gitea/modules/indexer/internal/bleve/util.go

62 lines
1.7 KiB
Go

// 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
}
func GuessFuzzinessByKeyword(s string) int {
// according to https://github.com/blevesearch/bleve/issues/1563, the supported max fuzziness is 2
// magic number 4 was chosen to determine the levenshtein distance per each character of a keyword
// BUT, when using CJK (eg: `갃갃갃` `啊啊啊`), it mismatches a lot.
for _, r := range s {
if r >= 128 {
return 0
}
}
return min(2, len(s)/4)
}