10 files changed, 591 insertions, 0 deletions

diff --git a/modules/indexer/internal/base32.go b/modules/indexer/internal/base32.go
new file mode 100644
index 0000000000..aca756c638
--- /dev/null
+++ b/modules/indexer/internal/base32.go
@@ -0,0 +1,21 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package internal
+
+import (
+	"fmt"
+	"strconv"
+)
+
+func Base36(i int64) string {
+	return strconv.FormatInt(i, 36)
+}
+
+func ParseBase36(s string) (int64, error) {
+	i, err := strconv.ParseInt(s, 36, 64)
+	if err != nil {
+		return 0, fmt.Errorf("invalid base36 integer %q: %w", s, err)
+	}
+	return i, nil
+}
diff --git a/modules/indexer/internal/bleve/batch.go b/modules/indexer/internal/bleve/batch.go
new file mode 100644
index 0000000000..77675147b2
--- /dev/null
+++ b/modules/indexer/internal/bleve/batch.go
@@ -0,0 +1,58 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package bleve
+
+import (
+	"github.com/blevesearch/bleve/v2"
+)
+
+// FlushingBatch is a batch of operations that automatically flushes to the
+// underlying index once it reaches a certain size.
+type FlushingBatch struct {
+	maxBatchSize int
+	batch        *bleve.Batch
+	index        bleve.Index
+}
+
+// NewFlushingBatch creates a new flushing batch for the specified index. Once
+// the number of operations in the batch reaches the specified limit, the batch
+// automatically flushes its operations to the index.
+func NewFlushingBatch(index bleve.Index, maxBatchSize int) *FlushingBatch {
+	return &FlushingBatch{
+		maxBatchSize: maxBatchSize,
+		batch:        index.NewBatch(),
+		index:        index,
+	}
+}
+
+// Index add a new index to batch
+func (b *FlushingBatch) Index(id string, data interface{}) error {
+	if err := b.batch.Index(id, data); err != nil {
+		return err
+	}
+	return b.flushIfFull()
+}
+
+// Delete add a delete index to batch
+func (b *FlushingBatch) Delete(id string) error {
+	b.batch.Delete(id)
+	return b.flushIfFull()
+}
+
+func (b *FlushingBatch) flushIfFull() error {
+	if b.batch.Size() < b.maxBatchSize {
+		return nil
+	}
+	return b.Flush()
+}
+
+// Flush submit the batch and create a new one
+func (b *FlushingBatch) Flush() error {
+	err := b.index.Batch(b.batch)
+	if err != nil {
+		return err
+	}
+	b.batch = b.index.NewBatch()
+	return nil
+}
diff --git a/modules/indexer/internal/bleve/indexer.go b/modules/indexer/internal/bleve/indexer.go
new file mode 100644
index 0000000000..ce06b5afcb
--- /dev/null
+++ b/modules/indexer/internal/bleve/indexer.go
@@ -0,0 +1,103 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package bleve
+
+import (
+	"context"
+	"fmt"
+
+	"code.gitea.io/gitea/modules/indexer/internal"
+	"code.gitea.io/gitea/modules/log"
+
+	"github.com/blevesearch/bleve/v2"
+	"github.com/blevesearch/bleve/v2/mapping"
+	"github.com/ethantkoenig/rupture"
+)
+
+var _ internal.Indexer = &Indexer{}
+
+// Indexer represents a basic bleve indexer implementation
+type Indexer struct {
+	Indexer bleve.Index
+
+	indexDir      string
+	version       int
+	mappingGetter MappingGetter
+}
+
+type MappingGetter func() (mapping.IndexMapping, error)
+
+func NewIndexer(indexDir string, version int, mappingGetter func() (mapping.IndexMapping, error)) *Indexer {
+	return &Indexer{
+		indexDir:      indexDir,
+		version:       version,
+		mappingGetter: mappingGetter,
+	}
+}
+
+// Init initializes the indexer
+func (i *Indexer) Init(_ context.Context) (bool, error) {
+	if i == nil {
+		return false, fmt.Errorf("cannot init nil indexer")
+	}
+
+	if i.Indexer != nil {
+		return false, fmt.Errorf("indexer is already initialized")
+	}
+
+	indexer, version, err := openIndexer(i.indexDir, i.version)
+	if err != nil {
+		return false, err
+	}
+	if indexer != nil {
+		i.Indexer = indexer
+		return true, nil
+	}
+
+	if version != 0 {
+		log.Warn("Found older bleve index with version %d, Gitea will remove it and rebuild", version)
+	}
+
+	indexMapping, err := i.mappingGetter()
+	if err != nil {
+		return false, err
+	}
+
+	indexer, err = bleve.New(i.indexDir, indexMapping)
+	if err != nil {
+		return false, err
+	}
+
+	if err = rupture.WriteIndexMetadata(i.indexDir, &rupture.IndexMetadata{
+		Version: i.version,
+	}); err != nil {
+		return false, err
+	}
+
+	i.Indexer = indexer
+
+	return false, nil
+}
+
+// Ping checks if the indexer is available
+func (i *Indexer) Ping(_ context.Context) error {
+	if i == nil {
+		return fmt.Errorf("cannot ping nil indexer")
+	}
+	if i.Indexer == nil {
+		return fmt.Errorf("indexer is not initialized")
+	}
+	return nil
+}
+
+func (i *Indexer) Close() {
+	if i == nil {
+		return
+	}
+
+	if err := i.Indexer.Close(); err != nil {
+		log.Error("Failed to close bleve indexer in %q: %v", i.indexDir, err)
+	}
+	i.Indexer = nil
+}
diff --git a/modules/indexer/internal/bleve/util.go b/modules/indexer/internal/bleve/util.go
new file mode 100644
index 0000000000..43a7c3c5ec
--- /dev/null
+++ b/modules/indexer/internal/bleve/util.go
@@ -0,0 +1,49 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package bleve
+
+import (
+	"errors"
+	"os"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/util"
+
+	"github.com/blevesearch/bleve/v2"
+	"github.com/blevesearch/bleve/v2/index/upsidedown"
+	"github.com/ethantkoenig/rupture"
+)
+
+// openIndexer open the index at the specified path, checking for metadata
+// updates and bleve version updates.  If index needs to be created (or
+// re-created), returns (nil, nil)
+func openIndexer(path string, latestVersion int) (bleve.Index, int, error) {
+	_, err := os.Stat(path)
+	if err != nil && os.IsNotExist(err) {
+		return nil, 0, nil
+	} else if err != nil {
+		return nil, 0, err
+	}
+
+	metadata, err := rupture.ReadIndexMetadata(path)
+	if err != nil {
+		return nil, 0, err
+	}
+	if metadata.Version < latestVersion {
+		// the indexer is using a previous version, so we should delete it and
+		// re-populate
+		return nil, metadata.Version, util.RemoveAll(path)
+	}
+
+	index, err := bleve.Open(path)
+	if err != nil {
+		if errors.Is(err, upsidedown.IncompatibleVersion) {
+			log.Warn("Indexer was built with a previous version of bleve, deleting and rebuilding")
+			return nil, 0, util.RemoveAll(path)
+		}
+		return nil, 0, err
+	}
+
+	return index, 0, nil
+}
diff --git a/modules/indexer/internal/db/indexer.go b/modules/indexer/internal/db/indexer.go
new file mode 100644
index 0000000000..3f7e00efbb
--- /dev/null
+++ b/modules/indexer/internal/db/indexer.go
@@ -0,0 +1,33 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db
+
+import (
+	"context"
+
+	"code.gitea.io/gitea/modules/indexer/internal"
+)
+
+var _ internal.Indexer = &Indexer{}
+
+// Indexer represents a basic db indexer implementation
+type Indexer struct{}
+
+// Init initializes the indexer
+func (i *Indexer) Init(_ context.Context) (bool, error) {
+	// nothing to do
+	return false, nil
+}
+
+// Ping checks if the indexer is available
+func (i *Indexer) Ping(_ context.Context) error {
+	// No need to ping database to check if it is available.
+	// If the database goes down, Gitea will go down, so nobody will care if the indexer is available.
+	return nil
+}
+
+// Close closes the indexer
+func (i *Indexer) Close() {
+	// nothing to do
+}
diff --git a/modules/indexer/internal/elasticsearch/indexer.go b/modules/indexer/internal/elasticsearch/indexer.go
new file mode 100644
index 0000000000..2c60efad56
--- /dev/null
+++ b/modules/indexer/internal/elasticsearch/indexer.go
@@ -0,0 +1,92 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package elasticsearch
+
+import (
+	"context"
+	"fmt"
+
+	"code.gitea.io/gitea/modules/indexer/internal"
+
+	"github.com/olivere/elastic/v7"
+)
+
+var _ internal.Indexer = &Indexer{}
+
+// Indexer represents a basic elasticsearch indexer implementation
+type Indexer struct {
+	Client *elastic.Client
+
+	url       string
+	indexName string
+	version   int
+	mapping   string
+}
+
+func NewIndexer(url, indexName string, version int, mapping string) *Indexer {
+	return &Indexer{
+		url:       url,
+		indexName: indexName,
+		version:   version,
+		mapping:   mapping,
+	}
+}
+
+// Init initializes the indexer
+func (i *Indexer) Init(ctx context.Context) (bool, error) {
+	if i == nil {
+		return false, fmt.Errorf("cannot init nil indexer")
+	}
+	if i.Client != nil {
+		return false, fmt.Errorf("indexer is already initialized")
+	}
+
+	client, err := i.initClient()
+	if err != nil {
+		return false, err
+	}
+	i.Client = client
+
+	exists, err := i.Client.IndexExists(i.VersionedIndexName()).Do(ctx)
+	if err != nil {
+		return false, err
+	}
+	if exists {
+		return true, nil
+	}
+
+	if err := i.createIndex(ctx); err != nil {
+		return false, err
+	}
+
+	return exists, nil
+}
+
+// Ping checks if the indexer is available
+func (i *Indexer) Ping(ctx context.Context) error {
+	if i == nil {
+		return fmt.Errorf("cannot ping nil indexer")
+	}
+	if i.Client == nil {
+		return fmt.Errorf("indexer is not initialized")
+	}
+
+	resp, err := i.Client.ClusterHealth().Do(ctx)
+	if err != nil {
+		return err
+	}
+	if resp.Status != "green" {
+		// see https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-health.html
+		return fmt.Errorf("status of elasticsearch cluster is %s", resp.Status)
+	}
+	return nil
+}
+
+// Close closes the indexer
+func (i *Indexer) Close() {
+	if i == nil {
+		return
+	}
+	i.Client = nil
+}
diff --git a/modules/indexer/internal/elasticsearch/util.go b/modules/indexer/internal/elasticsearch/util.go
new file mode 100644
index 0000000000..9e034bd553
--- /dev/null
+++ b/modules/indexer/internal/elasticsearch/util.go
@@ -0,0 +1,68 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package elasticsearch
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+
+	"github.com/olivere/elastic/v7"
+)
+
+// VersionedIndexName returns the full index name with version
+func (i *Indexer) VersionedIndexName() string {
+	return versionedIndexName(i.indexName, i.version)
+}
+
+func versionedIndexName(indexName string, version int) string {
+	if version == 0 {
+		// Old index name without version
+		return indexName
+	}
+	return fmt.Sprintf("%s.v%d", indexName, version)
+}
+
+func (i *Indexer) createIndex(ctx context.Context) error {
+	createIndex, err := i.Client.CreateIndex(i.VersionedIndexName()).BodyString(i.mapping).Do(ctx)
+	if err != nil {
+		return err
+	}
+	if !createIndex.Acknowledged {
+		return fmt.Errorf("create index %s with %s failed", i.VersionedIndexName(), i.mapping)
+	}
+
+	i.checkOldIndexes(ctx)
+
+	return nil
+}
+
+func (i *Indexer) initClient() (*elastic.Client, error) {
+	opts := []elastic.ClientOptionFunc{
+		elastic.SetURL(i.url),
+		elastic.SetSniff(false),
+		elastic.SetHealthcheckInterval(10 * time.Second),
+		elastic.SetGzip(false),
+	}
+
+	logger := log.GetLogger(log.DEFAULT)
+
+	opts = append(opts, elastic.SetTraceLog(&log.PrintfLogger{Logf: logger.Trace}))
+	opts = append(opts, elastic.SetInfoLog(&log.PrintfLogger{Logf: logger.Info}))
+	opts = append(opts, elastic.SetErrorLog(&log.PrintfLogger{Logf: logger.Error}))
+
+	return elastic.NewClient(opts...)
+}
+
+func (i *Indexer) checkOldIndexes(ctx context.Context) {
+	for v := 0; v < i.version; v++ {
+		indexName := versionedIndexName(i.indexName, v)
+		exists, err := i.Client.IndexExists(indexName).Do(ctx)
+		if err == nil && exists {
+			log.Warn("Found older elasticsearch index named %q, Gitea will keep the old NOT DELETED. You can delete the old version after the upgrade succeed.", indexName)
+		}
+	}
+}
diff --git a/modules/indexer/internal/indexer.go b/modules/indexer/internal/indexer.go
new file mode 100644
index 0000000000..c7f356da1e
--- /dev/null
+++ b/modules/indexer/internal/indexer.go
@@ -0,0 +1,37 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package internal
+
+import (
+	"context"
+	"fmt"
+)
+
+// Indexer defines an basic indexer interface
+type Indexer interface {
+	// Init initializes the indexer
+	// returns true if the index was opened/existed (with data populated), false if it was created/not-existed (with no data)
+	Init(ctx context.Context) (bool, error)
+	// Ping checks if the indexer is available
+	Ping(ctx context.Context) error
+	// Close closes the indexer
+	Close()
+}
+
+// NewDummyIndexer returns a dummy indexer
+func NewDummyIndexer() Indexer {
+	return &dummyIndexer{}
+}
+
+type dummyIndexer struct{}
+
+func (d *dummyIndexer) Init(ctx context.Context) (bool, error) {
+	return false, fmt.Errorf("indexer is not ready")
+}
+
+func (d *dummyIndexer) Ping(ctx context.Context) error {
+	return fmt.Errorf("indexer is not ready")
+}
+
+func (d *dummyIndexer) Close() {}
diff --git a/modules/indexer/internal/meilisearch/indexer.go b/modules/indexer/internal/meilisearch/indexer.go
new file mode 100644
index 0000000000..06747ff7e0
--- /dev/null
+++ b/modules/indexer/internal/meilisearch/indexer.go
@@ -0,0 +1,92 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package meilisearch
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/meilisearch/meilisearch-go"
+)
+
+// Indexer represents a basic meilisearch indexer implementation
+type Indexer struct {
+	Client *meilisearch.Client
+
+	url, apiKey string
+	indexName   string
+	version     int
+}
+
+func NewIndexer(url, apiKey, indexName string, version int) *Indexer {
+	return &Indexer{
+		url:       url,
+		apiKey:    apiKey,
+		indexName: indexName,
+		version:   version,
+	}
+}
+
+// Init initializes the indexer
+func (i *Indexer) Init(_ context.Context) (bool, error) {
+	if i == nil {
+		return false, fmt.Errorf("cannot init nil indexer")
+	}
+
+	if i.Client != nil {
+		return false, fmt.Errorf("indexer is already initialized")
+	}
+
+	i.Client = meilisearch.NewClient(meilisearch.ClientConfig{
+		Host:   i.url,
+		APIKey: i.apiKey,
+	})
+
+	_, err := i.Client.GetIndex(i.VersionedIndexName())
+	if err == nil {
+		return true, nil
+	}
+	_, err = i.Client.CreateIndex(&meilisearch.IndexConfig{
+		Uid:        i.VersionedIndexName(),
+		PrimaryKey: "id",
+	})
+	if err != nil {
+		return false, err
+	}
+
+	i.checkOldIndexes()
+
+	_, err = i.Client.Index(i.VersionedIndexName()).UpdateFilterableAttributes(&[]string{"repo_id"})
+	return false, err
+}
+
+// Ping checks if the indexer is available
+func (i *Indexer) Ping(ctx context.Context) error {
+	if i == nil {
+		return fmt.Errorf("cannot ping nil indexer")
+	}
+	if i.Client == nil {
+		return fmt.Errorf("indexer is not initialized")
+	}
+	resp, err := i.Client.Health()
+	if err != nil {
+		return err
+	}
+	if resp.Status != "available" {
+		// See https://docs.meilisearch.com/reference/api/health.html#status
+		return fmt.Errorf("status of meilisearch is not available: %s", resp.Status)
+	}
+	return nil
+}
+
+// Close closes the indexer
+func (i *Indexer) Close() {
+	if i == nil {
+		return
+	}
+	if i.Client == nil {
+		return
+	}
+	i.Client = nil
+}
diff --git a/modules/indexer/internal/meilisearch/util.go b/modules/indexer/internal/meilisearch/util.go
new file mode 100644
index 0000000000..e6d8fefade
--- /dev/null
+++ b/modules/indexer/internal/meilisearch/util.go
@@ -0,0 +1,38 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package meilisearch
+
+import (
+	"fmt"
+
+	"code.gitea.io/gitea/modules/log"
+)
+
+// VersionedIndexName returns the full index name with version
+func (i *Indexer) VersionedIndexName() string {
+	return versionedIndexName(i.indexName, i.version)
+}
+
+func versionedIndexName(indexName string, version int) string {
+	if version == 0 {
+		// Old index name without version
+		return indexName
+	}
+
+	// The format of the index name is <index_name>_v<version>, not <index_name>.v<version> like elasticsearch.
+	// Because meilisearch does not support "." in index name, it should contain only alphanumeric characters, hyphens (-) and underscores (_).
+	// See https://www.meilisearch.com/docs/learn/core_concepts/indexes#index-uid
+
+	return fmt.Sprintf("%s_v%d", indexName, version)
+}
+
+func (i *Indexer) checkOldIndexes() {
+	for v := 0; v < i.version; v++ {
+		indexName := versionedIndexName(i.indexName, v)
+		_, err := i.Client.GetIndex(indexName)
+		if err == nil {
+			log.Warn("Found older meilisearch index named %q, Gitea will keep the old NOT DELETED. You can delete the old version after the upgrade succeed.", indexName)
+		}
+	}
+}