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-rw-r--r--vendor/github.com/ethantkoenig/rupture/metadata.go68
1 files changed, 68 insertions, 0 deletions
diff --git a/vendor/github.com/ethantkoenig/rupture/metadata.go b/vendor/github.com/ethantkoenig/rupture/metadata.go
new file mode 100644
index 0000000000..f26b53d96b
--- /dev/null
+++ b/vendor/github.com/ethantkoenig/rupture/metadata.go
@@ -0,0 +1,68 @@
+package rupture
+
+import (
+ "encoding/json"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+)
+
+const metaFilename = "rupture_meta.json"
+
+func indexMetadataPath(dir string) string {
+ return filepath.Join(dir, metaFilename)
+}
+
+// IndexMetadata contains metadata about a bleve index.
+type IndexMetadata struct {
+ // The version of the data in the index. This can be useful for tracking
+ // schema changes or data migrations.
+ Version int `json:"version"`
+}
+
+// in addition to the user-exposed metadata, we keep additional, internal-only
+// metadata for sharded indices.
+const shardedMetadataFilename = "rupture_sharded_meta.json"
+
+func shardedIndexMetadataPath(dir string) string {
+ return filepath.Join(dir, shardedMetadataFilename)
+}
+
+type shardedIndexMetadata struct {
+ NumShards int `json:"num_shards"`
+}
+
+func readJSON(path string, meta interface{}) error {
+ metaBytes, err := ioutil.ReadFile(path)
+ if err != nil {
+ return err
+ }
+ return json.Unmarshal(metaBytes, meta)
+}
+
+func writeJSON(path string, meta interface{}) error {
+ metaBytes, err := json.Marshal(meta)
+ if err != nil {
+ return err
+ }
+ return ioutil.WriteFile(path, metaBytes, 0666)
+}
+
+// ReadIndexMetadata returns the metadata for the index at the specified path.
+// If no such index metadata exists, an empty metadata and a nil error are
+// returned.
+func ReadIndexMetadata(path string) (*IndexMetadata, error) {
+ meta := &IndexMetadata{}
+ metaPath := indexMetadataPath(path)
+ if _, err := os.Stat(metaPath); os.IsNotExist(err) {
+ return meta, nil
+ } else if err != nil {
+ return nil, err
+ }
+ return meta, readJSON(metaPath, meta)
+}
+
+// WriteIndexMetadata writes metadata for the index at the specified path.
+func WriteIndexMetadata(path string, meta *IndexMetadata) error {
+ return writeJSON(indexMetadataPath(path), meta)
+}