Move code indexer related code to a new package (#9191)

* move code indexer related code to a new package

* fix lint

* fix tests

* fix fmt

* GetMaxID support interface parameter

9 files changed, 434 insertions, 379 deletions

diff --git a/integrations/repo_search_test.go b/integrations/repo_search_test.go
index eb843525fb..701013735c 100644
--- a/integrations/repo_search_test.go
+++ b/integrations/repo_search_test.go
@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"code.gitea.io/gitea/models"
+	code_indexer "code.gitea.io/gitea/modules/indexer/code"
 	"code.gitea.io/gitea/modules/setting"
 
 	"github.com/PuerkitoBio/goquery"
@@ -34,7 +35,7 @@ func TestSearchRepo(t *testing.T) {
 	repo, err := models.GetRepositoryByOwnerAndName("user2", "repo1")
 	assert.NoError(t, err)
 
-	executeIndexer(t, repo, models.UpdateRepoIndexer)
+	executeIndexer(t, repo, code_indexer.UpdateRepoIndexer)
 
 	testSearch(t, "/user2/repo1/search?q=Description&page=1", []string{"README.md"})
 
@@ -44,8 +45,8 @@ func TestSearchRepo(t *testing.T) {
 	repo, err = models.GetRepositoryByOwnerAndName("user2", "glob")
 	assert.NoError(t, err)
 
-	executeIndexer(t, repo, models.DeleteRepoFromIndexer)
-	executeIndexer(t, repo, models.UpdateRepoIndexer)
+	executeIndexer(t, repo, code_indexer.DeleteRepoFromIndexer)
+	executeIndexer(t, repo, code_indexer.UpdateRepoIndexer)
 
 	testSearch(t, "/user2/glob/search?q=loren&page=1", []string{"a.txt"})
 	testSearch(t, "/user2/glob/search?q=file3&page=1", []string{"x/b.txt"})
diff --git a/models/models.go b/models/models.go
index 854cb33b14..8c10e7abfc 100644
--- a/models/models.go
+++ b/models/models.go
@@ -254,3 +254,28 @@ func MaxBatchInsertSize(bean interface{}) int {
 func Count(bean interface{}) (int64, error) {
 	return x.Count(bean)
 }
+
+// IsTableNotEmpty returns true if table has at least one record
+func IsTableNotEmpty(tableName string) (bool, error) {
+	return x.Table(tableName).Exist()
+}
+
+// DeleteAllRecords will delete all the records of this table
+func DeleteAllRecords(tableName string) error {
+	_, err := x.Exec(fmt.Sprintf("DELETE FROM %s", tableName))
+	return err
+}
+
+// GetMaxID will return max id of the table
+func GetMaxID(beanOrTableName interface{}) (maxID int64, err error) {
+	_, err = x.Select("MAX(id)").Table(beanOrTableName).Get(&maxID)
+	return
+}
+
+// FindByMaxID filled results as the condition from database
+func FindByMaxID(maxID int64, limit int, results interface{}) error {
+	return x.Where("id <= ?", maxID).
+		OrderBy("id DESC").
+		Limit(limit).
+		Find(results)
+}
diff --git a/models/repo.go b/models/repo.go
index 2fd4df9206..e809bafa30 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -1112,10 +1112,6 @@ func MigrateRepositoryGitData(doer, u *User, repo *Repository, opts api.MigrateR
 		repo, err = CleanUpMigrateInfo(repo)
 	}
 
-	if err != nil && !repo.IsEmpty {
-		UpdateRepoIndexer(repo)
-	}
-
 	return repo, err
 }
 
diff --git a/models/repo_indexer.go b/models/repo_indexer.go
index 4085982c26..138ef54d33 100644
--- a/models/repo_indexer.go
+++ b/models/repo_indexer.go
@@ -4,23 +4,6 @@
 
 package models
 
-import (
-	"fmt"
-	"strconv"
-	"strings"
-	"time"
-
-	"code.gitea.io/gitea/modules/base"
-	"code.gitea.io/gitea/modules/charset"
-	"code.gitea.io/gitea/modules/git"
-	"code.gitea.io/gitea/modules/graceful"
-	"code.gitea.io/gitea/modules/indexer"
-	"code.gitea.io/gitea/modules/log"
-	"code.gitea.io/gitea/modules/setting"
-
-	"github.com/ethantkoenig/rupture"
-)
-
 // RepoIndexerStatus status of a repo's entry in the repo indexer
 // For now, implicitly refers to default branch
 type RepoIndexerStatus struct {
@@ -29,7 +12,8 @@ type RepoIndexerStatus struct {
 	CommitSha string `xorm:"VARCHAR(40)"`
 }
 
-func (repo *Repository) getIndexerStatus() error {
+// GetIndexerStatus loads repo codes indxer status
+func (repo *Repository) GetIndexerStatus() error {
 	if repo.IndexerStatus != nil {
 		return nil
 	}
@@ -44,8 +28,9 @@ func (repo *Repository) getIndexerStatus() error {
 	return nil
 }
 
-func (repo *Repository) updateIndexerStatus(sha string) error {
-	if err := repo.getIndexerStatus(); err != nil {
+// UpdateIndexerStatus updates indexer status
+func (repo *Repository) UpdateIndexerStatus(sha string) error {
+	if err := repo.GetIndexerStatus(); err != nil {
 		return err
 	}
 	if len(repo.IndexerStatus.CommitSha) == 0 {
@@ -58,349 +43,3 @@ func (repo *Repository) updateIndexerStatus(sha string) error {
 		Update(repo.IndexerStatus)
 	return err
 }
-
-type repoIndexerOperation struct {
-	repoID   int64
-	deleted  bool
-	watchers []chan<- error
-}
-
-var repoIndexerOperationQueue chan repoIndexerOperation
-
-// InitRepoIndexer initialize the repo indexer
-func InitRepoIndexer() {
-	if !setting.Indexer.RepoIndexerEnabled {
-		return
-	}
-	waitChannel := make(chan time.Duration)
-	repoIndexerOperationQueue = make(chan repoIndexerOperation, setting.Indexer.UpdateQueueLength)
-	go func() {
-		start := time.Now()
-		log.Info("Initializing Repository Indexer")
-		indexer.InitRepoIndexer(populateRepoIndexerAsynchronously)
-		go processRepoIndexerOperationQueue()
-		waitChannel <- time.Since(start)
-	}()
-	if setting.Indexer.StartupTimeout > 0 {
-		go func() {
-			timeout := setting.Indexer.StartupTimeout
-			if graceful.Manager.IsChild() && setting.GracefulHammerTime > 0 {
-				timeout += setting.GracefulHammerTime
-			}
-			select {
-			case duration := <-waitChannel:
-				log.Info("Repository Indexer Initialization took %v", duration)
-			case <-time.After(timeout):
-				log.Fatal("Repository Indexer Initialization Timed-Out after: %v", timeout)
-			}
-		}()
-
-	}
-}
-
-// populateRepoIndexerAsynchronously asynchronously populates the repo indexer
-// with pre-existing data. This should only be run when the indexer is created
-// for the first time.
-func populateRepoIndexerAsynchronously() error {
-	exist, err := x.Table("repository").Exist()
-	if err != nil {
-		return err
-	} else if !exist {
-		return nil
-	}
-
-	// if there is any existing repo indexer metadata in the DB, delete it
-	// since we are starting afresh. Also, xorm requires deletes to have a
-	// condition, and we want to delete everything, thus 1=1.
-	if _, err := x.Where("1=1").Delete(new(RepoIndexerStatus)); err != nil {
-		return err
-	}
-
-	var maxRepoID int64
-	if _, err = x.Select("MAX(id)").Table("repository").Get(&maxRepoID); err != nil {
-		return err
-	}
-	go populateRepoIndexer(maxRepoID)
-	return nil
-}
-
-// populateRepoIndexer populate the repo indexer with pre-existing data. This
-// should only be run when the indexer is created for the first time.
-func populateRepoIndexer(maxRepoID int64) {
-	log.Info("Populating the repo indexer with existing repositories")
-	// start with the maximum existing repo ID and work backwards, so that we
-	// don't include repos that are created after gitea starts; such repos will
-	// already be added to the indexer, and we don't need to add them again.
-	for maxRepoID > 0 {
-		repos := make([]*Repository, 0, RepositoryListDefaultPageSize)
-		err := x.Where("id <= ?", maxRepoID).
-			OrderBy("id DESC").
-			Limit(RepositoryListDefaultPageSize).
-			Find(&repos)
-		if err != nil {
-			log.Error("populateRepoIndexer: %v", err)
-			return
-		} else if len(repos) == 0 {
-			break
-		}
-		for _, repo := range repos {
-			repoIndexerOperationQueue <- repoIndexerOperation{
-				repoID:  repo.ID,
-				deleted: false,
-			}
-			maxRepoID = repo.ID - 1
-		}
-	}
-	log.Info("Done populating the repo indexer with existing repositories")
-}
-
-func updateRepoIndexer(repoID int64) error {
-	repo, err := getRepositoryByID(x, repoID)
-	if err != nil {
-		return err
-	}
-
-	sha, err := getDefaultBranchSha(repo)
-	if err != nil {
-		return err
-	}
-	changes, err := getRepoChanges(repo, sha)
-	if err != nil {
-		return err
-	} else if changes == nil {
-		return nil
-	}
-
-	batch := indexer.RepoIndexerBatch()
-	for _, update := range changes.Updates {
-		if err := addUpdate(update, repo, batch); err != nil {
-			return err
-		}
-	}
-	for _, filename := range changes.RemovedFilenames {
-		if err := addDelete(filename, repo, batch); err != nil {
-			return err
-		}
-	}
-	if err = batch.Flush(); err != nil {
-		return err
-	}
-	return repo.updateIndexerStatus(sha)
-}
-
-// repoChanges changes (file additions/updates/removals) to a repo
-type repoChanges struct {
-	Updates          []fileUpdate
-	RemovedFilenames []string
-}
-
-type fileUpdate struct {
-	Filename string
-	BlobSha  string
-}
-
-func getDefaultBranchSha(repo *Repository) (string, error) {
-	stdout, err := git.NewCommand("show-ref", "-s", repo.DefaultBranch).RunInDir(repo.RepoPath())
-	if err != nil {
-		return "", err
-	}
-	return strings.TrimSpace(stdout), nil
-}
-
-// getRepoChanges returns changes to repo since last indexer update
-func getRepoChanges(repo *Repository, revision string) (*repoChanges, error) {
-	if err := repo.getIndexerStatus(); err != nil {
-		return nil, err
-	}
-
-	if len(repo.IndexerStatus.CommitSha) == 0 {
-		return genesisChanges(repo, revision)
-	}
-	return nonGenesisChanges(repo, revision)
-}
-
-func addUpdate(update fileUpdate, repo *Repository, batch rupture.FlushingBatch) error {
-	stdout, err := git.NewCommand("cat-file", "-s", update.BlobSha).
-		RunInDir(repo.RepoPath())
-	if err != nil {
-		return err
-	}
-	if size, err := strconv.Atoi(strings.TrimSpace(stdout)); err != nil {
-		return fmt.Errorf("Misformatted git cat-file output: %v", err)
-	} else if int64(size) > setting.Indexer.MaxIndexerFileSize {
-		return addDelete(update.Filename, repo, batch)
-	}
-
-	fileContents, err := git.NewCommand("cat-file", "blob", update.BlobSha).
-		RunInDirBytes(repo.RepoPath())
-	if err != nil {
-		return err
-	} else if !base.IsTextFile(fileContents) {
-		// FIXME: UTF-16 files will probably fail here
-		return nil
-	}
-	indexerUpdate := indexer.RepoIndexerUpdate{
-		Filepath: update.Filename,
-		Op:       indexer.RepoIndexerOpUpdate,
-		Data: &indexer.RepoIndexerData{
-			RepoID:  repo.ID,
-			Content: string(charset.ToUTF8DropErrors(fileContents)),
-		},
-	}
-	return indexerUpdate.AddToFlushingBatch(batch)
-}
-
-func addDelete(filename string, repo *Repository, batch rupture.FlushingBatch) error {
-	indexerUpdate := indexer.RepoIndexerUpdate{
-		Filepath: filename,
-		Op:       indexer.RepoIndexerOpDelete,
-		Data: &indexer.RepoIndexerData{
-			RepoID: repo.ID,
-		},
-	}
-	return indexerUpdate.AddToFlushingBatch(batch)
-}
-
-func isIndexable(entry *git.TreeEntry) bool {
-	if !entry.IsRegular() && !entry.IsExecutable() {
-		return false
-	}
-	name := strings.ToLower(entry.Name())
-	for _, g := range setting.Indexer.ExcludePatterns {
-		if g.Match(name) {
-			return false
-		}
-	}
-	for _, g := range setting.Indexer.IncludePatterns {
-		if g.Match(name) {
-			return true
-		}
-	}
-	return len(setting.Indexer.IncludePatterns) == 0
-}
-
-// parseGitLsTreeOutput parses the output of a `git ls-tree -r --full-name` command
-func parseGitLsTreeOutput(stdout []byte) ([]fileUpdate, error) {
-	entries, err := git.ParseTreeEntries(stdout)
-	if err != nil {
-		return nil, err
-	}
-	var idxCount = 0
-	updates := make([]fileUpdate, len(entries))
-	for _, entry := range entries {
-		if isIndexable(entry) {
-			updates[idxCount] = fileUpdate{
-				Filename: entry.Name(),
-				BlobSha:  entry.ID.String(),
-			}
-			idxCount++
-		}
-	}
-	return updates[:idxCount], nil
-}
-
-// genesisChanges get changes to add repo to the indexer for the first time
-func genesisChanges(repo *Repository, revision string) (*repoChanges, error) {
-	var changes repoChanges
-	stdout, err := git.NewCommand("ls-tree", "--full-tree", "-r", revision).
-		RunInDirBytes(repo.RepoPath())
-	if err != nil {
-		return nil, err
-	}
-	changes.Updates, err = parseGitLsTreeOutput(stdout)
-	return &changes, err
-}
-
-// nonGenesisChanges get changes since the previous indexer update
-func nonGenesisChanges(repo *Repository, revision string) (*repoChanges, error) {
-	diffCmd := git.NewCommand("diff", "--name-status",
-		repo.IndexerStatus.CommitSha, revision)
-	stdout, err := diffCmd.RunInDir(repo.RepoPath())
-	if err != nil {
-		// previous commit sha may have been removed by a force push, so
-		// try rebuilding from scratch
-		log.Warn("git diff: %v", err)
-		if err = indexer.DeleteRepoFromIndexer(repo.ID); err != nil {
-			return nil, err
-		}
-		return genesisChanges(repo, revision)
-	}
-	var changes repoChanges
-	updatedFilenames := make([]string, 0, 10)
-	for _, line := range strings.Split(stdout, "\n") {
-		line = strings.TrimSpace(line)
-		if len(line) == 0 {
-			continue
-		}
-		filename := strings.TrimSpace(line[1:])
-		if len(filename) == 0 {
-			continue
-		} else if filename[0] == '"' {
-			filename, err = strconv.Unquote(filename)
-			if err != nil {
-				return nil, err
-			}
-		}
-
-		switch status := line[0]; status {
-		case 'M', 'A':
-			updatedFilenames = append(updatedFilenames, filename)
-		case 'D':
-			changes.RemovedFilenames = append(changes.RemovedFilenames, filename)
-		default:
-			log.Warn("Unrecognized status: %c (line=%s)", status, line)
-		}
-	}
-
-	cmd := git.NewCommand("ls-tree", "--full-tree", revision, "--")
-	cmd.AddArguments(updatedFilenames...)
-	lsTreeStdout, err := cmd.RunInDirBytes(repo.RepoPath())
-	if err != nil {
-		return nil, err
-	}
-	changes.Updates, err = parseGitLsTreeOutput(lsTreeStdout)
-	return &changes, err
-}
-
-func processRepoIndexerOperationQueue() {
-	for {
-		op := <-repoIndexerOperationQueue
-		var err error
-		if op.deleted {
-			if err = indexer.DeleteRepoFromIndexer(op.repoID); err != nil {
-				log.Error("DeleteRepoFromIndexer: %v", err)
-			}
-		} else {
-			if err = updateRepoIndexer(op.repoID); err != nil {
-				log.Error("updateRepoIndexer: %v", err)
-			}
-		}
-		for _, watcher := range op.watchers {
-			watcher <- err
-		}
-	}
-}
-
-// DeleteRepoFromIndexer remove all of a repository's entries from the indexer
-func DeleteRepoFromIndexer(repo *Repository, watchers ...chan<- error) {
-	addOperationToQueue(repoIndexerOperation{repoID: repo.ID, deleted: true, watchers: watchers})
-}
-
-// UpdateRepoIndexer update a repository's entries in the indexer
-func UpdateRepoIndexer(repo *Repository, watchers ...chan<- error) {
-	addOperationToQueue(repoIndexerOperation{repoID: repo.ID, deleted: false, watchers: watchers})
-}
-
-func addOperationToQueue(op repoIndexerOperation) {
-	if !setting.Indexer.RepoIndexerEnabled {
-		return
-	}
-	select {
-	case repoIndexerOperationQueue <- op:
-		break
-	default:
-		go func() {
-			repoIndexerOperationQueue <- op
-		}()
-	}
-}
diff --git a/modules/indexer/code/bleve.go b/modules/indexer/code/bleve.go
new file mode 100644
index 0000000000..4e7eaa21b7
--- /dev/null
+++ b/modules/indexer/code/bleve.go
@@ -0,0 +1,365 @@
+// Copyright 2019 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 code
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/charset"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/graceful"
+	"code.gitea.io/gitea/modules/indexer"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+	"github.com/ethantkoenig/rupture"
+)
+
+type repoIndexerOperation struct {
+	repoID   int64
+	deleted  bool
+	watchers []chan<- error
+}
+
+var repoIndexerOperationQueue chan repoIndexerOperation
+
+// InitRepoIndexer initialize the repo indexer
+func InitRepoIndexer() {
+	if !setting.Indexer.RepoIndexerEnabled {
+		return
+	}
+	waitChannel := make(chan time.Duration)
+	repoIndexerOperationQueue = make(chan repoIndexerOperation, setting.Indexer.UpdateQueueLength)
+	go func() {
+		start := time.Now()
+		log.Info("Initializing Repository Indexer")
+		indexer.InitRepoIndexer(populateRepoIndexerAsynchronously)
+		go processRepoIndexerOperationQueue()
+		waitChannel <- time.Since(start)
+	}()
+	if setting.Indexer.StartupTimeout > 0 {
+		go func() {
+			timeout := setting.Indexer.StartupTimeout
+			if graceful.Manager.IsChild() && setting.GracefulHammerTime > 0 {
+				timeout += setting.GracefulHammerTime
+			}
+			select {
+			case duration := <-waitChannel:
+				log.Info("Repository Indexer Initialization took %v", duration)
+			case <-time.After(timeout):
+				log.Fatal("Repository Indexer Initialization Timed-Out after: %v", timeout)
+			}
+		}()
+
+	}
+}
+
+// populateRepoIndexerAsynchronously asynchronously populates the repo indexer
+// with pre-existing data. This should only be run when the indexer is created
+// for the first time.
+func populateRepoIndexerAsynchronously() error {
+	exist, err := models.IsTableNotEmpty("repository")
+	if err != nil {
+		return err
+	} else if !exist {
+		return nil
+	}
+
+	// if there is any existing repo indexer metadata in the DB, delete it
+	// since we are starting afresh. Also, xorm requires deletes to have a
+	// condition, and we want to delete everything, thus 1=1.
+	if err := models.DeleteAllRecords("repo_indexer_status"); err != nil {
+		return err
+	}
+
+	var maxRepoID int64
+	if maxRepoID, err = models.GetMaxID("repository"); err != nil {
+		return err
+	}
+	go populateRepoIndexer(maxRepoID)
+	return nil
+}
+
+// populateRepoIndexer populate the repo indexer with pre-existing data. This
+// should only be run when the indexer is created for the first time.
+func populateRepoIndexer(maxRepoID int64) {
+	log.Info("Populating the repo indexer with existing repositories")
+	// start with the maximum existing repo ID and work backwards, so that we
+	// don't include repos that are created after gitea starts; such repos will
+	// already be added to the indexer, and we don't need to add them again.
+	for maxRepoID > 0 {
+		repos := make([]*models.Repository, 0, models.RepositoryListDefaultPageSize)
+		err := models.FindByMaxID(maxRepoID, models.RepositoryListDefaultPageSize, &repos)
+		if err != nil {
+			log.Error("populateRepoIndexer: %v", err)
+			return
+		} else if len(repos) == 0 {
+			break
+		}
+		for _, repo := range repos {
+			repoIndexerOperationQueue <- repoIndexerOperation{
+				repoID:  repo.ID,
+				deleted: false,
+			}
+			maxRepoID = repo.ID - 1
+		}
+	}
+	log.Info("Done populating the repo indexer with existing repositories")
+}
+
+func updateRepoIndexer(repoID int64) error {
+	repo, err := models.GetRepositoryByID(repoID)
+	if err != nil {
+		return err
+	}
+
+	sha, err := getDefaultBranchSha(repo)
+	if err != nil {
+		return err
+	}
+	changes, err := getRepoChanges(repo, sha)
+	if err != nil {
+		return err
+	} else if changes == nil {
+		return nil
+	}
+
+	batch := indexer.RepoIndexerBatch()
+	for _, update := range changes.Updates {
+		if err := addUpdate(update, repo, batch); err != nil {
+			return err
+		}
+	}
+	for _, filename := range changes.RemovedFilenames {
+		if err := addDelete(filename, repo, batch); err != nil {
+			return err
+		}
+	}
+	if err = batch.Flush(); err != nil {
+		return err
+	}
+	return repo.UpdateIndexerStatus(sha)
+}
+
+// repoChanges changes (file additions/updates/removals) to a repo
+type repoChanges struct {
+	Updates          []fileUpdate
+	RemovedFilenames []string
+}
+
+type fileUpdate struct {
+	Filename string
+	BlobSha  string
+}
+
+func getDefaultBranchSha(repo *models.Repository) (string, error) {
+	stdout, err := git.NewCommand("show-ref", "-s", repo.DefaultBranch).RunInDir(repo.RepoPath())
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(stdout), nil
+}
+
+// getRepoChanges returns changes to repo since last indexer update
+func getRepoChanges(repo *models.Repository, revision string) (*repoChanges, error) {
+	if err := repo.GetIndexerStatus(); err != nil {
+		return nil, err
+	}
+
+	if len(repo.IndexerStatus.CommitSha) == 0 {
+		return genesisChanges(repo, revision)
+	}
+	return nonGenesisChanges(repo, revision)
+}
+
+func addUpdate(update fileUpdate, repo *models.Repository, batch rupture.FlushingBatch) error {
+	stdout, err := git.NewCommand("cat-file", "-s", update.BlobSha).
+		RunInDir(repo.RepoPath())
+	if err != nil {
+		return err
+	}
+	if size, err := strconv.Atoi(strings.TrimSpace(stdout)); err != nil {
+		return fmt.Errorf("Misformatted git cat-file output: %v", err)
+	} else if int64(size) > setting.Indexer.MaxIndexerFileSize {
+		return addDelete(update.Filename, repo, batch)
+	}
+
+	fileContents, err := git.NewCommand("cat-file", "blob", update.BlobSha).
+		RunInDirBytes(repo.RepoPath())
+	if err != nil {
+		return err
+	} else if !base.IsTextFile(fileContents) {
+		// FIXME: UTF-16 files will probably fail here
+		return nil
+	}
+	indexerUpdate := indexer.RepoIndexerUpdate{
+		Filepath: update.Filename,
+		Op:       indexer.RepoIndexerOpUpdate,
+		Data: &indexer.RepoIndexerData{
+			RepoID:  repo.ID,
+			Content: string(charset.ToUTF8DropErrors(fileContents)),
+		},
+	}
+	return indexerUpdate.AddToFlushingBatch(batch)
+}
+
+func addDelete(filename string, repo *models.Repository, batch rupture.FlushingBatch) error {
+	indexerUpdate := indexer.RepoIndexerUpdate{
+		Filepath: filename,
+		Op:       indexer.RepoIndexerOpDelete,
+		Data: &indexer.RepoIndexerData{
+			RepoID: repo.ID,
+		},
+	}
+	return indexerUpdate.AddToFlushingBatch(batch)
+}
+
+func isIndexable(entry *git.TreeEntry) bool {
+	if !entry.IsRegular() && !entry.IsExecutable() {
+		return false
+	}
+	name := strings.ToLower(entry.Name())
+	for _, g := range setting.Indexer.ExcludePatterns {
+		if g.Match(name) {
+			return false
+		}
+	}
+	for _, g := range setting.Indexer.IncludePatterns {
+		if g.Match(name) {
+			return true
+		}
+	}
+	return len(setting.Indexer.IncludePatterns) == 0
+}
+
+// parseGitLsTreeOutput parses the output of a `git ls-tree -r --full-name` command
+func parseGitLsTreeOutput(stdout []byte) ([]fileUpdate, error) {
+	entries, err := git.ParseTreeEntries(stdout)
+	if err != nil {
+		return nil, err
+	}
+	var idxCount = 0
+	updates := make([]fileUpdate, len(entries))
+	for _, entry := range entries {
+		if isIndexable(entry) {
+			updates[idxCount] = fileUpdate{
+				Filename: entry.Name(),
+				BlobSha:  entry.ID.String(),
+			}
+			idxCount++
+		}
+	}
+	return updates[:idxCount], nil
+}
+
+// genesisChanges get changes to add repo to the indexer for the first time
+func genesisChanges(repo *models.Repository, revision string) (*repoChanges, error) {
+	var changes repoChanges
+	stdout, err := git.NewCommand("ls-tree", "--full-tree", "-r", revision).
+		RunInDirBytes(repo.RepoPath())
+	if err != nil {
+		return nil, err
+	}
+	changes.Updates, err = parseGitLsTreeOutput(stdout)
+	return &changes, err
+}
+
+// nonGenesisChanges get changes since the previous indexer update
+func nonGenesisChanges(repo *models.Repository, revision string) (*repoChanges, error) {
+	diffCmd := git.NewCommand("diff", "--name-status",
+		repo.IndexerStatus.CommitSha, revision)
+	stdout, err := diffCmd.RunInDir(repo.RepoPath())
+	if err != nil {
+		// previous commit sha may have been removed by a force push, so
+		// try rebuilding from scratch
+		log.Warn("git diff: %v", err)
+		if err = indexer.DeleteRepoFromIndexer(repo.ID); err != nil {
+			return nil, err
+		}
+		return genesisChanges(repo, revision)
+	}
+	var changes repoChanges
+	updatedFilenames := make([]string, 0, 10)
+	for _, line := range strings.Split(stdout, "\n") {
+		line = strings.TrimSpace(line)
+		if len(line) == 0 {
+			continue
+		}
+		filename := strings.TrimSpace(line[1:])
+		if len(filename) == 0 {
+			continue
+		} else if filename[0] == '"' {
+			filename, err = strconv.Unquote(filename)
+			if err != nil {
+				return nil, err
+			}
+		}
+
+		switch status := line[0]; status {
+		case 'M', 'A':
+			updatedFilenames = append(updatedFilenames, filename)
+		case 'D':
+			changes.RemovedFilenames = append(changes.RemovedFilenames, filename)
+		default:
+			log.Warn("Unrecognized status: %c (line=%s)", status, line)
+		}
+	}
+
+	cmd := git.NewCommand("ls-tree", "--full-tree", revision, "--")
+	cmd.AddArguments(updatedFilenames...)
+	lsTreeStdout, err := cmd.RunInDirBytes(repo.RepoPath())
+	if err != nil {
+		return nil, err
+	}
+	changes.Updates, err = parseGitLsTreeOutput(lsTreeStdout)
+	return &changes, err
+}
+
+func processRepoIndexerOperationQueue() {
+	for {
+		op := <-repoIndexerOperationQueue
+		var err error
+		if op.deleted {
+			if err = indexer.DeleteRepoFromIndexer(op.repoID); err != nil {
+				log.Error("DeleteRepoFromIndexer: %v", err)
+			}
+		} else {
+			if err = updateRepoIndexer(op.repoID); err != nil {
+				log.Error("updateRepoIndexer: %v", err)
+			}
+		}
+		for _, watcher := range op.watchers {
+			watcher <- err
+		}
+	}
+}
+
+// DeleteRepoFromIndexer remove all of a repository's entries from the indexer
+func DeleteRepoFromIndexer(repo *models.Repository, watchers ...chan<- error) {
+	addOperationToQueue(repoIndexerOperation{repoID: repo.ID, deleted: true, watchers: watchers})
+}
+
+// UpdateRepoIndexer update a repository's entries in the indexer
+func UpdateRepoIndexer(repo *models.Repository, watchers ...chan<- error) {
+	addOperationToQueue(repoIndexerOperation{repoID: repo.ID, deleted: false, watchers: watchers})
+}
+
+func addOperationToQueue(op repoIndexerOperation) {
+	if !setting.Indexer.RepoIndexerEnabled {
+		return
+	}
+	select {
+	case repoIndexerOperationQueue <- op:
+		break
+	default:
+		go func() {
+			repoIndexerOperationQueue <- op
+		}()
+	}
+}
diff --git a/modules/indexer/code/bleve_test.go b/modules/indexer/code/bleve_test.go
new file mode 100644
index 0000000000..2eafeef3c5
--- /dev/null
+++ b/modules/indexer/code/bleve_test.go
@@ -0,0 +1,16 @@
+// Copyright 2019 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 code
+
+import (
+	"path/filepath"
+	"testing"
+
+	"code.gitea.io/gitea/models"
+)
+
+func TestMain(m *testing.M) {
+	models.MainTest(m, filepath.Join("..", "..", ".."))
+}
diff --git a/modules/notification/indexer/indexer.go b/modules/notification/indexer/indexer.go
index 13baa76ac0..0e76dde539 100644
--- a/modules/notification/indexer/indexer.go
+++ b/modules/notification/indexer/indexer.go
@@ -6,9 +6,11 @@ package indexer
 
 import (
 	"code.gitea.io/gitea/models"
+	code_indexer "code.gitea.io/gitea/modules/indexer/code"
 	issue_indexer "code.gitea.io/gitea/modules/indexer/issues"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/notification/base"
+	"code.gitea.io/gitea/modules/setting"
 )
 
 type indexerNotifier struct {
@@ -103,7 +105,21 @@ func (r *indexerNotifier) NotifyDeleteComment(doer *models.User, comment *models
 
 func (r *indexerNotifier) NotifyDeleteRepository(doer *models.User, repo *models.Repository) {
 	issue_indexer.DeleteRepoIssueIndexer(repo)
-	models.DeleteRepoFromIndexer(repo)
+	if setting.Indexer.RepoIndexerEnabled {
+		code_indexer.DeleteRepoFromIndexer(repo)
+	}
+}
+
+func (r *indexerNotifier) NotifyMigrateRepository(doer *models.User, u *models.User, repo *models.Repository) {
+	if setting.Indexer.RepoIndexerEnabled && !repo.IsEmpty {
+		code_indexer.UpdateRepoIndexer(repo)
+	}
+}
+
+func (r *indexerNotifier) NotifyPushCommits(pusher *models.User, repo *models.Repository, refName, oldCommitID, newCommitID string, commits *models.PushCommits) {
+	if setting.Indexer.RepoIndexerEnabled && refName == repo.DefaultBranch {
+		code_indexer.UpdateRepoIndexer(repo)
+	}
 }
 
 func (r *indexerNotifier) NotifyIssueChangeContent(doer *models.User, issue *models.Issue, oldContent string) {
diff --git a/modules/repofiles/update.go b/modules/repofiles/update.go
index c1eae53099..0042be52cd 100644
--- a/modules/repofiles/update.go
+++ b/modules/repofiles/update.go
@@ -513,10 +513,6 @@ func PushUpdate(repo *models.Repository, branch string, opts PushUpdateOptions)
 
 	go pull_service.AddTestPullRequestTask(pusher, repo.ID, branch, true)
 
-	if opts.RefFullName == git.BranchPrefix+repo.DefaultBranch {
-		models.UpdateRepoIndexer(repo)
-	}
-
 	if err = models.WatchIfAuto(opts.PusherID, repo.ID, true); err != nil {
 		log.Warn("Fail to perform auto watch on user %v for repo %v: %v", opts.PusherID, repo.ID, err)
 	}
diff --git a/routers/init.go b/routers/init.go
index 447c168852..81418a4ad5 100644
--- a/routers/init.go
+++ b/routers/init.go
@@ -15,6 +15,7 @@ import (
 	"code.gitea.io/gitea/modules/cron"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/highlight"
+	code_indexer "code.gitea.io/gitea/modules/indexer/code"
 	issue_indexer "code.gitea.io/gitea/modules/indexer/issues"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/markup"
@@ -102,7 +103,7 @@ func GlobalInit() {
 		// Booting long running goroutines.
 		cron.NewContext()
 		issue_indexer.InitIssueIndexer(false)
-		models.InitRepoIndexer()
+		code_indexer.InitRepoIndexer()
 		mirror_service.InitSyncMirrors()
 		webhook.InitDeliverHooks()
 		pull_service.Init()