}
-
-// nsearch searches the leaf node on the top of the stack for a key.
-func (c *Cursor) nsearch(key []byte) {
-	e := &c.stack[len(c.stack)-1]
-	p, n := e.page, e.node
-
-	// If we have a node then search its inodes.
-	if n != nil {
-		index := sort.Search(len(n.inodes), func(i int) bool {
-			return bytes.Compare(n.inodes[i].key, key) != -1
-		})
-		e.index = index
-		return
-	}
-
-	// If we have a page then search its leaf elements.
-	inodes := p.leafPageElements()
-	index := sort.Search(int(p.count), func(i int) bool {
-		return bytes.Compare(inodes[i].key(), key) != -1
-	})
-	e.index = index
-}
-
-// keyValue returns the key and value of the current leaf element.
-func (c *Cursor) keyValue() ([]byte, []byte, uint32) {
-	ref := &c.stack[len(c.stack)-1]
-
-	// If the cursor is pointing to the end of page/node then return nil.
-	if ref.count() == 0 || ref.index >= ref.count() {
-		return nil, nil, 0
-	}
-
-	// Retrieve value from node.
-	if ref.node != nil {
-		inode := &ref.node.inodes[ref.index]
-		return inode.key, inode.value, inode.flags
-	}
-
-	// Or retrieve value from page.
-	elem := ref.page.leafPageElement(uint16(ref.index))
-	return elem.key(), elem.value(), elem.flags
-}
-
-// node returns the node that the cursor is currently positioned on.
-func (c *Cursor) node() *node {
-	_assert(len(c.stack) > 0, "accessing a node with a zero-length cursor stack")
-
-	// If the top of the stack is a leaf node then just return it.
-	if ref := &c.stack[len(c.stack)-1]; ref.node != nil && ref.isLeaf() {
-		return ref.node
-	}
-
-	// Start from root and traverse down the hierarchy.
-	var n = c.stack[0].node
-	if n == nil {
-		n = c.bucket.node(c.stack[0].page.id, nil)
-	}
-	for _, ref := range c.stack[:len(c.stack)-1] {
-		_assert(!n.isLeaf, "expected branch node")
-		n = n.childAt(int(ref.index))
-	}
-	_assert(n.isLeaf, "expected leaf node")
-	return n
-}
-
-// elemRef represents a reference to an element on a given page/node.
-type elemRef struct {
-	page  *page
-	node  *node
-	index int
-}
-
-// isLeaf returns whether the ref is pointing at a leaf page/node.
-func (r *elemRef) isLeaf() bool {
-	if r.node != nil {
-		return r.node.isLeaf
-	}
-	return (r.page.flags & leafPageFlag) != 0
-}
-
-// count returns the number of inodes or page elements.
-func (r *elemRef) count() int {
-	if r.node != nil {
-		return len(r.node.inodes)
-	}
-	return int(r.page.count)
-}
diff --git a/vendor/github.com/etcd-io/bbolt/db.go b/vendor/github.com/etcd-io/bbolt/db.go
deleted file mode 100644
index 870c8b1cc9..0000000000
--- a/vendor/github.com/etcd-io/bbolt/db.go
+++ /dev/null
@@ -1,1174 +0,0 @@
-package bbolt
-
-import (
-	"errors"
-	"fmt"
-	"hash/fnv"
-	"log"
-	"os"
-	"runtime"
-	"sort"
-	"sync"
-	"time"
-	"unsafe"
-)
-
-// The largest step that can be taken when remapping the mmap.
-const maxMmapStep = 1 << 30 // 1GB
-
-// The data file format version.
-const version = 2
-
-// Represents a marker value to indicate that a file is a Bolt DB.
-const magic uint32 = 0xED0CDAED
-
-const pgidNoFreelist pgid = 0xffffffffffffffff
-
-// IgnoreNoSync specifies whether the NoSync field of a DB is ignored when
-// syncing changes to a file.  This is required as some operating systems,
-// such as OpenBSD, do not have a unified buffer cache (UBC) and writes
-// must be synchronized using the msync(2) syscall.
-const IgnoreNoSync = runtime.GOOS == "openbsd"
-
-// Default values if not set in a DB instance.
-const (
-	DefaultMaxBatchSize  int = 1000
-	DefaultMaxBatchDelay     = 10 * time.Millisecond
-	DefaultAllocSize         = 16 * 1024 * 1024
-)
-
-// default page size for db is set to the OS page size.
-var defaultPageSize = os.Getpagesize()
-
-// The time elapsed between consecutive file locking attempts.
-const flockRetryTimeout = 50 * time.Millisecond
-
-// FreelistType is the type of the freelist backend
-type FreelistType string
-
-const (
-	// FreelistArrayType indicates backend freelist type is array
-	FreelistArrayType = FreelistType("array")
-	// FreelistMapType indicates backend freelist type is hashmap
-	FreelistMapType = FreelistType("hashmap")
-)
-
-// DB represents a collection of buckets persisted to a file on disk.
-// All data access is performed through transactions which can be obtained through the DB.
-// All the functions on DB will return a ErrDatabaseNotOpen if accessed before Open() is called.
-type DB struct {
-	// When enabled, the database will perform a Check() after every commit.
-	// A panic is issued if the database is in an inconsistent state. This
-	// flag has a large performance impact so it should only be used for
-	// debugging purposes.
-	StrictMode bool
-
-	// Setting the NoSync flag will cause the database to skip fsync()
-	// calls after each commit. This can be useful when bulk loading data
-	// into a database and you can restart the bulk load in the event of
-	// a system failure or database corruption. Do not set this flag for
-	// normal use.
-	//
-	// If the package global IgnoreNoSync constant is true, this value is
-	// ignored.  See the comment on that constant for more details.
-	//
-	// THIS IS UNSAFE. PLEASE USE WITH CAUTION.
-	NoSync bool
-
-	// When true, skips syncing freelist to disk. This improves the database
-	// write performance under normal operation, but requires a full database
-	// re-sync during recovery.
-	NoFreelistSync bool
-
-	// FreelistType sets the backend freelist type. There are two options. Array which is simple but endures
-	// dramatic performance degradation if database is large and framentation in freelist is common.
-	// The alternative one is using hashmap, it is faster in almost all circumstances
-	// but it doesn't guarantee that it offers the smallest page id available. In normal case it is safe.
-	// The default type is array
-	FreelistType FreelistType
-
-	// When true, skips the truncate call when growing the database.
-	// Setting this to true is only safe on non-ext3/ext4 systems.
-	// Skipping truncation avoids preallocation of hard drive space and
-	// bypasses a truncate() and fsync() syscall on remapping.
-	//
-	// https://github.com/boltdb/bolt/issues/284
-	NoGrowSync bool
-
-	// If you want to read the entire database fast, you can set MmapFlag to
-	// syscall.MAP_POPULATE on Linux 2.6.23+ for sequential read-ahead.
-	MmapFlags int
-
-	// MaxBatchSize is the maximum size of a batch. Default value is
-	// copied from DefaultMaxBatchSize in Open.
-	//
-	// If <=0, disables batching.
-	//
-	// Do not change concurrently with calls to Batch.
-	MaxBatchSize int
-
-	// MaxBatchDelay is the maximum delay before a batch starts.
-	// Default value is copied from DefaultMaxBatchDelay in Open.
-	//
-	// If <=0, effectively disables batching.
-	//
-	// Do not change concurrently with calls to Batch.
-	MaxBatchDelay time.Duration
-
-	// AllocSize is the amount of space allocated when the database
-	// needs to create new pages. This is done to amortize the cost
-	// of truncate() and fsync() when growing the data file.
-	AllocSize int
-
-	path     string
-	openFile func(string, int, os.FileMode) (*os.File, error)
-	file     *os.File
-	dataref  []byte // mmap'ed readonly, write throws SEGV
-	data     *[maxMapSize]byte
-	datasz   int
-	filesz   int // current on disk file size
-	meta0    *meta
-	meta1    *meta
-	pageSize int
-	opened   bool
-	rwtx     *Tx
-	txs      []*Tx
-	stats    Stats
-
-	freelist     *freelist
-	freelistLoad sync.Once
-
-	pagePool sync.Pool
-
-	batchMu sync.Mutex
-	batch   *batch
-
-	rwlock   sync.Mutex   // Allows only one writer at a time.
-	metalock sync.Mutex   // Protects meta page access.
-	mmaplock sync.RWMutex // Protects mmap access during remapping.
-	statlock sync.RWMutex // Protects stats access.
-
-	ops struct {
-		writeAt func(b []byte, off int64) (n int, err error)
-	}
-
-	// Read only mode.
-	// When true, Update() and Begin(true) return ErrDatabaseReadOnly immediately.
-	readOnly bool
-}
-
-// Path returns the path to currently open database file.
-func (db *DB) Path() string {
-	return db.path
-}
-
-// GoString returns the Go string representation of the database.
-func (db *DB) GoString() string {
-	return fmt.Sprintf("bolt.DB{path:%q}", db.path)
-}
-
-// String returns the string representation of the database.
-func (db *DB) String() string {
-	return fmt.Sprintf("DB<%q>", db.path)
-}
-
-// Open creates and opens a database at the given path.
-// If the file does not exist then it will be created automatically.
-// Passing in nil options will cause Bolt to open the database with the default options.
-func Open(path string, mode os.FileMode, options *Options) (*DB, error) {
-	db := &DB{
-		opened: true,
-	}
-	// Set default options if no options are provided.
-	if options == nil {
-		options = DefaultOptions
-	}
-	db.NoSync = options.NoSync
-	db.NoGrowSync = options.NoGrowSync
-	db.MmapFlags = options.MmapFlags
-	db.NoFreelistSync = options.NoFreelistSync
-	db.FreelistType = options.FreelistType
-
-	// Set default values for later DB operations.
-	db.MaxBatchSize = DefaultMaxBatchSize
-	db.MaxBatchDelay = DefaultMaxBatchDelay
-	db.AllocSize = DefaultAllocSize
-
-	flag := os.O_RDWR
-	if options.ReadOnly {
-		flag = os.O_RDONLY
-		db.readOnly = true
-	}
-
-	db.openFile = options.OpenFile
-	if db.openFile == nil {
-		db.openFile = os.OpenFile
-	}
-
-	// Open data file and separate sync handler for metadata writes.
-	db.path = path
-	var err error
-	if db.file, err = db.openFile(db.path, flag|os.O_CREATE, mode); err != nil {
-		_ = db.close()
-		return nil, err
-	}
-
-	// Lock file so that other processes using Bolt in read-write mode cannot
-	// use the database  at the same time. This would cause corruption since
-	// the two processes would write meta pages and free pages separately.
-	// The database file is locked exclusively (only one process can grab the lock)
-	// if !options.ReadOnly.
-	// The database file is locked using the shared lock (more than one process may
-	// hold a lock at the same time) otherwise (options.ReadOnly is set).
-	if err := flock(db, !db.readOnly, options.Timeout); err != nil {
-		_ = db.close()
-		return nil, err
-	}
-
-	// Default values for test hooks
-	db.ops.writeAt = db.file.WriteAt
-
-	if db.pageSize = options.PageSize; db.pageSize == 0 {
-		// Set the default page size to the OS page size.
-		db.pageSize = defaultPageSize
-	}
-
-	// Initialize the database if it doesn't exist.
-	if info, err := db.file.Stat(); err != nil {
-		_ = db.close()
-		return nil, err
-	} else if info.Size() == 0 {
-		// Initialize new files with meta pages.
-		if err := db.init(); err != nil {
-			// clean up file descriptor on initialization fail
-			_ = db.close()
-			return nil, err
-		}
-	} else {
-		// Read the first meta page to determine the page size.
-		var buf [0x1000]byte
-		// If we can't read the page size, but can read a page, assume
-		// it's the same as the OS or one given -- since that's how the
-		// page size was chosen in the first place.
-		//
-		// If the first page is invalid and this OS uses a different
-		// page size than what the database was created with then we
-		// are out of luck and cannot access the database.
-		//
-		// TODO: scan for next page
-		if bw, err := db.file.ReadAt(buf[:], 0); err == nil && bw == len(buf) {
-			if m := db.pageInBuffer(buf[:], 0).meta(); m.validate() == nil {
-				db.pageSize = int(m.pageSize)
-			}
-		} else {
-			_ = db.close()
-			return nil, ErrInvalid
-		}
-	}
-
-	// Initialize page pool.
-	db.pagePool = sync.Pool{
-		New: func() interface{} {
-			return make([]byte, db.pageSize)
-		},
-	}
-
-	// Memory map the data file.
-	if err := db.mmap(options.InitialMmapSize); err != nil {
-		_ = db.close()
-		return nil, err
-	}
-
-	if db.readOnly {
-		return db, nil
-	}
-
-	db.loadFreelist()
-
-	// Flush freelist when transitioning from no sync to sync so
-	// NoFreelistSync unaware boltdb can open the db later.
-	if !db.NoFreelistSync && !db.hasSyncedFreelist() {
-		tx, err := db.Begin(true)
-		if tx != nil {
-			err = tx.Commit()
-		}
-		if err != nil {
-			_ = db.close()
-			return nil, err
-		}
-	}
-
-	// Mark the database as opened and return.
-	return db, nil
-}
-
-// loadFreelist reads the freelist if it is synced, or reconstructs it
-// by scanning the DB if it is not synced. It assumes there are no
-// concurrent accesses being made to the freelist.
-func (db *DB) loadFreelist() {
-	db.freelistLoad.Do(func() {
-		db.freelist = newFreelist(db.FreelistType)
-		if !db.hasSyncedFreelist() {
-			// Reconstruct free list by scanning the DB.
-			db.freelist.readIDs(db.freepages())
-		} else {
-			// Read free list from freelist page.
-			db.freelist.read(db.page(db.meta().freelist))
-		}
-		db.stats.FreePageN = db.freelist.free_count()
-	})
-}
-
-func (db *DB) hasSyncedFreelist() bool {
-	return db.meta().freelist != pgidNoFreelist
-}
-
-// mmap opens the underlying memory-mapped file and initializes the meta references.
-// minsz is the minimum size that the new mmap can be.
-func (db *DB) mmap(minsz int) error {
-	db.mmaplock.Lock()
-	defer db.mmaplock.Unlock()
-
-	info, err := db.file.Stat()
-	if err != nil {
-		return fmt.Errorf("mmap stat error: %s", err)
-	} else if int(info.Size()) < db.pageSize*2 {
-		return fmt.Errorf("file size too small")
-	}
-
-	// Ensure the size is at least the minimum size.
-	var size = int(info.Size())
-	if size < minsz {
-		size = minsz
-	}
-	size, err = db.mmapSize(size)
-	if err != nil {
-		return err
-	}
-
-	// Dereference all mmap references before unmapping.
-	if db.rwtx != nil {
-		db.rwtx.root.dereference()
-	}
-
-	// Unmap existing data before continuing.
-	if err := db.munmap(); err != nil {
-		return err
-	}
-
-	// Memory-map the data file as a byte slice.
-	if err := mmap(db, size); err != nil {
-		return err
-	}
-
-	// Save references to the meta pages.
-	db.meta0 = db.page(0).meta()
-	db.meta1 = db.page(1).meta()
-
-	// Validate the meta pages. We only return an error if both meta pages fail
-	// validation, since meta0 failing validation means that it wasn't saved
-	// properly -- but we can recover using meta1. And vice-versa.
-	err0 := db.meta0.validate()
-	err1 := db.meta1.validate()
-	if err0 != nil && err1 != nil {
-		return err0
-	}
-
-	return nil
-}
-
-// munmap unmaps the data file from memory.
-func (db *DB) munmap() error {
-	if err := munmap(db); err != nil {
-		return fmt.Errorf("unmap error: " + err.Error())
-	}
-	return nil
-}
-
-// mmapSize determines the appropriate size for the mmap given the current size
-// of the database. The minimum size is 32KB and doubles until it reaches 1GB.
-// Returns an error if the new mmap size is greater than the max allowed.
-func (db *DB) mmapSize(size int) (int, error) {
-	// Double the size from 32KB until 1GB.
-	for i := uint(15); i <= 30; i++ {
-		if size <= 1<<i {
-			return 1 << i, nil
-		}
-	}
-
-	// Verify the requested size is not above the maximum allowed.
-	if size > maxMapSize {
-		return 0, fmt.Errorf("mmap too large")
-	}
-
-	// If larger than 1GB then grow by 1GB at a time.
-	sz := int64(size)
-	if remainder := sz % int64(maxMmapStep); remainder > 0 {
-		sz += int64(maxMmapStep) - remainder
-	}
-
-	// Ensure that the mmap size is a multiple of the page size.
-	// This should always be true since we're incrementing in MBs.
-	pageSize := int64(db.pageSize)
-	if (sz % pageSize) != 0 {
-		sz = ((sz / pageSize) + 1) * pageSize
-	}
-
-	// If we've exceeded the max size then only grow up to the max size.
-	if sz > maxMapSize {
-		sz = maxMapSize
-	}
-
-	return int(sz), nil
-}
-
-// init creates a new database file and initializes its meta pages.
-func (db *DB) init() error {
-	// Create two meta pages on a buffer.
-	buf := make([]byte, db.pageSize*4)
-	for i := 0; i < 2; i++ {
-		p := db.pageInBuffer(buf[:], pgid(i))
-		p.id = pgid(i)
-		p.flags = metaPageFlag
-
-		// Initialize the meta page.
-		m := p.meta()
-		m.magic = magic
-		m.version = version
-		m.pageSize = uint32(db.pageSize)
-		m.freelist = 2
-		m.root = bucket{root: 3}
-		m.pgid = 4
-		m.txid = txid(i)
-		m.checksum = m.sum64()
-	}
-
-	// Write an empty freelist at page 3.
-	p := db.pageInBuffer(buf[:], pgid(2))
-	p.id = pgid(2)
-	p.flags = freelistPageFlag
-	p.count = 0
-
-	// Write an empty leaf page at page 4.
-	p = db.pageInBuffer(buf[:], pgid(3))
-	p.id = pgid(3)
-	p.flags = leafPageFlag
-	p.count = 0
-
-	// Write the buffer to our data file.
-	if _, err := db.ops.writeAt(buf, 0); err != nil {
-		return err
-	}
-	if err := fdatasync(db); err != nil {
-		return err
-	}
-
-	return nil
-}
-
-// Close releases all database resources.
-// It will block waiting for any open transactions to finish
-// before closing the database and returning.
-func (db *DB) Close() error {
-	db.rwlock.Lock()
-	defer db.rwlock.Unlock()
-
-	db.metalock.Lock()
-	defer db.metalock.Unlock()
-
-	db.mmaplock.Lock()
-	defer db.mmaplock.Unlock()
-
-	return db.close()
-}
-
-func (db *DB) close() error {
-	if !db.opened {
-		return nil
-	}
-
-	db.opened = false
-
-	db.freelist = nil
-
-	// Clear ops.
-	db.ops.writeAt = nil
-
-	// Close the mmap.
-	if err := db.munmap(); err != nil {
-		return err
-	}
-
-	// Close file handles.
-	if db.file != nil {
-		// No need to unlock read-only file.
-		if !db.readOnly {
-			// Unlock the file.
-			if err := funlock(db); err != nil {
-				log.Printf("bolt.Close(): funlock error: %s", err)
-			}
-		}
-
-		// Close the file descriptor.
-		if err := db.file.Close(); err != nil {
-			return fmt.Errorf("db file close: %s", err)
-		}
-		db.file = nil
-	}
-
-	db.path = ""
-	return nil
-}
-
-// Begin starts a new transaction.
-// Multiple read-only transactions can be used concurrently but only one
-// write transaction can be used at a time. Starting multiple write transactions
-// will cause the calls to block and be serialized until the current write
-// transaction finishes.
-//
-// Transactions should not be dependent on one another. Opening a read
-// transaction and a write transaction in the same goroutine can cause the
-// writer to deadlock because the database periodically needs to re-mmap itself
-// as it grows and it cannot do that while a read transaction is open.
-//
-// If a long running read transaction (for example, a snapshot transaction) is
-// needed, you might want to set DB.InitialMmapSize to a large enough value
-// to avoid potential blocking of write transaction.
-//
-// IMPORTANT: You must close read-only transactions after you are finished or
-// else the database will not reclaim old pages.
-func (db *DB) Begin(writable bool) (*Tx, error) {
-	if writable {
-		return db.beginRWTx()
-	}
-	return db.beginTx()
-}
-
-func (db *DB) beginTx() (*Tx, error) {
-	// Lock the meta pages while we initialize the transaction. We obtain
-	// the meta lock before the mmap lock because that's the order that the
-	// write transaction will obtain them.
-	db.metalock.Lock()
-
-	// Obtain a read-only lock on the mmap. When the mmap is remapped it will
-	// obtain a write lock so all transactions must finish before it can be
-	// remapped.
-	db.mmaplock.RLock()
-
-	// Exit if the database is not open yet.
-	if !db.opened {
-		db.mmaplock.RUnlock()
-		db.metalock.Unlock()
-		return nil, ErrDatabaseNotOpen
-	}
-
-	// Create a transaction associated with the database.
-	t := &Tx{}
-	t.init(db)
-
-	// Keep track of transaction until it closes.
-	db.txs = append(db.txs, t)
-	n := len(db.txs)
-
-	// Unlock the meta pages.
-	db.metalock.Unlock()
-
-	// Update the transaction stats.
-	db.statlock.Lock()
-	db.stats.TxN++
-	db.stats.OpenTxN = n
-	db.statlock.Unlock()
-
-	return t, nil
-}
-
-func (db *DB) beginRWTx() (*Tx, error) {
-	// If the database was opened with Options.ReadOnly, return an error.
-	if db.readOnly {
-		return nil, ErrDatabaseReadOnly
-	}
-
-	// Obtain writer lock. This is released by the transaction when it closes.
-	// This enforces only one writer transaction at a time.
-	db.rwlock.Lock()
-
-	// Once we have the writer lock then we can lock the meta pages so that
-	// we can set up the transaction.
-	db.metalock.Lock()
-	defer db.metalock.Unlock()
-
-	// Exit if the database is not open yet.
-	if !db.opened {
-		db.rwlock.Unlock()
-		return nil, ErrDatabaseNotOpen
-	}
-
-	// Create a transaction associated with the database.
-	t := &Tx{writable: true}
-	t.init(db)
-	db.rwtx = t
-	db.freePages()
-	return t, nil
-}
-
-// freePages releases any pages associated with closed read-only transactions.
-func (db *DB) freePages() {
-	// Free all pending pages prior to earliest open transaction.
-	sort.Sort(txsById(db.txs))
-	minid := txid(0xFFFFFFFFFFFFFFFF)
-	if len(db.txs) > 0 {
-		minid = db.txs[0].meta.txid
-	}
-	if minid > 0 {
-		db.freelist.release(minid - 1)
-	}
-	// Release unused txid extents.
-	for _, t := range db.txs {
-		db.freelist.releaseRange(minid, t.meta.txid-1)
-		minid = t.meta.txid + 1
-	}
-	db.freelist.releaseRange(minid, txid(0xFFFFFFFFFFFFFFFF))
-	// Any page both allocated and freed in an extent is safe to release.
-}
-
-type txsById []*Tx
-
-func (t txsById) Len() int           { return len(t) }
-func (t txsById) Swap(i, j int)      { t[i], t[j] = t[j], t[i] }
-func (t txsById) Less(i, j int) bool { return t[i].meta.txid < t[j].meta.txid }
-
-// removeTx removes a transaction from the database.
-func (db *DB) removeTx(tx *Tx) {
-	// Release the read lock on the mmap.
-	db.mmaplock.RUnlock()
-
-	// Use the meta lock to restrict access to the DB object.
-	db.metalock.Lock()
-
-	// Remove the transaction.
-	for i, t := range db.txs {
-		if t == tx {
-			last := len(db.txs) - 1
-			db.txs[i] = db.txs[last]
-			db.txs[last] = nil
-			db.txs = db.txs[:last]
-			break
-		}
-	}
-	n := len(db.txs)
-
-	// Unlock the meta pages.
-	db.metalock.Unlock()
-
-	// Merge statistics.
-	db.statlock.Lock()
-	db.stats.OpenTxN = n
-	db.stats.TxStats.add(&tx.stats)
-	db.statlock.Unlock()
-}
-
-// Update executes a function within the context of a read-write managed transaction.
-// If no error is returned from the function then the transaction is committed.
-// If an error is returned then the entire transaction is rolled back.
-// Any error that is returned from the function or returned from the commit is
-// returned from the Update() method.
-//
-// Attempting to manually commit or rollback within the function will cause a panic.
-func (db *DB) Update(fn func(*Tx) error) error {
-	t, err := db.Begin(true)
-	if err != nil {
-		return err
-	}
-
-	// Make sure the transaction rolls back in the event of a panic.
-	defer func() {
-		if t.db != nil {
-			t.rollback()
-		}
-	}()
-
-	// Mark as a managed tx so that the inner function cannot manually commit.
-	t.managed = true
-
-	// If an error is returned from the function then rollback and return error.
-	err = fn(t)
-	t.managed = false
-	if err != nil {
-		_ = t.Rollback()
-		return err
-	}
-
-	return t.Commit()
-}
-
-// View executes a function within the context of a managed read-only transaction.
-// Any error that is returned from the function is returned from the View() method.
-//
-// Attempting to manually rollback within the function will cause a panic.
-func (db *DB) View(fn func(*Tx) error) error {
-	t, err := db.Begin(false)
-	if err != nil {
-		return err
-	}
-
-	// Make sure the transaction rolls back in the event of a panic.
-	defer func() {
-		if t.db != nil {
-			t.rollback()
-		}
-	}()
-
-	// Mark as a managed tx so that the inner function cannot manually rollback.
-	t.managed = true
-
-	// If an error is returned from the function then pass it through.
-	err = fn(t)
-	t.managed = false
-	if err != nil {
-		_ = t.Rollback()
-		return err
-	}
-
-	return t.Rollback()
-}
-
-// Batch calls fn as part of a batch. It behaves similar to Update,
-// except:
-//
-// 1. concurrent Batch calls can be combined into a single Bolt
-// transaction.
-//
-// 2. the function passed to Batch may be called multiple times,
-// regardless of whether it returns error or not.
-//
-// This means that Batch function side effects must be idempotent and
-// take permanent effect only after a successful return is seen in
-// caller.
-//
-// The maximum batch size and delay can be adjusted with DB.MaxBatchSize
-// and DB.MaxBatchDelay, respectively.
-//
-// Batch is only useful when there are multiple goroutines calling it.
-func (db *DB) Batch(fn func(*Tx) error) error {
-	errCh := make(chan error, 1)
-
-	db.batchMu.Lock()
-	if (db.batch == nil) || (db.batch != nil && len(db.batch.calls) >= db.MaxBatchSize) {
-		// There is no existing batch, or the existing batch is full; start a new one.
-		db.batch = &batch{
-			db: db,
-		}
-		db.batch.timer = time.AfterFunc(db.MaxBatchDelay, db.batch.trigger)
-	}
-	db.batch.calls = append(db.batch.calls, call{fn: fn, err: errCh})
-	if len(db.batch.calls) >= db.MaxBatchSize {
-		// wake up batch, it's ready to run
-		go db.batch.trigger()
-	}
-	db.batchMu.Unlock()
-
-	err := <-errCh
-	if err == trySolo {
-		err = db.Update(fn)
-	}
-	return err
-}
-
-type call struct {
-	fn  func(*Tx) error
-	err chan<- error
-}
-
-type batch struct {
-	db    *DB
-	timer *time.Timer
-	start sync.Once
-	calls []call
-}
-
-// trigger runs the batch if it hasn't already been run.
-func (b *batch) trigger() {
-	b.start.Do(b.run)
-}
-
-// run performs the transactions in the batch and communicates results
-// back to DB.Batch.
-func (b *batch) run() {
-	b.db.batchMu.Lock()
-	b.timer.Stop()
-	// Make sure no new work is added to this batch, but don't break
-	// other batches.
-	if b.db.batch == b {
-		b.db.batch = nil
-	}
-	b.db.batchMu.Unlock()
-
-retry:
-	for len(b.calls) > 0 {
-		var failIdx = -1
-		err := b.db.Update(func(tx *Tx) error {
-			for i, c := range b.calls {
-				if err := safelyCall(c.fn, tx); err != nil {
-					failIdx = i
-					return err
-				}
-			}
-			return nil
-		})
-
-		if failIdx >= 0 {
-			// take the failing transaction out of the batch. it's
-			// safe to shorten b.calls here because db.batch no longer
-			// points to us, and we hold the mutex anyway.
-			c := b.calls[failIdx]
-			b.calls[failIdx], b.calls = b.calls[len(b.calls)-1], b.calls[:len(b.calls)-1]
-			// tell the submitter re-run it solo, continue with the rest of the batch
-			c.err <- trySolo
-			continue retry
-		}
-
-		// pass success, or bolt internal errors, to all callers
-		for _, c := range b.calls {
-			c.err <- err
-		}
-		break retry
-	}
-}
-
-// trySolo is a special sentinel error value used for signaling that a
-// transaction function should be re-run. It should never be seen by
-// callers.
-var trySolo = errors.New("batch function returned an error and should be re-run solo")
-
-type panicked struct {
-	reason interface{}
-}
-
-func (p panicked) Error() string {
-	if err, ok := p.reason.(error); ok {
-		return err.Error()
-	}
-	return fmt.Sprintf("panic: %v", p.reason)
-}
-
-func safelyCall(fn func(*Tx) error, tx *Tx) (err error) {
-	defer func() {
-		if p := recover(); p != nil {
-			err = panicked{p}
-		}
-	}()
-	return fn(tx)
-}
-
-// Sync executes fdatasync() against the database file handle.
-//
-// This is not necessary under normal operation, however, if you use NoSync
-// then it allows you to force the database file to sync against the disk.
-func (db *DB) Sync() error { return fdatasync(db) }
-
-// Stats retrieves ongoing performance stats for the database.
-// This is only updated when a transaction closes.
-func (db *DB) Stats() Stats {
-	db.statlock.RLock()
-	defer db.statlock.RUnlock()
-	return db.stats
-}
-
-// This is for internal access to the raw data bytes from the C cursor, use
-// carefully, or not at all.
-func (db *DB) Info() *Info {
-	return &Info{uintptr(unsafe.Pointer(&db.data[0])), db.pageSize}
-}
-
-// page retrieves a page reference from the mmap based on the current page size.
-func (db *DB) page(id pgid) *page {
-	pos := id * pgid(db.pageSize)
-	return (*page)(unsafe.Pointer(&db.data[pos]))
-}
-
-// pageInBuffer retrieves a page reference from a given byte array based on the current page size.
-func (db *DB) pageInBuffer(b []byte, id pgid) *page {
-	return (*page)(unsafe.Pointer(&b[id*pgid(db.pageSize)]))
-}
-
-// meta retrieves the current meta page reference.
-func (db *DB) meta() *meta {
-	// We have to return the meta with the highest txid which doesn't fail
-	// validation. Otherwise, we can cause errors when in fact the database is
-	// in a consistent state. metaA is the one with the higher txid.
-	metaA := db.meta0
-	metaB := db.meta1
-	if db.meta1.txid > db.meta0.txid {
-		metaA = db.meta1
-		metaB = db.meta0
-	}
-
-	// Use higher meta page if valid. Otherwise fallback to previous, if valid.
-	if err := metaA.validate(); err == nil {
-		return metaA
-	} else if err := metaB.validate(); err == nil {
-		return metaB
-	}
-
-	// This should never be reached, because both meta1 and meta0 were validated
-	// on mmap() and we do fsync() on every write.
-	panic("bolt.DB.meta(): invalid meta pages")
-}
-
-// allocate returns a contiguous block of memory starting at a given page.
-func (db *DB) allocate(txid txid, count int) (*page, error) {
-	// Allocate a temporary buffer for the page.
-	var buf []byte
-	if count == 1 {
-		buf = db.pagePool.Get().([]byte)
-	} else {
-		buf = make([]byte, count*db.pageSize)
-	}
-	p := (*page)(unsafe.Pointer(&buf[0]))
-	p.overflow = uint32(count - 1)
-
-	// Use pages from the freelist if they are available.
-	if p.id = db.freelist.allocate(txid, count); p.id != 0 {
-		return p, nil
-	}
-
-	// Resize mmap() if we're at the end.
-	p.id = db.rwtx.meta.pgid
-	var minsz = int((p.id+pgid(count))+1) * db.pageSize
-	if minsz >= db.datasz {
-		if err := db.mmap(minsz); err != nil {
-			return nil, fmt.Errorf("mmap allocate error: %s", err)
-		}
-	}
-
-	// Move the page id high water mark.
-	db.rwtx.meta.pgid += pgid(count)
-
-	return p, nil
-}
-
-// grow grows the size of the database to the given sz.
-func (db *DB) grow(sz int) error {
-	// Ignore if the new size is less than available file size.
-	if sz <= db.filesz {
-		return nil
-	}
-
-	// If the data is smaller than the alloc size then only allocate what's needed.
-	// Once it goes over the allocation size then allocate in chunks.
-	if db.datasz < db.AllocSize {
-		sz = db.datasz
-	} else {
-		sz += db.AllocSize
-	}
-
-	// Truncate and fsync to ensure file size metadata is flushed.
-	// https://github.com/boltdb/bolt/issues/284
-	if !db.NoGrowSync && !db.readOnly {
-		if runtime.GOOS != "windows" {
-			if err := db.file.Truncate(int64(sz)); err != nil {
-				return fmt.Errorf("file resize error: %s", err)
-			}
-		}
-		if err := db.file.Sync(); err != nil {
-			return fmt.Errorf("file sync error: %s", err)
-		}
-	}
-
-	db.filesz = sz
-	return nil
-}
-
-func (db *DB) IsReadOnly() bool {
-	return db.readOnly
-}
-
-func (db *DB) freepages() []pgid {
-	tx, err := db.beginTx()
-	defer func() {
-		err = tx.Rollback()
-		if err != nil {
-			panic("freepages: failed to rollback tx")
-		}
-	}()
-	if err != nil {
-		panic("freepages: failed to open read only tx")
-	}
-
-	reachable := make(map[pgid]*page)
-	nofreed := make(map[pgid]bool)
-	ech := make(chan error)
-	go func() {
-		for e := range ech {
-			panic(fmt.Sprintf("freepages: failed to get all reachable pages (%v)", e))
-		}
-	}()
-	tx.checkBucket(&tx.root, reachable, nofreed, ech)
-	close(ech)
-
-	var fids []pgid
-	for i := pgid(2); i < db.meta().pgid; i++ {
-		if _, ok := reachable[i]; !ok {
-			fids = append(fids, i)
-		}
-	}
-	return fids
-}
-
-// Options represents the options that can be set when opening a database.
-type Options struct {
-	// Timeout is the amount of time to wait to obtain a file lock.
-	// When set to zero it will wait indefinitely. This option is only
-	// available on Darwin and Linux.
-	Timeout time.Duration
-
-	// Sets the DB.NoGrowSync flag before memory mapping the file.
-	NoGrowSync bool
-
-	// Do not sync freelist to disk. This improves the database write performance
-	// under normal operation, but requires a full database re-sync during recovery.
-	NoFreelistSync bool
-
-	// FreelistType sets the backend freelist type. There are two options. Array which is simple but endures
-	// dramatic performance degradation if database is large and framentation in freelist is common.
-	// The alternative one is using hashmap, it is faster in almost all circumstances
-	// but it doesn't guarantee that it offers the smallest page id available. In normal case it is safe.
-	// The default type is array
-	FreelistType FreelistType
-
-	// Open database in read-only mode. Uses flock(..., LOCK_SH |LOCK_NB) to
-	// grab a shared lock (UNIX).
-	ReadOnly bool
-
-	// Sets the DB.MmapFlags flag before memory mapping the file.
-	MmapFlags int
-
-	// InitialMmapSize is the initial mmap size of the database
-	// in bytes. Read transactions won't block write transaction
-	// if the InitialMmapSize is large enough to hold database mmap
-	// size. (See DB.Begin for more information)
-	//
-	// If <=0, the initial map size is 0.
-	// If initialMmapSize is smaller than the previous database size,
-	// it takes no effect.
-	InitialMmapSize int
-
-	// PageSize overrides the default OS page size.
-	PageSize int
-
-	// NoSync sets the initial value of DB.NoSync. Normally this can just be
-	// set directly on the DB itself when returned from Open(), but this option
-	// is useful in APIs which expose Options but not the underlying DB.
-	NoSync bool
-
-	// OpenFile is used to open files. It defaults to os.OpenFile. This option
-	// is useful for writing hermetic tests.
-	OpenFile func(string, int, os.FileMode) (*os.File, error)
-}
-
-// DefaultOptions represent the options used if nil options are passed into Open().
-// No timeout is used which will cause Bolt to wait indefinitely for a lock.
-var DefaultOptions = &Options{
-	Timeout:      0,
-	NoGrowSync:   false,
-	FreelistType: FreelistArrayType,
-}
-
-// Stats represents statistics about the database.
-type Stats struct {
-	// Freelist stats
-	FreePageN     int // total number of free pages on the freelist
-	PendingPageN  int // total number of pending pages on the freelist
-	FreeAlloc     int // total bytes allocated in free pages
-	FreelistInuse int // total bytes used by the freelist
-
-	// Transaction stats
-	TxN     int // total number of started read transactions
-	OpenTxN int // number of currently open read transactions
-
-	TxStats TxStats // global, ongoing stats.
-}
-
-// Sub calculates and returns the difference between two sets of database stats.
-// This is useful when obtaining stats at two different points and time and
-// you need the performance counters that occurred within that time span.
-func (s *Stats) Sub(other *Stats) Stats {
-	if other == nil {
-		return *s
-	}
-	var diff Stats
-	diff.FreePageN = s.FreePageN
-	diff.PendingPageN = s.PendingPageN
-	diff.FreeAlloc = s.FreeAlloc
-	diff.FreelistInuse = s.FreelistInuse
-	diff.TxN = s.TxN - other.TxN
-	diff.TxStats = s.TxStats.Sub(&other.TxStats)
-	return diff
-}
-
-type Info struct {
-	Data     uintptr
-	PageSize int
-}
-
-type meta struct {
-	magic    uint32
-	version  uint32
-	pageSize uint32
-	flags    uint32
-	root     bucket
-	freelist pgid
-	pgid     pgid
-	txid     txid
-	checksum uint64
-}
-
-// validate checks the marker bytes and version of the meta page to ensure it matches this binary.
-func (m *meta) validate() error {
-	if m.magic != magic {
-		return ErrInvalid
-	} else if m.version != version {
-		return ErrVersionMismatch
-	} else if m.checksum != 0 && m.checksum != m.sum64() {
-		return ErrChecksum
-	}
-	return nil
-}
-
-// copy copies one meta object to another.
-func (m *meta) copy(dest *meta) {
-	*dest = *m
-}
-
-// write writes the meta onto a page.
-func (m *meta) write(p *page) {
-	if m.root.root >= m.pgid {
-		panic(fmt.Sprintf("root bucket pgid (%d) above high water mark (%d)", m.root.root, m.pgid))
-	} else if m.freelist >= m.pgid && m.freelist != pgidNoFreelist {
-		// TODO: reject pgidNoFreeList if !NoFreelistSync
-		panic(fmt.Sprintf("freelist pgid (%d) above high water mark (%d)", m.freelist, m.pgid))
-	}
-
-	// Page id is either going to be 0 or 1 which we can determine by the transaction ID.
-	p.id = pgid(m.txid % 2)
-	p.flags |= metaPageFlag
-
-	// Calculate the checksum.
-	m.checksum = m.sum64()
-
-	m.copy(p.meta())
-}
-
-// generates the checksum for the meta.
-func (m *meta) sum64() uint64 {
-	var h = fnv.New64a()
-	_, _ = h.Write((*[unsafe.Offsetof(meta{}.checksum)]byte)(unsafe.Pointer(m))[:])
-	return h.Sum64()
-}
-
-// _assert will panic with a given formatted message if the given condition is false.
-func _assert(condition bool, msg string, v ...interface{}) {
-	if !condition {
-		panic(fmt.Sprintf("assertion failed: "+msg, v...))
-	}
-}
diff --git a/vendor/github.com/etcd-io/bbolt/doc.go b/vendor/github.com/etcd-io/bbolt/doc.go
deleted file mode 100644
index 95f25f01c6..0000000000
--- a/vendor/github.com/etcd-io/bbolt/doc.go
+++ /dev/null
@@ -1,44 +0,0 @@
-/*
-package bbolt implements a low-level key/value store in pure Go. It supports
-fully serializable transactions, ACID semantics, and lock-free MVCC with
-multiple readers and a single writer. Bolt can be used for projects that
-want a simple data store without the need to add large dependencies such as
-Postgres or MySQL.
-
-Bolt is a single-level, zero-copy, B+tree data store. This means that Bolt is
-optimized for fast read access and does not require recovery in the event of a
-system crash. Transactions which have not finished committing will simply be
-rolled back in the event of a crash.
-
-The design of Bolt is based on Howard Chu's LMDB database project.
-
-Bolt currently works on Windows, Mac OS X, and Linux.
-
-
-Basics
-
-There are only a few types in Bolt: DB, Bucket, Tx, and Cursor. The DB is
-a collection of buckets and is represented by a single file on disk. A bucket is
-a collection of unique keys that are associated with values.
-
-Transactions provide either read-only or read-write access to the database.
-Read-only transactions can retrieve key/value pairs and can use Cursors to
-iterate over the dataset sequentially. Read-write transactions can create and
-delete buckets and can insert and remove keys. Only one read-write transaction
-is allowed at a time.
-
-
-Caveats
-
-The database uses a read-only, memory-mapped data file to ensure that
-applications cannot corrupt the database, however, this means that keys and
-values returned from Bolt cannot be changed. Writing to a read-only byte slice
-will cause Go to panic.
-
-Keys and values retrieved from the database are only valid for the life of
-the transaction. When used outside the transaction, these byte slices can
-point to different data or can point to invalid memory which will cause a panic.
-
-
-*/
-package bbolt
diff --git a/vendor/github.com/etcd-io/bbolt/errors.go b/vendor/github.com/etcd-io/bbolt/errors.go
deleted file mode 100644
index 48758ca577..0000000000
--- a/vendor/github.com/etcd-io/bbolt/errors.go
+++ /dev/null
@@ -1,71 +0,0 @@
-package bbolt
-
-import "errors"
-
-// These errors can be returned when opening or calling methods on a DB.
-var (
-	// ErrDatabaseNotOpen is returned when a DB instance is accessed before it
-	// is opened or after it is closed.
-	ErrDatabaseNotOpen = errors.New("database not open")
-
-	// ErrDatabaseOpen is returned when opening a database that is
-	// already open.
-	ErrDatabaseOpen = errors.New("database already open")
-
-	// ErrInvalid is returned when both meta pages on a database are invalid.
-	// This typically occurs when a file is not a bolt database.
-	ErrInvalid = errors.New("invalid database")
-
-	// ErrVersionMismatch is returned when the data file was created with a
-	// different version of Bolt.
-	ErrVersionMismatch = errors.New("version mismatch")
-
-	// ErrChecksum is returned when either meta page checksum does not match.
-	ErrChecksum = errors.New("checksum error")
-
-	// ErrTimeout is returned when a database cannot obtain an exclusive lock
-	// on the data file after the timeout passed to Open().
-	ErrTimeout = errors.New("timeout")
-)
-
-// These errors can occur when beginning or committing a Tx.
-var (
-	// ErrTxNotWritable is returned when performing a write operation on a
-	// read-only transaction.
-	ErrTxNotWritable = errors.New("tx not writable")
-
-	// ErrTxClosed is returned when committing or rolling back a transaction
-	// that has already been committed or rolled back.
-	ErrTxClosed = errors.New("tx closed")
-
-	// ErrDatabaseReadOnly is returned when a mutating transaction is started on a
-	// read-only database.
-	ErrDatabaseReadOnly = errors.New("database is in read-only mode")
-)
-
-// These errors can occur when putting or deleting a value or a bucket.
-var (
-	// ErrBucketNotFound is returned when trying to access a bucket that has
-	// not been created yet.
-	ErrBucketNotFound = errors.New("bucket not found")
-
-	// ErrBucketExists is returned when creating a bucket that already exists.
-	ErrBucketExists = errors.New("bucket already exists")
-
-	// ErrBucketNameRequired is returned when creating a bucket with a blank name.
-	ErrBucketNameRequired = errors.New("bucket name required")
-
-	// ErrKeyRequired is returned when inserting a zero-length key.
-	ErrKeyRequired = errors.New("key required")
-
-	// ErrKeyTooLarge is returned when inserting a key that is larger than MaxKeySize.
-	ErrKeyTooLarge = errors.New("key too large")
-
-	// ErrValueTooLarge is returned when inserting a value that is larger than MaxValueSize.
-	ErrValueTooLarge = errors.New("value too large")
-
-	// ErrIncompatibleValue is returned when trying create or delete a bucket
-	// on an existing non-bucket key or when trying to create or delete a
-	// non-bucket key on an existing bucket key.
-	ErrIncompatibleValue = errors.New("incompatible value")
-)
diff --git a/vendor/github.com/etcd-io/bbolt/freelist.go b/vendor/github.com/etcd-io/bbolt/freelist.go
deleted file mode 100644
index 587b8cc02d..0000000000
--- a/vendor/github.com/etcd-io/bbolt/freelist.go
+++ /dev/null
@@ -1,392 +0,0 @@
-package bbolt
-
-import (
-	"fmt"
-	"sort"
-	"unsafe"
-)
-
-// txPending holds a list of pgids and corresponding allocation txns
-// that are pending to be freed.
-type txPending struct {
-	ids              []pgid
-	alloctx          []txid // txids allocating the ids
-	lastReleaseBegin txid   // beginning txid of last matching releaseRange
-}
-
-// pidSet holds the set of starting pgids which have the same span size
-type pidSet map[pgid]struct{}
-
-// freelist represents a list of all pages that are available for allocation.
-// It also tracks pages that have been freed but are still in use by open transactions.
-type freelist struct {
-	freelistType   FreelistType                // freelist type
-	ids            []pgid                      // all free and available free page ids.
-	allocs         map[pgid]txid               // mapping of txid that allocated a pgid.
-	pending        map[txid]*txPending         // mapping of soon-to-be free page ids by tx.
-	cache          map[pgid]bool               // fast lookup of all free and pending page ids.
-	freemaps       map[uint64]pidSet           // key is the size of continuous pages(span), value is a set which contains the starting pgids of same size
-	forwardMap     map[pgid]uint64             // key is start pgid, value is its span size
-	backwardMap    map[pgid]uint64             // key is end pgid, value is its span size
-	allocate       func(txid txid, n int) pgid // the freelist allocate func
-	free_count     func() int                  // the function which gives you free page number
-	mergeSpans     func(ids pgids)             // the mergeSpan func
-	getFreePageIDs func() []pgid               // get free pgids func
-	readIDs        func(pgids []pgid)          // readIDs func reads list of pages and init the freelist
-}
-
-// newFreelist returns an empty, initialized freelist.
-func newFreelist(freelistType FreelistType) *freelist {
-	f := &freelist{
-		freelistType: freelistType,
-		allocs:       make(map[pgid]txid),
-		pending:      make(map[txid]*txPending),
-		cache:        make(map[pgid]bool),
-		freemaps:     make(map[uint64]pidSet),
-		forwardMap:   make(map[pgid]uint64),
-		backwardMap:  make(map[pgid]uint64),
-	}
-
-	if freelistType == FreelistMapType {
-		f.allocate = f.hashmapAllocate
-		f.free_count = f.hashmapFreeCount
-		f.mergeSpans = f.hashmapMergeSpans
-		f.getFreePageIDs = f.hashmapGetFreePageIDs
-		f.readIDs = f.hashmapReadIDs
-	} else {
-		f.allocate = f.arrayAllocate
-		f.free_count = f.arrayFreeCount
-		f.mergeSpans = f.arrayMergeSpans
-		f.getFreePageIDs = f.arrayGetFreePageIDs
-		f.readIDs = f.arrayReadIDs
-	}
-
-	return f
-}
-
-// size returns the size of the page after serialization.
-func (f *freelist) size() int {
-	n := f.count()
-	if n >= 0xFFFF {
-		// The first element will be used to store the count. See freelist.write.
-		n++
-	}
-	return pageHeaderSize + (int(unsafe.Sizeof(pgid(0))) * n)
-}
-
-// count returns count of pages on the freelist
-func (f *freelist) count() int {
-	return f.free_count() + f.pending_count()
-}
-
-// arrayFreeCount returns count of free pages(array version)
-func (f *freelist) arrayFreeCount() int {
-	return len(f.ids)
-}
-
-// pending_count returns count of pending pages
-func (f *freelist) pending_count() int {
-	var count int
-	for _, txp := range f.pending {
-		count += len(txp.ids)
-	}
-	return count
-}
-
-// copyall copies into dst a list of all free ids and all pending ids in one sorted list.
-// f.count returns the minimum length required for dst.
-func (f *freelist) copyall(dst []pgid) {
-	m := make(pgids, 0, f.pending_count())
-	for _, txp := range f.pending {
-		m = append(m, txp.ids...)
-	}
-	sort.Sort(m)
-	mergepgids(dst, f.getFreePageIDs(), m)
-}
-
-// arrayAllocate returns the starting page id of a contiguous list of pages of a given size.
-// If a contiguous block cannot be found then 0 is returned.
-func (f *freelist) arrayAllocate(txid txid, n int) pgid {
-	if len(f.ids) == 0 {
-		return 0
-	}
-
-	var initial, previd pgid
-	for i, id := range f.ids {
-		if id <= 1 {
-			panic(fmt.Sprintf("invalid page allocation: %d", id))
-		}
-
-		// Reset initial page if this is not contiguous.
-		if previd == 0 || id-previd != 1 {
-			initial = id
-		}
-
-		// If we found a contiguous block then remove it and return it.
-		if (id-initial)+1 == pgid(n) {
-			// If we're allocating off the beginning then take the fast path
-			// and just adjust the existing slice. This will use extra memory
-			// temporarily but the append() in free() will realloc the slice
-			// as is necessary.
-			if (i + 1) == n {
-				f.ids = f.ids[i+1:]
-			} else {
-				copy(f.ids[i-n+1:], f.ids[i+1:])
-				f.ids = f.ids[:len(f.ids)-n]
-			}
-
-			// Remove from the free cache.
-			for i := pgid(0); i < pgid(n); i++ {
-				delete(f.cache, initial+i)
-			}
-			f.allocs[initial] = txid
-			return initial
-		}
-
-		previd = id
-	}
-	return 0
-}
-
-// free releases a page and its overflow for a given transaction id.
-// If the page is already free then a panic will occur.
-func (f *freelist) free(txid txid, p *page) {
-	if p.id <= 1 {
-		panic(fmt.Sprintf("cannot free page 0 or 1: %d", p.id))
-	}
-
-	// Free page and all its overflow pages.
-	txp := f.pending[txid]
-	if txp == nil {
-		txp = &txPending{}
-		f.pending[txid] = txp
-	}
-	allocTxid, ok := f.allocs[p.id]
-	if ok {
-		delete(f.allocs, p.id)
-	} else if (p.flags & freelistPageFlag) != 0 {
-		// Freelist is always allocated by prior tx.
-		allocTxid = txid - 1
-	}
-
-	for id := p.id; id <= p.id+pgid(p.overflow); id++ {
-		// Verify that page is not already free.
-		if f.cache[id] {
-			panic(fmt.Sprintf("page %d already freed", id))
-		}
-		// Add to the freelist and cache.
-		txp.ids = append(txp.ids, id)
-		txp.alloctx = append(txp.alloctx, allocTxid)
-		f.cache[id] = true
-	}
-}
-
-// release moves all page ids for a transaction id (or older) to the freelist.
-func (f *freelist) release(txid txid) {
-	m := make(pgids, 0)
-	for tid, txp := range f.pending {
-		if tid <= txid {
-			// Move transaction's pending pages to the available freelist.
-			// Don't remove from the cache since the page is still free.
-			m = append(m, txp.ids...)
-			delete(f.pending, tid)
-		}
-	}
-	f.mergeSpans(m)
-}
-
-// releaseRange moves pending pages allocated within an extent [begin,end] to the free list.
-func (f *freelist) releaseRange(begin, end txid) {
-	if begin > end {
-		return
-	}
-	var m pgids
-	for tid, txp := range f.pending {
-		if tid < begin || tid > end {
-			continue
-		}
-		// Don't recompute freed pages if ranges haven't updated.
-		if txp.lastReleaseBegin == begin {
-			continue
-		}
-		for i := 0; i < len(txp.ids); i++ {
-			if atx := txp.alloctx[i]; atx < begin || atx > end {
-				continue
-			}
-			m = append(m, txp.ids[i])
-			txp.ids[i] = txp.ids[len(txp.ids)-1]
-			txp.ids = txp.ids[:len(txp.ids)-1]
-			txp.alloctx[i] = txp.alloctx[len(txp.alloctx)-1]
-			txp.alloctx = txp.alloctx[:len(txp.alloctx)-1]
-			i--
-		}
-		txp.lastReleaseBegin = begin
-		if len(txp.ids) == 0 {
-			delete(f.pending, tid)
-		}
-	}
-	f.mergeSpans(m)
-}
-
-// rollback removes the pages from a given pending tx.
-func (f *freelist) rollback(txid txid) {
-	// Remove page ids from cache.
-	txp := f.pending[txid]
-	if txp == nil {
-		return
-	}
-	var m pgids
-	for i, pgid := range txp.ids {
-		delete(f.cache, pgid)
-		tx := txp.alloctx[i]
-		if tx == 0 {
-			continue
-		}
-		if tx != txid {
-			// Pending free aborted; restore page back to alloc list.
-			f.allocs[pgid] = tx
-		} else {
-			// Freed page was allocated by this txn; OK to throw away.
-			m = append(m, pgid)
-		}
-	}
-	// Remove pages from pending list and mark as free if allocated by txid.
-	delete(f.pending, txid)
-	f.mergeSpans(m)
-}
-
-// freed returns whether a given page is in the free list.
-func (f *freelist) freed(pgid pgid) bool {
-	return f.cache[pgid]
-}
-
-// read initializes the freelist from a freelist page.
-func (f *freelist) read(p *page) {
-	if (p.flags & freelistPageFlag) == 0 {
-		panic(fmt.Sprintf("invalid freelist page: %d, page type is %s", p.id, p.typ()))
-	}
-	// If the page.count is at the max uint16 value (64k) then it's considered
-	// an overflow and the size of the freelist is stored as the first element.
-	idx, count := 0, int(p.count)
-	if count == 0xFFFF {
-		idx = 1
-		count = int(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[0])
-	}
-
-	// Copy the list of page ids from the freelist.
-	if count == 0 {
-		f.ids = nil
-	} else {
-		ids := ((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[idx : idx+count]
-
-		// copy the ids, so we don't modify on the freelist page directly
-		idsCopy := make([]pgid, count)
-		copy(idsCopy, ids)
-		// Make sure they're sorted.
-		sort.Sort(pgids(idsCopy))
-
-		f.readIDs(idsCopy)
-	}
-}
-
-// arrayReadIDs initializes the freelist from a given list of ids.
-func (f *freelist) arrayReadIDs(ids []pgid) {
-	f.ids = ids
-	f.reindex()
-}
-
-func (f *freelist) arrayGetFreePageIDs() []pgid {
-	return f.ids
-}
-
-// write writes the page ids onto a freelist page. All free and pending ids are
-// saved to disk since in the event of a program crash, all pending ids will
-// become free.
-func (f *freelist) write(p *page) error {
-	// Combine the old free pgids and pgids waiting on an open transaction.
-
-	// Update the header flag.
-	p.flags |= freelistPageFlag
-
-	// The page.count can only hold up to 64k elements so if we overflow that
-	// number then we handle it by putting the size in the first element.
-	lenids := f.count()
-	if lenids == 0 {
-		p.count = uint16(lenids)
-	} else if lenids < 0xFFFF {
-		p.count = uint16(lenids)
-		f.copyall(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[:])
-	} else {
-		p.count = 0xFFFF
-		((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[0] = pgid(lenids)
-		f.copyall(((*[maxAllocSize]pgid)(unsafe.Pointer(&p.ptr)))[1:])
-	}
-
-	return nil
-}
-
-// reload reads the freelist from a page and filters out pending items.
-func (f *freelist) reload(p *page) {
-	f.read(p)
-
-	// Build a cache of only pending pages.
-	pcache := make(map[pgid]bool)
-	for _, txp := range f.pending {
-		for _, pendingID := range txp.ids {
-			pcache[pendingID] = true
-		}
-	}
-
-	// Check each page in the freelist and build a new available freelist
-	// with any pages not in the pending lists.
-	var a []pgid
-	for _, id := range f.getFreePageIDs() {
-		if !pcache[id] {
-			a = append(a, id)
-		}
-	}
-
-	f.readIDs(a)
-}
-
-// noSyncReload reads the freelist from pgids and filters out pending items.
-func (f *freelist) noSyncReload(pgids []pgid) {
-	// Build a cache of only pending pages.
-	pcache := make(map[pgid]bool)
-	for _, txp := range f.pending {
-		for _, pendingID := range txp.ids {
-			pcache[pendingID] = true
-		}
-	}
-
-	// Check each page in the freelist and build a new available freelist
-	// with any pages not in the pending lists.
-	var a []pgid
-	for _, id := range pgids {
-		if !pcache[id] {
-			a = append(a, id)
-		}
-	}
-
-	f.readIDs(a)
-}
-
-// reindex rebuilds the free cache based on available and pending free lists.
-func (f *freelist) reindex() {
-	ids := f.getFreePageIDs()
-	f.cache = make(map[pgid]bool, len(ids))
-	for _, id := range ids {
-		f.cache[id] = true
-	}
-	for _, txp := range f.pending {
-		for _, pendingID := range txp.ids {
-			f.cache[pendingID] = true
-		}
-	}
-}
-
-// arrayMergeSpans try to merge list of pages(represented by pgids) with existing spans but using array
-func (f *freelist) arrayMergeSpans(ids pgids) {
-	sort.Sort(ids)
-	f.ids = pgids(f.ids).merge(ids)
-}
diff --git a/vendor/github.com/etcd-io/bbolt/freelist_hmap.go b/vendor/github.com/etcd-io/bbolt/freelist_hmap.go
deleted file mode 100644
index 6a03a6c3c8..0000000000
--- a/vendor/github.com/etcd-io/bbolt/freelist_hmap.go
+++ /dev/null
@@ -1,178 +0,0 @@
-package bbolt
-
-import "sort"
-
-// hashmapFreeCount returns count of free pages(hashmap version)
-func (f *freelist) hashmapFreeCount() int {
-	// use the forwardmap to get the total count
-	count := 0
-	for _, size := range f.forwardMap {
-		count += int(size)
-	}
-	return count
-}
-
-// hashmapAllocate serves the same purpose as arrayAllocate, but use hashmap as backend
-func (f *freelist) hashmapAllocate(txid txid, n int) pgid {
-	if n == 0 {
-		return 0
-	}
-
-	// if we have a exact size match just return short path
-	if bm, ok := f.freemaps[uint64(n)]; ok {
-		for pid := range bm {
-			// remove the span
-			f.delSpan(pid, uint64(n))
-
-			f.allocs[pid] = txid
-
-			for i := pgid(0); i < pgid(n); i++ {
-				delete(f.cache, pid+pgid(i))
-			}
-			return pid
-		}
-	}
-
-	// lookup the map to find larger span
-	for size, bm := range f.freemaps {
-		if size < uint64(n) {
-			continue
-		}
-
-		for pid := range bm {
-			// remove the initial
-			f.delSpan(pid, uint64(size))
-
-			f.allocs[pid] = txid
-
-			remain := size - uint64(n)
-
-			// add remain span
-			f.addSpan(pid+pgid(n), remain)
-
-			for i := pgid(0); i < pgid(n); i++ {
-				delete(f.cache, pid+pgid(i))
-			}
-			return pid
-		}
-	}
-
-	return 0
-}
-
-// hashmapReadIDs reads pgids as input an initial the freelist(hashmap version)
-func (f *freelist) hashmapReadIDs(pgids []pgid) {
-	f.init(pgids)
-
-	// Rebuild the page cache.
-	f.reindex()
-}
-
-// hashmapGetFreePageIDs returns the sorted free page ids
-func (f *freelist) hashmapGetFreePageIDs() []pgid {
-	count := f.free_count()
-	if count == 0 {
-		return nil
-	}
-
-	m := make([]pgid, 0, count)
-	for start, size := range f.forwardMap {
-		for i := 0; i < int(size); i++ {
-			m = append(m, start+pgid(i))
-		}
-	}
-	sort.Sort(pgids(m))
-
-	return m
-}
-
-// hashmapMergeSpans try to merge list of pages(represented by pgids) with existing spans
-func (f *freelist) hashmapMergeSpans(ids pgids) {
-	for _, id := range ids {
-		// try to see if we can merge and update
-		f.mergeWithExistingSpan(id)
-	}
-}
-
-// mergeWithExistingSpan merges pid to the existing free spans, try to merge it backward and forward
-func (f *freelist) mergeWithExistingSpan(pid pgid) {
-	prev := pid - 1
-	next := pid + 1
-
-	preSize, mergeWithPrev := f.backwardMap[prev]
-	nextSize, mergeWithNext := f.forwardMap[next]
-	newStart := pid
-	newSize := uint64(1)
-
-	if mergeWithPrev {
-		//merge with previous span
-		start := prev + 1 - pgid(preSize)
-		f.delSpan(start, preSize)
-
-		newStart -= pgid(preSize)
-		newSize += preSize
-	}
-
-	if mergeWithNext {
-		// merge with next span
-		f.delSpan(next, nextSize)
-		newSize += nextSize
-	}
-
-	f.addSpan(newStart, newSize)
-}
-
-func (f *freelist) addSpan(start pgid, size uint64) {
-	f.backwardMap[start-1+pgid(size)] = size
-	f.forwardMap[start] = size
-	if _, ok := f.freemaps[size]; !ok {
-		f.freemaps[size] = make(map[pgid]struct{})
-	}
-
-	f.freemaps[size][start] = struct{}{}
-}
-
-func (f *freelist) delSpan(start pgid, size uint64) {
-	delete(f.forwardMap, start)
-	delete(f.backwardMap, start+pgid(size-1))
-	delete(f.freemaps[size], start)
-	if len(f.freemaps[size]) == 0 {
-		delete(f.freemaps, size)
-	}
-}
-
-// initial from pgids using when use hashmap version
-// pgids must be sorted
-func (f *freelist) init(pgids []pgid) {
-	if len(pgids) == 0 {
-		return
-	}
-
-	size := uint64(1)
-	start := pgids[0]
-
-	if !sort.SliceIsSorted([]pgid(pgids), func(i, j int) bool { return pgids[i] < pgids[j] }) {
-		panic("pgids not sorted")
-	}
-
-	f.freemaps = make(map[uint64]pidSet)
-	f.forwardMap = make(map[pgid]uint64)
-	f.backwardMap = make(map[pgid]uint64)
-
-	for i := 1; i < len(pgids); i++ {
-		// continuous page
-		if pgids[i] == pgids[i-1]+1 {
-			size++
-		} else {
-			f.addSpan(start, size)
-
-			size = 1
-			start = pgids[i]
-		}
-	}
-
-	// init the tail
-	if size != 0 && start != 0 {
-		f.addSpan(start, size)
-	}
-}
diff --git a/vendor/github.com/etcd-io/bbolt/node.go b/vendor/github.com/etcd-io/bbolt/node.go
deleted file mode 100644
index 6c3fa553ea..0000000000
--- a/vendor/github.com/etcd-io/bbolt/node.go
+++ /dev/null
@@ -1,604 +0,0 @@
-package bbolt
-
-import (
-	"bytes"
-	"fmt"
-	"sort"
-	"unsafe"
-)
-
-// node represents an in-memory, deserialized page.
-type node struct {
-	bucket     *Bucket
-	isLeaf     bool
-	unbalanced bool
-	spilled    bool
-	key        []byte
-	pgid       pgid
-	parent     *node
-	children   nodes
-	inodes     inodes
-}
-
-// root returns the top-level node this node is attached to.
-func (n *node) root() *node {
-	if n.parent == nil {
-		return n
-	}
-	return n.parent.root()
-}
-
-// minKeys returns the minimum number of inodes this node should have.
-func (n *node) minKeys() int {
-	if n.isLeaf {
-		return 1
-	}
-	return 2
-}
-
-// size returns the size of the node after serialization.
-func (n *node) size() int {
-	sz, elsz := pageHeaderSize, n.pageElementSize()
-	for i := 0; i < len(n.inodes); i++ {
-		item := &n.inodes[i]
-		sz += elsz + len(item.key) + len(item.value)
-	}
-	return sz
-}
-
-// sizeLessThan returns true if the node is less than a given size.
-// This is an optimization to avoid calculating a large node when we only need
-// to know if it fits inside a certain page size.
-func (n *node) sizeLessThan(v int) bool {
-	sz, elsz := pageHeaderSize, n.pageElementSize()
-	for i := 0; i < len(n.inodes); i++ {
-		item := &n.inodes[i]
-		sz += elsz + len(item.key) + len(item.value)
-		if sz >= v {
-			return false
-		}
-	}
-	return true
-}
-
-// pageElementSize returns the size of each page element based on the type of node.
-func (n *node) pageElementSize() int {
-	if n.isLeaf {
-		return leafPageElementSize
-	}
-	return branchPageElementSize
-}
-
-// childAt returns the child node at a given index.
-func (n *node) childAt(index int) *node {
-	if n.isLeaf {
-		panic(fmt.Sprintf("invalid childAt(%d) on a leaf node", index))
-	}
-	return n.bucket.node(n.inodes[index].pgid, n)
-}
-
-// childIndex returns the index of a given child node.
-func (n *node) childIndex(child *node) int {
-	index := sort.Search(len(n.inodes), func(i int) bool { return bytes.Compare(n.inodes[i].key, child.key) != -1 })
-	return index
-}
-
-// numChildren returns the number of children.
-func (n *node) numChildren() int {
-	return len(n.inodes)
-}
-
-// nextSibling returns the next node with the same parent.
-func (n *node) nextSibling() *node {
-	if n.parent == nil {
-		return nil
-	}
-	index := n.parent.childIndex(n)
-	if index >= n.parent.numChildren()-1 {
-		return nil
-	}
-	return n.parent.childAt(index + 1)
-}
-
-// prevSibling returns the previous node with the same parent.
-func (n *node) prevSibling() *node {
-	if n.parent == nil {
-		return nil
-	}
-	index := n.parent.childIndex(n)
-	if index == 0 {
-		return nil
-	}
-	return n.parent.childAt(index - 1)
-}
-
-// put inserts a key/value.
-func (n *node) put(oldKey, newKey, value []byte, pgid pgid, flags uint32) {
-	if pgid >= n.bucket.tx.meta.pgid {
-		panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", pgid, n.bucket.tx.meta.pgid))
-	} else if len(oldKey) <= 0 {
-		panic("put: zero-length old key")
-	} else if len(newKey) <= 0 {
-		panic("put: zero-length new key")
-	}
-
-	// Find insertion index.
-	index := sort.Search(len(n.inodes), func(i int) bool { return bytes.Compare(n.inodes[i].key, oldKey) != -1 })
-
-	// Add capacity and shift nodes if we don't have an exact match and need to insert.
-	exact := (len(n.inodes) > 0 && index < len(n.inodes) && bytes.Equal(n.inodes[index].key, oldKey))
-	if !exact {
-		n.inodes = append(n.inodes, inode{})
-		copy(n.inodes[index+1:], n.inodes[index:])
-	}
-
-	inode := &n.inodes[index]
-	inode.flags = flags
-	inode.key = newKey
-	inode.value = value
-	inode.pgid = pgid
-	_assert(len(inode.key) > 0, "put: zero-length inode key")
-}
-
-// del removes a key from the node.
-func (n *node) del(key []byte) {
-	// Find index of key.
-	index := sort.Search(len(n.inodes), func(i int) bool { return bytes.Compare(n.inodes[i].key, key) != -1 })
-
-	// Exit if the key isn't found.
-	if index >= len(n.inodes) || !bytes.Equal(n.inodes[index].key, key) {
-		return
-	}
-
-	// Delete inode from the node.
-	n.inodes = append(n.inodes[:index], n.inodes[index+1:]...)
-
-	// Mark the node as needing rebalancing.
-	n.unbalanced = true
-}
-
-// read initializes the node from a page.
-func (n *node) read(p *page) {
-	n.pgid = p.id
-	n.isLeaf = ((p.flags & leafPageFlag) != 0)
-	n.inodes = make(inodes, int(p.count))
-
-	for i := 0; i < int(p.count); i++ {
-		inode := &n.inodes[i]
-		if n.isLeaf {
-			elem := p.leafPageElement(uint16(i))
-			inode.flags = elem.flags
-			inode.key = elem.key()
-			inode.value = elem.value()
-		} else {
-			elem := p.branchPageElement(uint16(i))
-			inode.pgid = elem.pgid
-			inode.key = elem.key()
-		}
-		_assert(len(inode.key) > 0, "read: zero-length inode key")
-	}
-
-	// Save first key so we can find the node in the parent when we spill.
-	if len(n.inodes) > 0 {
-		n.key = n.inodes[0].key
-		_assert(len(n.key) > 0, "read: zero-length node key")
-	} else {
-		n.key = nil
-	}
-}
-
-// write writes the items onto one or more pages.
-func (n *node) write(p *page) {
-	// Initialize page.
-	if n.isLeaf {
-		p.flags |= leafPageFlag
-	} else {
-		p.flags |= branchPageFlag
-	}
-
-	if len(n.inodes) >= 0xFFFF {
-		panic(fmt.Sprintf("inode overflow: %d (pgid=%d)", len(n.inodes), p.id))
-	}
-	p.count = uint16(len(n.inodes))
-
-	// Stop here if there are no items to write.
-	if p.count == 0 {
-		return
-	}
-
-	// Loop over each item and write it to the page.
-	b := (*[maxAllocSize]byte)(unsafe.Pointer(&p.ptr))[n.pageElementSize()*len(n.inodes):]
-	for i, item := range n.inodes {
-		_assert(len(item.key) > 0, "write: zero-length inode key")
-
-		// Write the page element.
-		if n.isLeaf {
-			elem := p.leafPageElement(uint16(i))
-			elem.pos = uint32(uintptr(unsafe.Pointer(&b[0])) - uintptr(unsafe.Pointer(elem)))
-			elem.flags = item.flags
-			elem.ksize = uint32(len(item.key))
-			elem.vsize = uint32(len(item.value))
-		} else {
-			elem := p.branchPageElement(uint16(i))
-			elem.pos = uint32(uintptr(unsafe.Pointer(&b[0])) - uintptr(unsafe.Pointer(elem)))
-			elem.ksize = uint32(len(item.key))
-			elem.pgid = item.pgid
-			_assert(elem.pgid != p.id, "write: circular dependency occurred")
-		}
-
-		// If the length of key+value is larger than the max allocation size
-		// then we need to reallocate the byte array pointer.
-		//
-		// See: https://github.com/boltdb/bolt/pull/335
-		klen, vlen := len(item.key), len(item.value)
-		if len(b) < klen+vlen {
-			b = (*[maxAllocSize]byte)(unsafe.Pointer(&b[0]))[:]
-		}
-
-		// Write data for the element to the end of the page.
-		copy(b[0:], item.key)
-		b = b[klen:]
-		copy(b[0:], item.value)
-		b = b[vlen:]
-	}
-
-	// DEBUG ONLY: n.dump()
-}
-
-// split breaks up a node into multiple smaller nodes, if appropriate.
-// This should only be called from the spill() function.
-func (n *node) split(pageSize int) []*node {
-	var nodes []*node
-
-	node := n
-	for {
-		// Split node into two.
-		a, b := node.splitTwo(pageSize)
-		nodes = append(nodes, a)
-
-		// If we can't split then exit the loop.
-		if b == nil {
-			break
-		}
-
-		// Set node to b so it gets split on the next iteration.
-		node = b
-	}
-
-	return nodes
-}
-
-// splitTwo breaks up a node into two smaller nodes, if appropriate.
-// This should only be called from the split() function.
-func (n *node) splitTwo(pageSize int) (*node, *node) {
-	// Ignore the split if the page doesn't have at least enough nodes for
-	// two pages or if the nodes can fit in a single page.
-	if len(n.inodes) <= (minKeysPerPage*2) || n.sizeLessThan(pageSize) {
-		return n, nil
-	}
-
-	// Determine the threshold before starting a new node.
-	var fillPercent = n.bucket.FillPercent
-	if fillPercent < minFillPercent {
-		fillPercent = minFillPercent
-	} else if fillPercent > maxFillPercent {
-		fillPercent = maxFillPercent
-	}
-	threshold := int(float64(pageSize) * fillPercent)
-
-	// Determine split position and sizes of the two pages.
-	splitIndex, _ := n.splitIndex(threshold)
-
-	// Split node into two separate nodes.
-	// If there's no parent then we'll need to create one.
-	if n.parent == nil {
-		n.parent = &node{bucket: n.bucket, children: []*node{n}}
-	}
-
-	// Create a new node and add it to the parent.
-	next := &node{bucket: n.bucket, isLeaf: n.isLeaf, parent: n.parent}
-	n.parent.children = append(n.parent.children, next)
-
-	// Split inodes across two nodes.
-	next.inodes = n.inodes[splitIndex:]
-	n.inodes = n.inodes[:splitIndex]
-
-	// Update the statistics.
-	n.bucket.tx.stats.Split++
-
-	return n, next
-}
-
-// splitIndex finds the position where a page will fill a given threshold.
-// It returns the index as well as the size of the first page.
-// This is only be called from split().
-func (n *node) splitIndex(threshold int) (index, sz int) {
-	sz = pageHeaderSize
-
-	// Loop until we only have the minimum number of keys required for the second page.
-	for i := 0; i < len(n.inodes)-minKeysPerPage; i++ {
-		index = i
-		inode := n.inodes[i]
-		elsize := n.pageElementSize() + len(inode.key) + len(inode.value)
-
-		// If we have at least the minimum number of keys and adding another
-		// node would put us over the threshold then exit and return.
-		if i >= minKeysPerPage && sz+elsize > threshold {
-			break
-		}
-
-		// Add the element size to the total size.
-		sz += elsize
-	}
-
-	return
-}
-
-// spill writes the nodes to dirty pages and splits nodes as it goes.
-// Returns an error if dirty pages cannot be allocated.
-func (n *node) spill() error {
-	var tx = n.bucket.tx
-	if n.spilled {
-		return nil
-	}
-
-	// Spill child nodes first. Child nodes can materialize sibling nodes in
-	// the case of split-merge so we cannot use a range loop. We have to check
-	// the children size on every loop iteration.
-	sort.Sort(n.children)
-	for i := 0; i < len(n.children); i++ {
-		if err := n.children[i].spill(); err != nil {
-			return err
-		}
-	}
-
-	// We no longer need the child list because it's only used for spill tracking.
-	n.children = nil
-
-	// Split nodes into appropriate sizes. The first node will always be n.
-	var nodes = n.split(tx.db.pageSize)
-	for _, node := range nodes {
-		// Add node's page to the freelist if it's not new.
-		if node.pgid > 0 {
-			tx.db.freelist.free(tx.meta.txid, tx.page(node.pgid))
-			node.pgid = 0
-		}
-
-		// Allocate contiguous space for the node.
-		p, err := tx.allocate((node.size() + tx.db.pageSize - 1) / tx.db.pageSize)
-		if err != nil {
-			return err
-		}
-
-		// Write the node.
-		if p.id >= tx.meta.pgid {
-			panic(fmt.Sprintf("pgid (%d) above high water mark (%d)", p.id, tx.meta.pgid))
-		}
-		node.pgid = p.id
-		node.write(p)
-		node.spilled = true
-
-		// Insert into parent inodes.
-		if node.parent != nil {
-			var key = node.key
-			if key == nil {
-				key = node.inodes[0].key
-			}
-
-			node.parent.put(key, node.inodes[0].key, nil, node.pgid, 0)
-			node.key = node.inodes[0].key
-			_assert(len(node.key) > 0, "spill: zero-length node key")
-		}
-
-		// Update the statistics.
-		tx.stats.Spill++
-	}
-
-	// If the root node split and created a new root then we need to spill that
-	// as well. We'll clear out the children to make sure it doesn't try to respill.
-	if n.parent != nil && n.parent.pgid == 0 {
-		n.children = nil
-		return n.parent.spill()
-	}
-
-	return nil
-}
-
-// rebalance attempts to combine the node with sibling nodes if the node fill
-// size is below a threshold or if there are not enough keys.
-func (n *node) rebalance() {
-	if !n.unbalanced {
-		return
-	}
-	n.unbalanced = false
-
-	// Update statistics.
-	n.bucket.tx.stats.Rebalance++
-
-	// Ignore if node is above threshold (25%) and has enough keys.
-	var threshold = n.bucket.tx.db.pageSize / 4
-	if n.size() > threshold && len(n.inodes) > n.minKeys() {
-		return
-	}
-
-	// Root node has special handling.
-	if n.parent == nil {
-		// If root node is a branch and only has one node then collapse it.
-		if !n.isLeaf && len(n.inodes) == 1 {
-			// Move root's child up.
-			child := n.bucket.node(n.inodes[0].pgid, n)
-			n.isLeaf = child.isLeaf
-			n.inodes = child.inodes[:]
-			n.children = child.children
-
-			// Reparent all child nodes being moved.
-			for _, inode := range n.inodes {
-				if child, ok := n.bucket.nodes[inode.pgid]; ok {
-					child.parent = n
-				}
-			}
-
-			// Remove old child.
-			child.parent = nil
-			delete(n.bucket.nodes, child.pgid)
-			child.free()
-		}
-
-		return
-	}
-
-	// If node has no keys then just remove it.
-	if n.numChildren() == 0 {
-		n.parent.del(n.key)
-		n.parent.removeChild(n)
-		delete(n.bucket.nodes, n.pgid)
-		n.free()
-		n.parent.rebalance()
-		return
-	}
-
-	_assert(n.parent.numChildren() > 1, "parent must have at least 2 children")
-
-	// Destination node is right sibling if idx == 0, otherwise left sibling.
-	var target *node
-	var useNextSibling = (n.parent.childIndex(n) == 0)
-	if useNextSibling {
-		target = n.nextSibling()
-	} else {
-		target = n.prevSibling()
-	}
-
-	// If both this node and the target node are too small then merge them.
-	if useNextSibling {
-		// Reparent all child nodes being moved.
-		for _, inode := range target.inodes {
-			if child, ok := n.bucket.nodes[inode.pgid]; ok {
-				child.parent.removeChild(child)
-				child.parent = n
-				child.parent.children = append(child.parent.children, child)
-			}
-		}
-
-		// Copy over inodes from target and remove target.
-		n.inodes = append(n.inodes, target.inodes...)
-		n.parent.del(target.key)
-		n.parent.removeChild(target)
-		delete(n.bucket.nodes, target.pgid)
-		target.free()
-	} else {
-		// Reparent all child nodes being moved.
-		for _, inode := range n.inodes {
-			if child, ok := n.bucket.nodes[inode.pgid]; ok {
-				child.parent.removeChild(child)
-				child.parent = target
-				child.parent.children = append(child.parent.children, child)
-			}
-		}
-
-		// Copy over inodes to target and remove node.
-		target.inodes = append(target.inodes, n.inodes...)
-		n.parent.del(n.key)
-		n.parent.removeChild(n)
-		delete(n.bucket.nodes, n.pgid)
-		n.free()
-	}
-
-	// Either this node or the target node was deleted from the parent so rebalance it.
-	n.parent.rebalance()
-}
-
-// removes a node from the list of in-memory children.
-// This does not affect the inodes.
-func (n *node) removeChild(target *node) {
-	for i, child := range n.children {
-		if child == target {
-			n.children = append(n.children[:i], n.children[i+1:]...)
-			return
-		}
-	}
-}
-
-// dereference causes the node to copy all its inode key/value references to heap memory.
-// This is required when the mmap is reallocated so inodes are not pointing to stale data.
-func (n *node) dereference() {
-	if n.key != nil {
-		key := make([]byte, len(n.key))
-		copy(key, n.key)
-		n.key = key
-		_assert(n.pgid == 0 || len(n.key) > 0, "dereference: zero-length node key on existing node")
-	}
-
-	for i := range n.inodes {
-		inode := &n.inodes[i]
-
-		key := make([]byte, len(inode.key))
-		copy(key, inode.key)
-		inode.key = key
-		_assert(len(inode.key) > 0, "dereference: zero-length inode key")
-
-		value := make([]byte, len(inode.value))
-		copy(value, inode.value)
-		inode.value = value
-	}
-
-	// Recursively dereference children.
-	for _, child := range n.children {
-		child.dereference()
-	}
-
-	// Update statistics.
-	n.bucket.tx.stats.NodeDeref++
-}
-
-// free adds the node's underlying page to the freelist.
-func (n *node) free() {
-	if n.pgid != 0 {
-		n.bucket.tx.db.freelist.free(n.bucket.tx.meta.txid, n.bucket.tx.page(n.pgid))
-		n.pgid = 0
-	}
-}
-
-// dump writes the contents of the node to STDERR for debugging purposes.
-/*
-func (n *node) dump() {
-	// Write node header.
-	var typ = "branch"
-	if n.isLeaf {
-		typ = "leaf"
-	}
-	warnf("[NODE %d {type=%s count=%d}]", n.pgid, typ, len(n.inodes))
-
-	// Write out abbreviated version of each item.
-	for _, item := range n.inodes {
-		if n.isLeaf {
-			if item.flags&bucketLeafFlag != 0 {
-				bucket := (*bucket)(unsafe.Pointer(&item.value[0]))
-				warnf("+L %08x -> (bucket root=%d)", trunc(item.key, 4), bucket.root)
-			} else {
-				warnf("+L %08x -> %08x", trunc(item.key, 4), trunc(item.value, 4))
-			}
-		} else {
-			warnf("+B %08x -> pgid=%d", trunc(item.key, 4), item.pgid)
-		}
-	}
-	warn("")
-}
-*/
-
-type nodes []*node
-
-func (s nodes) Len() int           { return len(s) }
-func (s nodes) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-func (s nodes) Less(i, j int) bool { return bytes.Compare(s[i].inodes[0].key, s[j].inodes[0].key) == -1 }
-
-// inode represents an internal node inside of a node.
-// It can be used to point to elements in a page or point
-// to an element which hasn't been added to a page yet.
-type inode struct {
-	flags uint32
-	pgid  pgid
-	key   []byte
-	value []byte
-}
-
-type inodes []inode
diff --git a/vendor/github.com/etcd-io/bbolt/page.go b/vendor/github.com/etcd-io/bbolt/page.go
deleted file mode 100644
index bca9615f0f..0000000000
--- a/vendor/github.com/etcd-io/bbolt/page.go
+++ /dev/null
@@ -1,197 +0,0 @@
-package bbolt
-
-import (
-	"fmt"
-	"os"
-	"sort"
-	"unsafe"
-)
-
-const pageHeaderSize = int(unsafe.Offsetof(((*page)(nil)).ptr))
-
-const minKeysPerPage = 2
-
-const branchPageElementSize = int(unsafe.Sizeof(branchPageElement{}))
-const leafPageElementSize = int(unsafe.Sizeof(leafPageElement{}))
-
-const (
-	branchPageFlag   = 0x01
-	leafPageFlag     = 0x02
-	metaPageFlag     = 0x04
-	freelistPageFlag = 0x10
-)
-
-const (
-	bucketLeafFlag = 0x01
-)
-
-type pgid uint64
-
-type page struct {
-	id       pgid
-	flags    uint16
-	count    uint16
-	overflow uint32
-	ptr      uintptr
-}
-
-// typ returns a human readable page type string used for debugging.
-func (p *page) typ() string {
-	if (p.flags & branchPageFlag) != 0 {
-		return "branch"
-	} else if (p.flags & leafPageFlag) != 0 {
-		return "leaf"
-	} else if (p.flags & metaPageFlag) != 0 {
-		return "meta"
-	} else if (p.flags & freelistPageFlag) != 0 {
-		return "freelist"
-	}
-	return fmt.Sprintf("unknown<%02x>", p.flags)
-}
-
-// meta returns a pointer to the metadata section of the page.
-func (p *page) meta() *meta {
-	return (*meta)(unsafe.Pointer(&p.ptr))
-}
-
-// leafPageElement retrieves the leaf node by index
-func (p *page) leafPageElement(index uint16) *leafPageElement {
-	n := &((*[0x7FFFFFF]leafPageElement)(unsafe.Pointer(&p.ptr)))[index]
-	return n
-}
-
-// leafPageElements retrieves a list of leaf nodes.
-func (p *page) leafPageElements() []leafPageElement {
-	if p.count == 0 {
-		return nil
-	}
-	return ((*[0x7FFFFFF]leafPageElement)(unsafe.Pointer(&p.ptr)))[:]
-}
-
-// branchPageElement retrieves the branch node by index
-func (p *page) branchPageElement(index uint16) *branchPageElement {
-	return &((*[0x7FFFFFF]branchPageElement)(unsafe.Pointer(&p.ptr)))[index]
-}
-
-// branchPageElements retrieves a list of branch nodes.
-func (p *page) branchPageElements() []branchPageElement {
-	if p.count == 0 {
-		return nil
-	}
-	return ((*[0x7FFFFFF]branchPageElement)(unsafe.Pointer(&p.ptr)))[:]
-}
-
-// dump writes n bytes of the page to STDERR as hex output.
-func (p *page) hexdump(n int) {
-	buf := (*[maxAllocSize]byte)(unsafe.Pointer(p))[:n]
-	fmt.Fprintf(os.Stderr, "%x\n", buf)
-}
-
-type pages []*page
-
-func (s pages) Len() int           { return len(s) }
-func (s pages) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-func (s pages) Less(i, j int) bool { return s[i].id < s[j].id }
-
-// branchPageElement represents a node on a branch page.
-type branchPageElement struct {
-	pos   uint32
-	ksize uint32
-	pgid  pgid
-}
-
-// key returns a byte slice of the node key.
-func (n *branchPageElement) key() []byte {
-	buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
-	return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos]))[:n.ksize]
-}
-
-// leafPageElement represents a node on a leaf page.
-type leafPageElement struct {
-	flags uint32
-	pos   uint32
-	ksize uint32
-	vsize uint32
-}
-
-// key returns a byte slice of the node key.
-func (n *leafPageElement) key() []byte {
-	buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
-	return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos]))[:n.ksize:n.ksize]
-}
-
-// value returns a byte slice of the node value.
-func (n *leafPageElement) value() []byte {
-	buf := (*[maxAllocSize]byte)(unsafe.Pointer(n))
-	return (*[maxAllocSize]byte)(unsafe.Pointer(&buf[n.pos+n.ksize]))[:n.vsize:n.vsize]
-}
-
-// PageInfo represents human readable information about a page.
-type PageInfo struct {
-	ID            int
-	Type          string
-	Count         int
-	OverflowCount int
-}
-
-type pgids []pgid
-
-func (s pgids) Len() int           { return len(s) }
-func (s pgids) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
-func (s pgids) Less(i, j int) bool { return s[i] < s[j] }
-
-// merge returns the sorted union of a and b.
-func (a pgids) merge(b pgids) pgids {
-	// Return the opposite slice if one is nil.
-	if len(a) == 0 {
-		return b
-	}
-	if len(b) == 0 {
-		return a
-	}
-	merged := make(pgids, len(a)+len(b))
-	mergepgids(merged, a, b)
-	return merged
-}
-
-// mergepgids copies the sorted union of a and b into dst.
-// If dst is too small, it panics.
-func mergepgids(dst, a, b pgids) {
-	if len(dst) < len(a)+len(b) {
-		panic(fmt.Errorf("mergepgids bad len %d < %d + %d", len(dst), len(a), len(b)))
-	}
-	// Copy in the opposite slice if one is nil.
-	if len(a) == 0 {
-		copy(dst, b)
-		return
-	}
-	if len(b) == 0 {
-		copy(dst, a)
-		return
-	}
-
-	// Merged will hold all elements from both lists.
-	merged := dst[:0]
-
-	// Assign lead to the slice with a lower starting value, follow to the higher value.
-	lead, follow := a, b
-	if b[0] < a[0] {
-		lead, follow = b, a
-	}
-
-	// Continue while there are elements in the lead.
-	for len(lead) > 0 {
-		// Merge largest prefix of lead that is ahead of follow[0].
-		n := sort.Search(len(lead), func(i int) bool { return lead[i] > follow[0] })
-		merged = append(merged, lead[:n]...)
-		if n >= len(lead) {
-			break
-		}
-
-		// Swap lead and follow.
-		lead, follow = follow, lead[n:]
-	}
-
-	// Append what's left in follow.
-	_ = append(merged, follow...)
-}
diff --git a/vendor/github.com/etcd-io/bbolt/tx.go b/vendor/github.com/etcd-io/bbolt/tx.go
deleted file mode 100644
index 2df7688c2f..0000000000
--- a/vendor/github.com/etcd-io/bbolt/tx.go
+++ /dev/null
@@ -1,726 +0,0 @@
-package bbolt
-
-import (
-	"fmt"
-	"io"
-	"os"
-	"sort"
-	"strings"
-	"time"
-	"unsafe"
-)
-
-// txid represents the internal transaction identifier.
-type txid uint64
-
-// Tx represents a read-only or read/write transaction on the database.
-// Read-only transactions can be used for retrieving values for keys and creating cursors.
-// Read/write transactions can create and remove buckets and create and remove keys.
-//
-// IMPORTANT: You must commit or rollback transactions when you are done with
-// them. Pages can not be reclaimed by the writer until no more transactions
-// are using them. A long running read transaction can cause the database to
-// quickly grow.
-type Tx struct {
-	writable       bool
-	managed        bool
-	db             *DB
-	meta           *meta
-	root           Bucket
-	pages          map[pgid]*page
-	stats          TxStats
-	commitHandlers []func()
-
-	// WriteFlag specifies the flag for write-related methods like WriteTo().
-	// Tx opens the database file with the specified flag to copy the data.
-	//
-	// By default, the flag is unset, which works well for mostly in-memory
-	// workloads. For databases that are much larger than available RAM,
-	// set the flag to syscall.O_DIRECT to avoid trashing the page cache.
-	WriteFlag int
-}
-
-// init initializes the transaction.
-func (tx *Tx) init(db *DB) {
-	tx.db = db
-	tx.pages = nil
-
-	// Copy the meta page since it can be changed by the writer.
-	tx.meta = &meta{}
-	db.meta().copy(tx.meta)
-
-	// Copy over the root bucket.
-	tx.root = newBucket(tx)
-	tx.root.bucket = &bucket{}
-	*tx.root.bucket = tx.meta.root
-
-	// Increment the transaction id and add a page cache for writable transactions.
-	if tx.writable {
-		tx.pages = make(map[pgid]*page)
-		tx.meta.txid += txid(1)
-	}
-}
-
-// ID returns the transaction id.
-func (tx *Tx) ID() int {
-	return int(tx.meta.txid)
-}
-
-// DB returns a reference to the database that created the transaction.
-func (tx *Tx) DB() *DB {
-	return tx.db
-}
-
-// Size returns current database size in bytes as seen by this transaction.
-func (tx *Tx) Size() int64 {
-	return int64(tx.meta.pgid) * int64(tx.db.pageSize)
-}
-
-// Writable returns whether the transaction can perform write operations.
-func (tx *Tx) Writable() bool {
-	return tx.writable
-}
-
-// Cursor creates a cursor associated with the root bucket.
-// All items in the cursor will return a nil value because all root bucket keys point to buckets.
-// The cursor is only valid as long as the transaction is open.
-// Do not use a cursor after the transaction is closed.
-func (tx *Tx) Cursor() *Cursor {
-	return tx.root.Cursor()
-}
-
-// Stats retrieves a copy of the current transaction statistics.
-func (tx *Tx) Stats() TxStats {
-	return tx.stats
-}
-
-// Bucket retrieves a bucket by name.
-// Returns nil if the bucket does not exist.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (tx *Tx) Bucket(name []byte) *Bucket {
-	return tx.root.Bucket(name)
-}
-
-// CreateBucket creates a new bucket.
-// Returns an error if the bucket already exists, if the bucket name is blank, or if the bucket name is too long.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (tx *Tx) CreateBucket(name []byte) (*Bucket, error) {
-	return tx.root.CreateBucket(name)
-}
-
-// CreateBucketIfNotExists creates a new bucket if it doesn't already exist.
-// Returns an error if the bucket name is blank, or if the bucket name is too long.
-// The bucket instance is only valid for the lifetime of the transaction.
-func (tx *Tx) CreateBucketIfNotExists(name []byte) (*Bucket, error) {
-	return tx.root.CreateBucketIfNotExists(name)
-}
-
-// DeleteBucket deletes a bucket.
-// Returns an error if the bucket cannot be found or if the key represents a non-bucket value.
-func (tx *Tx) DeleteBucket(name []byte) error {
-	return tx.root.DeleteBucket(name)
-}
-
-// ForEach executes a function for each bucket in the root.
-// If the provided function returns an error then the iteration is stopped and
-// the error is returned to the caller.
-func (tx *Tx) ForEach(fn func(name []byte, b *Bucket) error) error {
-	return tx.root.ForEach(func(k, v []byte) error {
-		return fn(k, tx.root.Bucket(k))
-	})
-}
-
-// OnCommit adds a handler function to be executed after the transaction successfully commits.
-func (tx *Tx) OnCommit(fn func()) {
-	tx.commitHandlers = append(tx.commitHandlers, fn)
-}
-
-// Commit writes all changes to disk and updates the meta page.
-// Returns an error if a disk write error occurs, or if Commit is
-// called on a read-only transaction.
-func (tx *Tx) Commit() error {
-	_assert(!tx.managed, "managed tx commit not allowed")
-	if tx.db == nil {
-		return ErrTxClosed
-	} else if !tx.writable {
-		return ErrTxNotWritable
-	}
-
-	// TODO(benbjohnson): Use vectorized I/O to write out dirty pages.
-
-	// Rebalance nodes which have had deletions.
-	var startTime = time.Now()
-	tx.root.rebalance()
-	if tx.stats.Rebalance > 0 {
-		tx.stats.RebalanceTime += time.Since(startTime)
-	}
-
-	// spill data onto dirty pages.
-	startTime = time.Now()
-	if err := tx.root.spill(); err != nil {
-		tx.rollback()
-		return err
-	}
-	tx.stats.SpillTime += time.Since(startTime)
-
-	// Free the old root bucket.
-	tx.meta.root.root = tx.root.root
-
-	// Free the old freelist because commit writes out a fresh freelist.
-	if tx.meta.freelist != pgidNoFreelist {
-		tx.db.freelist.free(tx.meta.txid, tx.db.page(tx.meta.freelist))
-	}
-
-	if !tx.db.NoFreelistSync {
-		err := tx.commitFreelist()
-		if err != nil {
-			return err
-		}
-	} else {
-		tx.meta.freelist = pgidNoFreelist
-	}
-
-	// Write dirty pages to disk.
-	startTime = time.Now()
-	if err := tx.write(); err != nil {
-		tx.rollback()
-		return err
-	}
-
-	// If strict mode is enabled then perform a consistency check.
-	// Only the first consistency error is reported in the panic.
-	if tx.db.StrictMode {
-		ch := tx.Check()
-		var errs []string
-		for {
-			err, ok := <-ch
-			if !ok {
-				break
-			}
-			errs = append(errs, err.Error())
-		}
-		if len(errs) > 0 {
-			panic("check fail: " + strings.Join(errs, "\n"))
-		}
-	}
-
-	// Write meta to disk.
-	if err := tx.writeMeta(); err != nil {
-		tx.rollback()
-		return err
-	}
-	tx.stats.WriteTime += time.Since(startTime)
-
-	// Finalize the transaction.
-	tx.close()
-
-	// Execute commit handlers now that the locks have been removed.
-	for _, fn := range tx.commitHandlers {
-		fn()
-	}
-
-	return nil
-}
-
-func (tx *Tx) commitFreelist() error {
-	// Allocate new pages for the new free list. This will overestimate
-	// the size of the freelist but not underestimate the size (which would be bad).
-	opgid := tx.meta.pgid
-	p, err := tx.allocate((tx.db.freelist.size() / tx.db.pageSize) + 1)
-	if err != nil {
-		tx.rollback()
-		return err
-	}
-	if err := tx.db.freelist.write(p); err != nil {
-		tx.rollback()
-		return err
-	}
-	tx.meta.freelist = p.id
-	// If the high water mark has moved up then attempt to grow the database.
-	if tx.meta.pgid > opgid {
-		if err := tx.db.grow(int(tx.meta.pgid+1) * tx.db.pageSize); err != nil {
-			tx.rollback()
-			return err
-		}
-	}
-
-	return nil
-}
-
-// Rollback closes the transaction and ignores all previous updates. Read-only
-// transactions must be rolled back and not committed.
-func (tx *Tx) Rollback() error {
-	_assert(!tx.managed, "managed tx rollback not allowed")
-	if tx.db == nil {
-		return ErrTxClosed
-	}
-	tx.nonPhysicalRollback()
-	return nil
-}
-
-// nonPhysicalRollback is called when user calls Rollback directly, in this case we do not need to reload the free pages from disk.
-func (tx *Tx) nonPhysicalRollback() {
-	if tx.db == nil {
-		return
-	}
-	if tx.writable {
-		tx.db.freelist.rollback(tx.meta.txid)
-	}
-	tx.close()
-}
-
-// rollback needs to reload the free pages from disk in case some system error happens like fsync error.
-func (tx *Tx) rollback() {
-	if tx.db == nil {
-		return
-	}
-	if tx.writable {
-		tx.db.freelist.rollback(tx.meta.txid)
-		if !tx.db.hasSyncedFreelist() {
-			// Reconstruct free page list by scanning the DB to get the whole free page list.
-			// Note: scaning the whole db is heavy if your db size is large in NoSyncFreeList mode.
-			tx.db.freelist.noSyncReload(tx.db.freepages())
-		} else {
-			// Read free page list from freelist page.
-			tx.db.freelist.reload(tx.db.page(tx.db.meta().freelist))
-		}
-	}
-	tx.close()
-}
-
-func (tx *Tx) close() {
-	if tx.db == nil {
-		return
-	}
-	if tx.writable {
-		// Grab freelist stats.
-		var freelistFreeN = tx.db.freelist.free_count()
-		var freelistPendingN = tx.db.freelist.pending_count()
-		var freelistAlloc = tx.db.freelist.size()
-
-		// Remove transaction ref & writer lock.
-		tx.db.rwtx = nil
-		tx.db.rwlock.Unlock()
-
-		// Merge statistics.
-		tx.db.statlock.Lock()
-		tx.db.stats.FreePageN = freelistFreeN
-		tx.db.stats.PendingPageN = freelistPendingN
-		tx.db.stats.FreeAlloc = (freelistFreeN + freelistPendingN) * tx.db.pageSize
-		tx.db.stats.FreelistInuse = freelistAlloc
-		tx.db.stats.TxStats.add(&tx.stats)
-		tx.db.statlock.Unlock()
-	} else {
-		tx.db.removeTx(tx)
-	}
-
-	// Clear all references.
-	tx.db = nil
-	tx.meta = nil
-	tx.root = Bucket{tx: tx}
-	tx.pages = nil
-}
-
-// Copy writes the entire database to a writer.
-// This function exists for backwards compatibility.
-//
-// Deprecated; Use WriteTo() instead.
-func (tx *Tx) Copy(w io.Writer) error {
-	_, err := tx.WriteTo(w)
-	return err
-}
-
-// WriteTo writes the entire database to a writer.
-// If err == nil then exactly tx.Size() bytes will be written into the writer.
-func (tx *Tx) WriteTo(w io.Writer) (n int64, err error) {
-	// Attempt to open reader with WriteFlag
-	f, err := tx.db.openFile(tx.db.path, os.O_RDONLY|tx.WriteFlag, 0)
-	if err != nil {
-		return 0, err
-	}
-	defer func() {
-		if cerr := f.Close(); err == nil {
-			err = cerr
-		}
-	}()
-
-	// Generate a meta page. We use the same page data for both meta pages.
-	buf := make([]byte, tx.db.pageSize)
-	page := (*page)(unsafe.Pointer(&buf[0]))
-	page.flags = metaPageFlag
-	*page.meta() = *tx.meta
-
-	// Write meta 0.
-	page.id = 0
-	page.meta().checksum = page.meta().sum64()
-	nn, err := w.Write(buf)
-	n += int64(nn)
-	if err != nil {
-		return n, fmt.Errorf("meta 0 copy: %s", err)
-	}
-
-	// Write meta 1 with a lower transaction id.
-	page.id = 1
-	page.meta().txid -= 1
-	page.meta().checksum = page.meta().sum64()
-	nn, err = w.Write(buf)
-	n += int64(nn)
-	if err != nil {
-		return n, fmt.Errorf("meta 1 copy: %s", err)
-	}
-
-	// Move past the meta pages in the file.
-	if _, err := f.Seek(int64(tx.db.pageSize*2), io.SeekStart); err != nil {
-		return n, fmt.Errorf("seek: %s", err)
-	}
-
-	// Copy data pages.
-	wn, err := io.CopyN(w, f, tx.Size()-int64(tx.db.pageSize*2))
-	n += wn
-	if err != nil {
-		return n, err
-	}
-
-	return n, nil
-}
-
-// CopyFile copies the entire database to file at the given path.
-// A reader transaction is maintained during the copy so it is safe to continue
-// using the database while a copy is in progress.
-func (tx *Tx) CopyFile(path string, mode os.FileMode) error {
-	f, err := tx.db.openFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, mode)
-	if err != nil {
-		return err
-	}
-
-	err = tx.Copy(f)
-	if err != nil {
-		_ = f.Close()
-		return err
-	}
-	return f.Close()
-}
-
-// Check performs several consistency checks on the database for this transaction.
-// An error is returned if any inconsistency is found.
-//
-// It can be safely run concurrently on a writable transaction. However, this
-// incurs a high cost for large databases and databases with a lot of subbuckets
-// because of caching. This overhead can be removed if running on a read-only
-// transaction, however, it is not safe to execute other writer transactions at
-// the same time.
-func (tx *Tx) Check() <-chan error {
-	ch := make(chan error)
-	go tx.check(ch)
-	return ch
-}
-
-func (tx *Tx) check(ch chan error) {
-	// Force loading free list if opened in ReadOnly mode.
-	tx.db.loadFreelist()
-
-	// Check if any pages are double freed.
-	freed := make(map[pgid]bool)
-	all := make([]pgid, tx.db.freelist.count())
-	tx.db.freelist.copyall(all)
-	for _, id := range all {
-		if freed[id] {
-			ch <- fmt.Errorf("page %d: already freed", id)
-		}
-		freed[id] = true
-	}
-
-	// Track every reachable page.
-	reachable := make(map[pgid]*page)
-	reachable[0] = tx.page(0) // meta0
-	reachable[1] = tx.page(1) // meta1
-	if tx.meta.freelist != pgidNoFreelist {
-		for i := uint32(0); i <= tx.page(tx.meta.freelist).overflow; i++ {
-			reachable[tx.meta.freelist+pgid(i)] = tx.page(tx.meta.freelist)
-		}
-	}
-
-	// Recursively check buckets.
-	tx.checkBucket(&tx.root, reachable, freed, ch)
-
-	// Ensure all pages below high water mark are either reachable or freed.
-	for i := pgid(0); i < tx.meta.pgid; i++ {
-		_, isReachable := reachable[i]
-		if !isReachable && !freed[i] {
-			ch <- fmt.Errorf("page %d: unreachable unfreed", int(i))
-		}
-	}
-
-	// Close the channel to signal completion.
-	close(ch)
-}
-
-func (tx *Tx) checkBucket(b *Bucket, reachable map[pgid]*page, freed map[pgid]bool, ch chan error) {
-	// Ignore inline buckets.
-	if b.root == 0 {
-		return
-	}
-
-	// Check every page used by this bucket.
-	b.tx.forEachPage(b.root, 0, func(p *page, _ int) {
-		if p.id > tx.meta.pgid {
-			ch <- fmt.Errorf("page %d: out of bounds: %d", int(p.id), int(b.tx.meta.pgid))
-		}
-
-		// Ensure each page is only referenced once.
-		for i := pgid(0); i <= pgid(p.overflow); i++ {
-			var id = p.id + i
-			if _, ok := reachable[id]; ok {
-				ch <- fmt.Errorf("page %d: multiple references", int(id))
-			}
-			reachable[id] = p
-		}
-
-		// We should only encounter un-freed leaf and branch pages.
-		if freed[p.id] {
-			ch <- fmt.Errorf("page %d: reachable freed", int(p.id))
-		} else if (p.flags&branchPageFlag) == 0 && (p.flags&leafPageFlag) == 0 {
-			ch <- fmt.Errorf("page %d: invalid type: %s", int(p.id), p.typ())
-		}
-	})
-
-	// Check each bucket within this bucket.
-	_ = b.ForEach(func(k, v []byte) error {
-		if child := b.Bucket(k); child != nil {
-			tx.checkBucket(child, reachable, freed, ch)
-		}
-		return nil
-	})
-}
-
-// allocate returns a contiguous block of memory starting at a given page.
-func (tx *Tx) allocate(count int) (*page, error) {
-	p, err := tx.db.allocate(tx.meta.txid, count)
-	if err != nil {
-		return nil, err
-	}
-
-	// Save to our page cache.
-	tx.pages[p.id] = p
-
-	// Update statistics.
-	tx.stats.PageCount += count
-	tx.stats.PageAlloc += count * tx.db.pageSize
-
-	return p, nil
-}
-
-// write writes any dirty pages to disk.
-func (tx *Tx) write() error {
-	// Sort pages by id.
-	pages := make(pages, 0, len(tx.pages))
-	for _, p := range tx.pages {
-		pages = append(pages, p)
-	}
-	// Clear out page cache early.
-	tx.pages = make(map[pgid]*page)
-	sort.Sort(pages)
-
-	// Write pages to disk in order.
-	for _, p := range pages {
-		size := (int(p.overflow) + 1) * tx.db.pageSize
-		offset := int64(p.id) * int64(tx.db.pageSize)
-
-		// Write out page in "max allocation" sized chunks.
-		ptr := (*[maxAllocSize]byte)(unsafe.Pointer(p))
-		for {
-			// Limit our write to our max allocation size.
-			sz := size
-			if sz > maxAllocSize-1 {
-				sz = maxAllocSize - 1
-			}
-
-			// Write chunk to disk.
-			buf := ptr[:sz]
-			if _, err := tx.db.ops.writeAt(buf, offset); err != nil {
-				return err
-			}
-
-			// Update statistics.
-			tx.stats.Write++
-
-			// Exit inner for loop if we've written all the chunks.
-			size -= sz
-			if size == 0 {
-				break
-			}
-
-			// Otherwise move offset forward and move pointer to next chunk.
-			offset += int64(sz)
-			ptr = (*[maxAllocSize]byte)(unsafe.Pointer(&ptr[sz]))
-		}
-	}
-
-	// Ignore file sync if flag is set on DB.
-	if !tx.db.NoSync || IgnoreNoSync {
-		if err := fdatasync(tx.db); err != nil {
-			return err
-		}
-	}
-
-	// Put small pages back to page pool.
-	for _, p := range pages {
-		// Ignore page sizes over 1 page.
-		// These are allocated using make() instead of the page pool.
-		if int(p.overflow) != 0 {
-			continue
-		}
-
-		buf := (*[maxAllocSize]byte)(unsafe.Pointer(p))[:tx.db.pageSize]
-
-		// See https://go.googlesource.com/go/+/f03c9202c43e0abb130669852082117ca50aa9b1
-		for i := range buf {
-			buf[i] = 0
-		}
-		tx.db.pagePool.Put(buf)
-	}
-
-	return nil
-}
-
-// writeMeta writes the meta to the disk.
-func (tx *Tx) writeMeta() error {
-	// Create a temporary buffer for the meta page.
-	buf := make([]byte, tx.db.pageSize)
-	p := tx.db.pageInBuffer(buf, 0)
-	tx.meta.write(p)
-
-	// Write the meta page to file.
-	if _, err := tx.db.ops.writeAt(buf, int64(p.id)*int64(tx.db.pageSize)); err != nil {
-		return err
-	}
-	if !tx.db.NoSync || IgnoreNoSync {
-		if err := fdatasync(tx.db); err != nil {
-			return err
-		}
-	}
-
-	// Update statistics.
-	tx.stats.Write++
-
-	return nil
-}
-
-// page returns a reference to the page with a given id.
-// If page has been written to then a temporary buffered page is returned.
-func (tx *Tx) page(id pgid) *page {
-	// Check the dirty pages first.
-	if tx.pages != nil {
-		if p, ok := tx.pages[id]; ok {
-			return p
-		}
-	}
-
-	// Otherwise return directly from the mmap.
-	return tx.db.page(id)
-}
-
-// forEachPage iterates over every page within a given page and executes a function.
-func (tx *Tx) forEachPage(pgid pgid, depth int, fn func(*page, int)) {
-	p := tx.page(pgid)
-
-	// Execute function.
-	fn(p, depth)
-
-	// Recursively loop over children.
-	if (p.flags & branchPageFlag) != 0 {
-		for i := 0; i < int(p.count); i++ {
-			elem := p.branchPageElement(uint16(i))
-			tx.forEachPage(elem.pgid, depth+1, fn)
-		}
-	}
-}
-
-// Page returns page information for a given page number.
-// This is only safe for concurrent use when used by a writable transaction.
-func (tx *Tx) Page(id int) (*PageInfo, error) {
-	if tx.db == nil {
-		return nil, ErrTxClosed
-	} else if pgid(id) >= tx.meta.pgid {
-		return nil, nil
-	}
-
-	// Build the page info.
-	p := tx.db.page(pgid(id))
-	info := &PageInfo{
-		ID:            id,
-		Count:         int(p.count),
-		OverflowCount: int(p.overflow),
-	}
-
-	// Determine the type (or if it's free).
-	if tx.db.freelist.freed(pgid(id)) {
-		info.Type = "free"
-	} else {
-		info.Type = p.typ()
-	}
-
-	return info, nil
-}
-
-// TxStats represents statistics about the actions performed by the transaction.
-type TxStats struct {
-	// Page statistics.
-	PageCount int // number of page allocations
-	PageAlloc int // total bytes allocated
-
-	// Cursor statistics.
-	CursorCount int // number of cursors created
-
-	// Node statistics
-	NodeCount int // number of node allocations
-	NodeDeref int // number of node dereferences
-
-	// Rebalance statistics.
-	Rebalance     int           // number of node rebalances
-	RebalanceTime time.Duration // total time spent rebalancing
-
-	// Split/Spill statistics.
-	Split     int           // number of nodes split
-	Spill     int           // number of nodes spilled
-	SpillTime time.Duration // total time spent spilling
-
-	// Write statistics.
-	Write     int           // number of writes performed
-	WriteTime time.Duration // total time spent writing to disk
-}
-
-func (s *TxStats) add(other *TxStats) {
-	s.PageCount += other.PageCount
-	s.PageAlloc += other.PageAlloc
-	s.CursorCount += other.CursorCount
-	s.NodeCount += other.NodeCount
-	s.NodeDeref += other.NodeDeref
-	s.Rebalance += other.Rebalance
-	s.RebalanceTime += other.RebalanceTime
-	s.Split += other.Split
-	s.Spill += other.Spill
-	s.SpillTime += other.SpillTime
-	s.Write += other.Write
-	s.WriteTime += other.WriteTime
-}
-
-// Sub calculates and returns the difference between two sets of transaction stats.
-// This is useful when obtaining stats at two different points and time and
-// you need the performance counters that occurred within that time span.
-func (s *TxStats) Sub(other *TxStats) TxStats {
-	var diff TxStats
-	diff.PageCount = s.PageCount - other.PageCount
-	diff.PageAlloc = s.PageAlloc - other.PageAlloc
-	diff.CursorCount = s.CursorCount - other.CursorCount
-	diff.NodeCount = s.NodeCount - other.NodeCount
-	diff.NodeDeref = s.NodeDeref - other.NodeDeref
-	diff.Rebalance = s.Rebalance - other.Rebalance
-	diff.RebalanceTime = s.RebalanceTime - other.RebalanceTime
-	diff.Split = s.Split - other.Split
-	diff.Spill = s.Spill - other.Spill
-	diff.SpillTime = s.SpillTime - other.SpillTime
-	diff.Write = s.Write - other.Write
-	diff.WriteTime = s.WriteTime - other.WriteTime
-	return diff
-}
diff --git a/vendor/github.com/golang/protobuf/proto/buffer.go b/vendor/github.com/golang/protobuf/proto/buffer.go
index 62df7e3b8b..e810e6fea1 100644
--- a/vendor/github.com/golang/protobuf/proto/buffer.go
+++ b/vendor/github.com/golang/protobuf/proto/buffer.go
@@ -33,8 +33,8 @@ func SizeVarint(v uint64) int {
 	return protowire.SizeVarint(v)
 }
 
-// DecodeVarint parses a varint encoded integer from b, returning the
-// integer value and the length of the varint.
+// DecodeVarint parses a varint encoded integer from b,
+// returning the integer value and the length of the varint.
 // It returns (0, 0) if there is a parse error.
 func DecodeVarint(b []byte) (uint64, int) {
 	v, n := protowire.ConsumeVarint(b)
@@ -112,9 +112,9 @@ func (b *Buffer) Marshal(m Message) error {
 	return err
 }
 
-// Unmarshal parses the wire-format message in the buffer and places the decoded results in m.
-//
-// Unlike proto.Unmarshal, this does not reset the message before starting to unmarshal.
+// Unmarshal parses the wire-format message in the buffer and
+// places the decoded results in m.
+// It does not reset m before unmarshaling.
 func (b *Buffer) Unmarshal(m Message) error {
 	err := UnmarshalMerge(b.Unread(), m)
 	b.idx = len(b.buf)
@@ -260,7 +260,7 @@ func (b *Buffer) DecodeStringBytes() (string, error) {
 }
 
 // DecodeMessage consumes a length-prefixed message from the buffer.
-// It does not reset m.
+// It does not reset m before unmarshaling.
 func (b *Buffer) DecodeMessage(m Message) error {
 	v, err := b.DecodeRawBytes(false)
 	if err != nil {
@@ -272,7 +272,7 @@ func (b *Buffer) DecodeMessage(m Message) error {
 // DecodeGroup consumes a message group from the buffer.
 // It assumes that the start group marker has already been consumed and
 // consumes all bytes until (and including the end group marker).
-// It does not reset m.
+// It does not reset m before unmarshaling.
 func (b *Buffer) DecodeGroup(m Message) error {
 	v, n, err := consumeGroup(b.buf[b.idx:])
 	if err != nil {
diff --git a/vendor/github.com/golang/protobuf/proto/extensions.go b/vendor/github.com/golang/protobuf/proto/extensions.go
index 5ed131c57d..42fc120c97 100644
--- a/vendor/github.com/golang/protobuf/proto/extensions.go
+++ b/vendor/github.com/golang/protobuf/proto/extensions.go
@@ -68,7 +68,7 @@ func HasExtension(m Message, xt *ExtensionDesc) (has bool) {
 	return has
 }
 
-// ClearExtension removes the the exntesion field from m
+// ClearExtension removes the extension field from m
 // either as an explicitly populated field or as an unknown field.
 func ClearExtension(m Message, xt *ExtensionDesc) {
 	mr := MessageReflect(m)
@@ -108,7 +108,7 @@ func ClearAllExtensions(m Message) {
 	clearUnknown(mr, mr.Descriptor().ExtensionRanges())
 }
 
-// GetExtension retrieves a proto2 extended field from pb.
+// GetExtension retrieves a proto2 extended field from m.
 //
 // If the descriptor is type complete (i.e., ExtensionDesc.ExtensionType is non-nil),
 // then GetExtension parses the encoded field and returns a Go value of the specified type.
diff --git a/vendor/github.com/golang/protobuf/proto/registry.go b/vendor/github.com/golang/protobuf/proto/registry.go
index abab110a06..1e7ff64205 100644
--- a/vendor/github.com/golang/protobuf/proto/registry.go
+++ b/vendor/github.com/golang/protobuf/proto/registry.go
@@ -29,7 +29,7 @@ var fileCache sync.Map // map[filePath]fileDescGZIP
 // RegisterFile is called from generated code to register the compressed
 // FileDescriptorProto with the file path for a proto source file.
 //
-// Deprecated: Use protoregistry.GlobalFiles.Register instead.
+// Deprecated: Use protoregistry.GlobalFiles.RegisterFile instead.
 func RegisterFile(s filePath, d fileDescGZIP) {
 	// Decompress the descriptor.
 	zr, err := gzip.NewReader(bytes.NewReader(d))
@@ -53,7 +53,7 @@ func RegisterFile(s filePath, d fileDescGZIP) {
 // FileDescriptor returns the compressed FileDescriptorProto given the file path
 // for a proto source file. It returns nil if not found.
 //
-// Deprecated: Use protoregistry.GlobalFiles.RangeFilesByPath instead.
+// Deprecated: Use protoregistry.GlobalFiles.FindFileByPath instead.
 func FileDescriptor(s filePath) fileDescGZIP {
 	if v, ok := fileCache.Load(s); ok {
 		return v.(fileDescGZIP)
@@ -98,7 +98,7 @@ var numFilesCache sync.Map // map[protoreflect.FullName]int
 // RegisterEnum is called from the generated code to register the mapping of
 // enum value names to enum numbers for the enum identified by s.
 //
-// Deprecated: Use protoregistry.GlobalTypes.Register instead.
+// Deprecated: Use protoregistry.GlobalTypes.RegisterEnum instead.
 func RegisterEnum(s enumName, _ enumsByNumber, m enumsByName) {
 	if _, ok := enumCache.Load(s); ok {
 		panic("proto: duplicate enum registered: " + s)
@@ -181,7 +181,7 @@ var messageTypeCache sync.Map // map[messageName]reflect.Type
 // RegisterType is called from generated code to register the message Go type
 // for a message of the given name.
 //
-// Deprecated: Use protoregistry.GlobalTypes.Register instead.
+// Deprecated: Use protoregistry.GlobalTypes.RegisterMessage instead.
 func RegisterType(m Message, s messageName) {
 	mt := protoimpl.X.LegacyMessageTypeOf(m, protoreflect.FullName(s))
 	if err := protoregistry.GlobalTypes.RegisterMessage(mt); err != nil {
@@ -280,7 +280,7 @@ func MessageName(m Message) messageName {
 // RegisterExtension is called from the generated code to register
 // the extension descriptor.
 //
-// Deprecated: Use protoregistry.GlobalTypes.Register instead.
+// Deprecated: Use protoregistry.GlobalTypes.RegisterExtension instead.
 func RegisterExtension(d *ExtensionDesc) {
 	if err := protoregistry.GlobalTypes.RegisterExtension(d); err != nil {
 		panic(err)
diff --git a/vendor/github.com/golang/protobuf/proto/text_encode.go b/vendor/github.com/golang/protobuf/proto/text_encode.go
index 7ac02e68f6..a31134eeb3 100644
--- a/vendor/github.com/golang/protobuf/proto/text_encode.go
+++ b/vendor/github.com/golang/protobuf/proto/text_encode.go
@@ -94,16 +94,16 @@ var (
 )
 
 // MarshalText writes the proto text format of m to w.
-func MarshalText(w io.Writer, pb Message) error { return defaultTextMarshaler.Marshal(w, pb) }
+func MarshalText(w io.Writer, m Message) error { return defaultTextMarshaler.Marshal(w, m) }
 
 // MarshalTextString returns a proto text formatted string of m.
-func MarshalTextString(pb Message) string { return defaultTextMarshaler.Text(pb) }
+func MarshalTextString(m Message) string { return defaultTextMarshaler.Text(m) }
 
 // CompactText writes the compact proto text format of m to w.
-func CompactText(w io.Writer, pb Message) error { return compactTextMarshaler.Marshal(w, pb) }
+func CompactText(w io.Writer, m Message) error { return compactTextMarshaler.Marshal(w, m) }
 
 // CompactTextString returns a compact proto text formatted string of m.
-func CompactTextString(pb Message) string { return compactTextMarshaler.Text(pb) }
+func CompactTextString(m Message) string { return compactTextMarshaler.Text(m) }
 
 var (
 	newline         = []byte("\n")
diff --git a/vendor/github.com/mschoch/smat/go.mod b/vendor/github.com/mschoch/smat/go.mod
new file mode 100644
index 0000000000..70c9eed57e
--- /dev/null
+++ b/vendor/github.com/mschoch/smat/go.mod
@@ -0,0 +1,3 @@
+module github.com/mschoch/smat
+
+go 1.13
diff --git a/vendor/github.com/steveyen/gtreap/go.mod b/vendor/github.com/steveyen/gtreap/go.mod
new file mode 100644
index 0000000000..328430b210
--- /dev/null
+++ b/vendor/github.com/steveyen/gtreap/go.mod
@@ -0,0 +1,3 @@
+module github.com/steveyen/gtreap
+
+go 1.13
diff --git a/vendor/github.com/tinylib/msgp/msgp/json.go b/vendor/github.com/tinylib/msgp/msgp/json.go
index 4325860ada..77601e52c3 100644
--- a/vendor/github.com/tinylib/msgp/msgp/json.go
+++ b/vendor/github.com/tinylib/msgp/msgp/json.go
@@ -466,7 +466,23 @@ func rwquoted(dst jsWriter, s []byte) (n int, err error) {
 					return
 				}
 				n++
+			case '\t':
+				err = dst.WriteByte('\\')
+				if err != nil {
+					return
+				}
+				n++
+				err = dst.WriteByte('t')
+				if err != nil {
+					return
+				}
+				n++
 			default:
+				// This encodes bytes < 0x20 except for \t, \n and \r.
+				// It also escapes <, >, and &
+				// because they can lead to security holes when
+				// user-controlled strings are rendered into JSON
+				// and served to some browsers.
 				nn, err = dst.WriteString(`\u00`)
 				n += nn
 				if err != nil {
@@ -495,16 +511,23 @@ func rwquoted(dst jsWriter, s []byte) (n int, err error) {
 				if err != nil {
 					return
 				}
-				nn, err = dst.WriteString(`\ufffd`)
-				n += nn
-				if err != nil {
-					return
-				}
-				i += size
-				start = i
-				continue
 			}
+			nn, err = dst.WriteString(`\ufffd`)
+			n += nn
+			if err != nil {
+				return
+			}
+			i += size
+			start = i
+			continue
 		}
+		// U+2028 is LINE SEPARATOR.
+		// U+2029 is PARAGRAPH SEPARATOR.
+		// They are both technically valid characters in JSON strings,
+		// but don't work in JSONP, which has to be evaluated as JavaScript,
+		// and can lead to security holes there. It is valid JSON to
+		// escape them, so we do so unconditionally.
+		// See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
 		if c == '\u2028' || c == '\u2029' {
 			if start < i {
 				nn, err = dst.Write(s[start:i])
@@ -512,17 +535,20 @@ func rwquoted(dst jsWriter, s []byte) (n int, err error) {
 				if err != nil {
 					return
 				}
-				nn, err = dst.WriteString(`\u202`)
-				n += nn
-				if err != nil {
-					return
-				}
-				err = dst.WriteByte(hex[c&0xF])
-				if err != nil {
-					return
-				}
-				n++
 			}
+			nn, err = dst.WriteString(`\u202`)
+			n += nn
+			if err != nil {
+				return
+			}
+			err = dst.WriteByte(hex[c&0xF])
+			if err != nil {
+				return
+			}
+			n++
+			i += size
+			start = i
+			continue
 		}
 		i += size
 	}