Fix data race in bleve indexer (#16474)

* Fix data race in bleve indexer

modules/indexer/bleve/batch.go

@@ -0,0 +1,59 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+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
+}

modules/indexer/code/bleve.go

@@ -18,6 +18,7 @@ import (
 	"code.gitea.io/gitea/modules/analyze"
 	"code.gitea.io/gitea/modules/charset"
 	"code.gitea.io/gitea/modules/git"
+	gitea_bleve "code.gitea.io/gitea/modules/indexer/bleve"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/timeutil"
@@ -176,7 +177,8 @@ func NewBleveIndexer(indexDir string) (*BleveIndexer, bool, error) {
 	return indexer, created, err
 }
 
-func (b *BleveIndexer) addUpdate(batchWriter git.WriteCloserError, batchReader *bufio.Reader, commitSha string, update fileUpdate, repo *models.Repository, batch rupture.FlushingBatch) error {
+func (b *BleveIndexer) addUpdate(batchWriter git.WriteCloserError, batchReader *bufio.Reader, commitSha string,
+	update fileUpdate, repo *models.Repository, batch *gitea_bleve.FlushingBatch) error {
 	// Ignore vendored files in code search
 	if setting.Indexer.ExcludeVendored && analyze.IsVendor(update.Filename) {
 		return nil
@@ -229,7 +231,7 @@ func (b *BleveIndexer) addUpdate(batchWriter git.WriteCloserError, batchReader *
 	})
 }
 
-func (b *BleveIndexer) addDelete(filename string, repo *models.Repository, batch rupture.FlushingBatch) error {
+func (b *BleveIndexer) addDelete(filename string, repo *models.Repository, batch *gitea_bleve.FlushingBatch) error {
 	id := filenameIndexerID(repo.ID, filename)
 	return batch.Delete(id)
 }
@@ -267,7 +269,7 @@ func (b *BleveIndexer) Close() {
 
 // Index indexes the data
 func (b *BleveIndexer) Index(repo *models.Repository, sha string, changes *repoChanges) error {
-	batch := rupture.NewFlushingBatch(b.indexer, maxBatchSize)
+	batch := gitea_bleve.NewFlushingBatch(b.indexer, maxBatchSize)
 	if len(changes.Updates) > 0 {
 
 		batchWriter, batchReader, cancel := git.CatFileBatch(repo.RepoPath())
@@ -296,7 +298,7 @@ func (b *BleveIndexer) Delete(repoID int64) error {
 	if err != nil {
 		return err
 	}
-	batch := rupture.NewFlushingBatch(b.indexer, maxBatchSize)
+	batch := gitea_bleve.NewFlushingBatch(b.indexer, maxBatchSize)
 	for _, hit := range result.Hits {
 		if err = batch.Delete(hit.ID); err != nil {
 			return err

modules/indexer/issues/bleve.go

@@ -9,8 +9,10 @@ import (
 	"os"
 	"strconv"
 
+	gitea_bleve "code.gitea.io/gitea/modules/indexer/bleve"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/util"
+
 	"github.com/blevesearch/bleve/v2"
 	"github.com/blevesearch/bleve/v2/analysis/analyzer/custom"
 	"github.com/blevesearch/bleve/v2/analysis/token/lowercase"
@@ -197,7 +199,7 @@ func (b *BleveIndexer) Close() {
 
 // Index will save the index data
 func (b *BleveIndexer) Index(issues []*IndexerData) error {
-	batch := rupture.NewFlushingBatch(b.indexer, maxBatchSize)
+	batch := gitea_bleve.NewFlushingBatch(b.indexer, maxBatchSize)
 	for _, issue := range issues {
 		if err := batch.Index(indexerID(issue.ID), struct {
 			RepoID   int64
@@ -218,7 +220,7 @@ func (b *BleveIndexer) Index(issues []*IndexerData) error {
 
 // Delete deletes indexes by ids
 func (b *BleveIndexer) Delete(ids ...int64) error {
-	batch := rupture.NewFlushingBatch(b.indexer, maxBatchSize)
+	batch := gitea_bleve.NewFlushingBatch(b.indexer, maxBatchSize)
 	for _, id := range ids {
 		if err := batch.Delete(indexerID(id)); err != nil {
 			return err