1 files changed, 123 insertions, 0 deletions
diff --git a/services/repository/lfs.go b/services/repository/lfs.go
new file mode 100644
index 0000000..4cd1110
--- /dev/null
+++ b/services/repository/lfs.go
@@ -0,0 +1,123 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package repository
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	git_model "code.gitea.io/gitea/models/git"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
+	"code.gitea.io/gitea/modules/lfs"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/timeutil"
+)
+
+// GarbageCollectLFSMetaObjectsOptions provides options for GarbageCollectLFSMetaObjects function
+type GarbageCollectLFSMetaObjectsOptions struct {
+	LogDetail               func(format string, v ...any)
+	AutoFix                 bool
+	OlderThan               time.Time
+	UpdatedLessRecentlyThan time.Time
+}
+
+// GarbageCollectLFSMetaObjects garbage collects LFS objects for all repositories
+func GarbageCollectLFSMetaObjects(ctx context.Context, opts GarbageCollectLFSMetaObjectsOptions) error {
+	log.Trace("Doing: GarbageCollectLFSMetaObjects")
+	defer log.Trace("Finished: GarbageCollectLFSMetaObjects")
+
+	if opts.LogDetail == nil {
+		opts.LogDetail = log.Debug
+	}
+
+	if !setting.LFS.StartServer {
+		opts.LogDetail("LFS support is disabled")
+		return nil
+	}
+
+	return git_model.IterateRepositoryIDsWithLFSMetaObjects(ctx, func(ctx context.Context, repoID, count int64) error {
+		repo, err := repo_model.GetRepositoryByID(ctx, repoID)
+		if err != nil {
+			return err
+		}
+
+		return GarbageCollectLFSMetaObjectsForRepo(ctx, repo, opts)
+	})
+}
+
+// GarbageCollectLFSMetaObjectsForRepo garbage collects LFS objects for a specific repository
+func GarbageCollectLFSMetaObjectsForRepo(ctx context.Context, repo *repo_model.Repository, opts GarbageCollectLFSMetaObjectsOptions) error {
+	opts.LogDetail("Checking %s", repo.FullName())
+	total, orphaned, collected, deleted := int64(0), 0, 0, 0
+	defer func() {
+		if orphaned == 0 {
+			opts.LogDetail("Found %d total LFSMetaObjects in %s", total, repo.FullName())
+		} else if !opts.AutoFix {
+			opts.LogDetail("Found %d/%d orphaned LFSMetaObjects in %s", orphaned, total, repo.FullName())
+		} else {
+			opts.LogDetail("Collected %d/%d orphaned/%d total LFSMetaObjects in %s. %d removed from storage.", collected, orphaned, total, repo.FullName(), deleted)
+		}
+	}()
+
+	gitRepo, err := gitrepo.OpenRepository(ctx, repo)
+	if err != nil {
+		log.Error("Unable to open git repository %s: %v", repo.FullName(), err)
+		return err
+	}
+	defer gitRepo.Close()
+
+	store := lfs.NewContentStore()
+	objectFormat := git.ObjectFormatFromName(repo.ObjectFormatName)
+
+	err = git_model.IterateLFSMetaObjectsForRepo(ctx, repo.ID, func(ctx context.Context, metaObject *git_model.LFSMetaObject) error {
+		total++
+		pointerSha := git.ComputeBlobHash(objectFormat, []byte(metaObject.Pointer.StringContent()))
+
+		if gitRepo.IsObjectExist(pointerSha.String()) {
+			return git_model.MarkLFSMetaObject(ctx, metaObject.ID)
+		}
+		orphaned++
+
+		if !opts.AutoFix {
+			return nil
+		}
+		// Non-existent pointer file
+		_, err = git_model.RemoveLFSMetaObjectByOidFn(ctx, repo.ID, metaObject.Oid, func(count int64) error {
+			if count > 0 {
+				return nil
+			}
+
+			if err := store.Delete(metaObject.RelativePath()); err != nil {
+				log.Error("Unable to remove lfs metaobject %s from store: %v", metaObject.Oid, err)
+			}
+			deleted++
+			return nil
+		})
+		if err != nil {
+			return fmt.Errorf("unable to remove meta-object %s in %s: %w", metaObject.Oid, repo.FullName(), err)
+		}
+		collected++
+
+		return nil
+	}, &git_model.IterateLFSMetaObjectsForRepoOptions{
+		// Only attempt to garbage collect lfs meta objects older than a week as the order of git lfs upload
+		// and git object upload is not necessarily guaranteed. It's possible to imagine a situation whereby
+		// an LFS object is uploaded but the git branch is not uploaded immediately, or there are some rapid
+		// changes in new branches that might lead to lfs objects becoming temporarily unassociated with git
+		// objects.
+		//
+		// It is likely that a week is potentially excessive but it should definitely be enough that any
+		// unassociated LFS object is genuinely unassociated.
+		OlderThan:               timeutil.TimeStamp(opts.OlderThan.Unix()),
+		UpdatedLessRecentlyThan: timeutil.TimeStamp(opts.UpdatedLessRecentlyThan.Unix()),
+	})
+	if err != nil {
+		return err
+	}
+	return nil
+}