forgejo/modules/indexer/issues/bleve/bleve.go
Jason Song 375fd15fbf
Refactor indexer (#25174)
Refactor `modules/indexer` to make it more maintainable. And it can be
easier to support more features. I'm trying to solve some of issue
searching, this is a precursor to making functional changes.

Current supported engines and the index versions:

| engines | issues | code |
| - | - | - |
| db | Just a wrapper for database queries, doesn't need version | - |
| bleve | The version of index is **2** | The version of index is **6**
|
| elasticsearch | The old index has no version, will be treated as
version **0** in this PR | The version of index is **1** |
| meilisearch | The old index has no version, will be treated as version
**0** in this PR | - |


## Changes

### Split

Splited it into mutiple packages

```text
indexer
├── internal
│   ├── bleve
│   ├── db
│   ├── elasticsearch
│   └── meilisearch
├── code
│   ├── bleve
│   ├── elasticsearch
│   └── internal
└── issues
    ├── bleve
    ├── db
    ├── elasticsearch
    ├── internal
    └── meilisearch
```

- `indexer/interanal`: Internal shared package for indexer.
- `indexer/interanal/[engine]`: Internal shared package for each engine
(bleve/db/elasticsearch/meilisearch).
- `indexer/code`: Implementations for code indexer.
- `indexer/code/internal`: Internal shared package for code indexer.
- `indexer/code/[engine]`: Implementation via each engine for code
indexer.
- `indexer/issues`: Implementations for issues indexer.

### Deduplication

- Combine `Init/Ping/Close` for code indexer and issues indexer.
- ~Combine `issues.indexerHolder` and `code.wrappedIndexer` to
`internal.IndexHolder`.~ Remove it, use dummy indexer instead when the
indexer is not ready.
- Duplicate two copies of creating ES clients.
- Duplicate two copies of `indexerID()`.


### Enhancement

- [x] Support index version for elasticsearch issues indexer, the old
index without version will be treated as version 0.
- [x] Fix spell of `elastic_search/ElasticSearch`, it should be
`Elasticsearch`.
- [x] Improve versioning of ES index. We don't need `Aliases`:
- Gitea does't need aliases for "Zero Downtime" because it never delete
old indexes.
- The old code of issues indexer uses the orignal name to create issue
index, so it's tricky to convert it to an alias.
- [x] Support index version for meilisearch issues indexer, the old
index without version will be treated as version 0.
- [x] Do "ping" only when `Ping` has been called, don't ping
periodically and cache the status.
- [x] Support the context parameter whenever possible.
- [x] Fix outdated example config.
- [x] Give up the requeue logic of issues indexer: When indexing fails,
call Ping to check if it was caused by the engine being unavailable, and
only requeue the task if the engine is unavailable.
- It is fragile and tricky, could cause data losing (It did happen when
I was doing some tests for this PR). And it works for ES only.
- Just always requeue the failed task, if it caused by bad data, it's a
bug of Gitea which should be fixed.

---------

Co-authored-by: Giteabot <teabot@gitea.io>
2023-06-23 12:37:56 +00:00

188 lines
5.7 KiB
Go

// Copyright 2018 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package bleve
import (
"context"
indexer_internal "code.gitea.io/gitea/modules/indexer/internal"
inner_bleve "code.gitea.io/gitea/modules/indexer/internal/bleve"
"code.gitea.io/gitea/modules/indexer/issues/internal"
"github.com/blevesearch/bleve/v2"
"github.com/blevesearch/bleve/v2/analysis/analyzer/custom"
"github.com/blevesearch/bleve/v2/analysis/token/camelcase"
"github.com/blevesearch/bleve/v2/analysis/token/lowercase"
"github.com/blevesearch/bleve/v2/analysis/token/unicodenorm"
"github.com/blevesearch/bleve/v2/analysis/tokenizer/unicode"
"github.com/blevesearch/bleve/v2/mapping"
"github.com/blevesearch/bleve/v2/search/query"
)
const (
issueIndexerAnalyzer = "issueIndexer"
issueIndexerDocType = "issueIndexerDocType"
issueIndexerLatestVersion = 2
)
// numericEqualityQuery a numeric equality query for the given value and field
func numericEqualityQuery(value int64, field string) *query.NumericRangeQuery {
f := float64(value)
tru := true
q := bleve.NewNumericRangeInclusiveQuery(&f, &f, &tru, &tru)
q.SetField(field)
return q
}
func newMatchPhraseQuery(matchPhrase, field, analyzer string) *query.MatchPhraseQuery {
q := bleve.NewMatchPhraseQuery(matchPhrase)
q.FieldVal = field
q.Analyzer = analyzer
return q
}
const unicodeNormalizeName = "unicodeNormalize"
func addUnicodeNormalizeTokenFilter(m *mapping.IndexMappingImpl) error {
return m.AddCustomTokenFilter(unicodeNormalizeName, map[string]interface{}{
"type": unicodenorm.Name,
"form": unicodenorm.NFC,
})
}
const maxBatchSize = 16
// IndexerData an update to the issue indexer
type IndexerData internal.IndexerData
// Type returns the document type, for bleve's mapping.Classifier interface.
func (i *IndexerData) Type() string {
return issueIndexerDocType
}
// generateIssueIndexMapping generates the bleve index mapping for issues
func generateIssueIndexMapping() (mapping.IndexMapping, error) {
mapping := bleve.NewIndexMapping()
docMapping := bleve.NewDocumentMapping()
numericFieldMapping := bleve.NewNumericFieldMapping()
numericFieldMapping.IncludeInAll = false
docMapping.AddFieldMappingsAt("RepoID", numericFieldMapping)
textFieldMapping := bleve.NewTextFieldMapping()
textFieldMapping.Store = false
textFieldMapping.IncludeInAll = false
docMapping.AddFieldMappingsAt("Title", textFieldMapping)
docMapping.AddFieldMappingsAt("Content", textFieldMapping)
docMapping.AddFieldMappingsAt("Comments", textFieldMapping)
if err := addUnicodeNormalizeTokenFilter(mapping); err != nil {
return nil, err
} else if err = mapping.AddCustomAnalyzer(issueIndexerAnalyzer, map[string]interface{}{
"type": custom.Name,
"char_filters": []string{},
"tokenizer": unicode.Name,
"token_filters": []string{unicodeNormalizeName, camelcase.Name, lowercase.Name},
}); err != nil {
return nil, err
}
mapping.DefaultAnalyzer = issueIndexerAnalyzer
mapping.AddDocumentMapping(issueIndexerDocType, docMapping)
mapping.AddDocumentMapping("_all", bleve.NewDocumentDisabledMapping())
return mapping, nil
}
var _ internal.Indexer = &Indexer{}
// Indexer implements Indexer interface
type Indexer struct {
inner *inner_bleve.Indexer
indexer_internal.Indexer // do not composite inner_bleve.Indexer directly to avoid exposing too much
}
// NewIndexer creates a new bleve local indexer
func NewIndexer(indexDir string) *Indexer {
inner := inner_bleve.NewIndexer(indexDir, issueIndexerLatestVersion, generateIssueIndexMapping)
return &Indexer{
Indexer: inner,
inner: inner,
}
}
// Index will save the index data
func (b *Indexer) Index(_ context.Context, issues []*internal.IndexerData) error {
batch := inner_bleve.NewFlushingBatch(b.inner.Indexer, maxBatchSize)
for _, issue := range issues {
if err := batch.Index(indexer_internal.Base36(issue.ID), struct {
RepoID int64
Title string
Content string
Comments []string
}{
RepoID: issue.RepoID,
Title: issue.Title,
Content: issue.Content,
Comments: issue.Comments,
}); err != nil {
return err
}
}
return batch.Flush()
}
// Delete deletes indexes by ids
func (b *Indexer) Delete(_ context.Context, ids ...int64) error {
batch := inner_bleve.NewFlushingBatch(b.inner.Indexer, maxBatchSize)
for _, id := range ids {
if err := batch.Delete(indexer_internal.Base36(id)); err != nil {
return err
}
}
return batch.Flush()
}
// Search searches for issues by given conditions.
// Returns the matching issue IDs
func (b *Indexer) Search(ctx context.Context, keyword string, repoIDs []int64, limit, start int) (*internal.SearchResult, error) {
var repoQueriesP []*query.NumericRangeQuery
for _, repoID := range repoIDs {
repoQueriesP = append(repoQueriesP, numericEqualityQuery(repoID, "RepoID"))
}
repoQueries := make([]query.Query, len(repoQueriesP))
for i, v := range repoQueriesP {
repoQueries[i] = query.Query(v)
}
indexerQuery := bleve.NewConjunctionQuery(
bleve.NewDisjunctionQuery(repoQueries...),
bleve.NewDisjunctionQuery(
newMatchPhraseQuery(keyword, "Title", issueIndexerAnalyzer),
newMatchPhraseQuery(keyword, "Content", issueIndexerAnalyzer),
newMatchPhraseQuery(keyword, "Comments", issueIndexerAnalyzer),
))
search := bleve.NewSearchRequestOptions(indexerQuery, limit, start, false)
search.SortBy([]string{"-_score"})
result, err := b.inner.Indexer.SearchInContext(ctx, search)
if err != nil {
return nil, err
}
ret := internal.SearchResult{
Hits: make([]internal.Match, 0, len(result.Hits)),
}
for _, hit := range result.Hits {
id, err := indexer_internal.ParseBase36(hit.ID)
if err != nil {
return nil, err
}
ret.Hits = append(ret.Hits, internal.Match{
ID: id,
})
}
return &ret, nil
}