69 lines
1.7 KiB
Go
69 lines
1.7 KiB
Go
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)
|
|
}
|