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

2 files changed, 381 insertions, 0 deletions

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("..", "..", ".."))
+}