fix(gc): gc now removes blob uploads which have not changed within the gc delay interval

pkg/storage/gc/gc.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"math/rand"
 	"path"
+	"strconv"
 	"strings"
 	"time"
 
@@ -149,6 +150,11 @@ func (gc GarbageCollect) cleanRepo(ctx context.Context, repo string) error {
 		return err
 	}
 
+	// gc old blob uploads
+	if err := gc.removeBlobUploads(repo, gc.opts.Delay); err != nil {
+		return err
+	}
+
 	return nil
 }
 
@@ -546,6 +552,52 @@ func (gc GarbageCollect) identifyManifestsReferencedInIndex(index ispec.Index, r
 	return nil
 }
 
+// removeBlobUploads gc all temporary uploads which are past their gc delay.
+func (gc GarbageCollect) removeBlobUploads(repo string, delay time.Duration) error {
+	gc.log.Debug().Str("module", "gc").Str("repository", repo).Msg("cleaning unclaimed blob uploads")
+
+	if dir := path.Join(gc.imgStore.RootDir(), repo); !gc.imgStore.DirExists(dir) {
+		// The repository was already cleaned up by a different codepath
+		return nil
+	}
+
+	blobUploads, err := gc.imgStore.ListBlobUploads(repo)
+	if err != nil {
+		gc.log.Error().Err(err).Str("module", "gc").Str("repository", repo).Msg("failed to get list of blob uploads")
+
+		return err
+	}
+
+	var aggregatedErr error
+
+	for _, uuid := range blobUploads {
+		_, size, modtime, err := gc.imgStore.StatBlobUpload(repo, uuid)
+		if err != nil {
+			gc.log.Error().Err(err).Str("module", "gc").Str("repository", repo).Str("blobUpload", uuid).
+				Msg("failed to stat blob upload")
+
+			aggregatedErr = errors.Join(aggregatedErr, err)
+
+			continue
+		}
+
+		if modtime.Add(delay).After(time.Now()) {
+			// Do not delete blob uploads which have been updated recently
+			continue
+		}
+
+		err = gc.imgStore.DeleteBlobUpload(repo, uuid)
+		if err != nil {
+			gc.log.Error().Err(err).Str("module", "gc").Str("repository", repo).Str("blobUpload", uuid).
+				Str("size", strconv.FormatInt(size, 10)).Str("modified", modtime.String()).Msg("failed to delete blob upload")
+
+			aggregatedErr = errors.Join(aggregatedErr, err)
+		}
+	}
+
+	return aggregatedErr
+}
+
 // removeUnreferencedBlobs gc all blobs which are not referenced by any manifest found in repo's index.json.
 func (gc GarbageCollect) removeUnreferencedBlobs(repo string, delay time.Duration, log zlog.Logger,
 ) error {

pkg/storage/gc/gc_test.go

@@ -1,6 +1,7 @@
 package gc_test
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"os"
@@ -32,7 +33,9 @@ import (
 )
 
 const (
-	region = "us-east-2"
+	region        = "us-east-2"
+	s3TestName    = "S3APIs"
+	localTestName = "LocalAPIs"
 )
 
 //nolint:gochecknoglobals
@@ -41,17 +44,17 @@ var testCases = []struct {
 	storageType  string
 }{
 	{
-		testCaseName: "S3APIs",
+		testCaseName: s3TestName,
 		storageType:  storageConstants.S3StorageDriverName,
 	},
 	{
-		testCaseName: "LocalAPIs",
+		testCaseName: localTestName,
 		storageType:  storageConstants.LocalStorageDriverName,
 	},
 }
 
 func TestGarbageCollectAndRetention(t *testing.T) {
-	log := zlog.NewLogger("info", "/dev/null")
+	log := zlog.NewLogger("debug", "")
 	audit := zlog.NewAuditLogger("debug", "/dev/null")
 
 	metrics := monitoring.NewMetricsServer(false, log)
@@ -887,6 +890,105 @@ func TestGarbageCollectAndRetention(t *testing.T) {
 					err := gc.CleanRepo(ctx, "gc-test1")
 					So(err, ShouldNotBeNil)
 				})
+
+				Convey("should gc only stale blob uploads", func() {
+					gcDelay := 1 * time.Second
+					repoName := "gc-test1"
+
+					gc := gc.NewGarbageCollect(imgStore, metaDB, gc.Options{
+						Delay: gcDelay,
+						ImageRetention: config.ImageRetention{
+							Delay: storageConstants.DefaultRetentionDelay,
+							Policies: []config.RetentionPolicy{
+								{
+									Repositories:    []string{"**"},
+									DeleteReferrers: true,
+									DeleteUntagged:  &trueVal,
+									KeepTags: []config.KeepTagsPolicy{
+										{},
+									},
+								},
+							},
+						},
+					}, audit, log)
+
+					blobUploadID, err := imgStore.NewBlobUpload(repoName)
+					So(err, ShouldBeNil)
+
+					content := []byte("test-data3")
+					buf := bytes.NewBuffer(content)
+					_, err = imgStore.PutBlobChunkStreamed(repoName, blobUploadID, buf)
+					So(err, ShouldBeNil)
+
+					// Blob upload should be there
+					uploads, err := imgStore.ListBlobUploads(repoName)
+					So(err, ShouldBeNil)
+
+					if testcase.testCaseName == s3TestName {
+						// Remote sorage is written to only after the blob upload is finished,
+						// there should be no space used by blob uploads
+						So(uploads, ShouldEqual, []string{})
+					} else {
+						// Local storage is used right away
+						So(uploads, ShouldEqual, []string{blobUploadID})
+					}
+
+					isPresent, _, _, err := imgStore.StatBlobUpload(repoName, blobUploadID)
+
+					if testcase.testCaseName == s3TestName {
+						// Remote sorage is written to only after the blob upload is finished,
+						// there should be no space used by blob uploads
+						So(err, ShouldNotBeNil)
+						So(isPresent, ShouldBeFalse)
+					} else {
+						// Local storage is used right away
+						So(err, ShouldBeNil)
+						So(isPresent, ShouldBeTrue)
+					}
+
+					err = gc.CleanRepo(ctx, repoName)
+					So(err, ShouldBeNil)
+
+					// Blob upload is recent it should still be there
+					uploads, err = imgStore.ListBlobUploads(repoName)
+					So(err, ShouldBeNil)
+
+					if testcase.testCaseName == s3TestName {
+						// Remote sorage is written to only after the blob upload is finished,
+						// there should be no space used by blob uploads
+						So(uploads, ShouldEqual, []string{})
+					} else {
+						// Local storage is used right away
+						So(uploads, ShouldEqual, []string{blobUploadID})
+					}
+
+					isPresent, _, _, err = imgStore.StatBlobUpload(repoName, blobUploadID)
+
+					if testcase.testCaseName == s3TestName {
+						// Remote sorage is written to only after the blob upload is finished,
+						// there should be no space used by blob uploads
+						So(err, ShouldNotBeNil)
+						So(isPresent, ShouldBeFalse)
+					} else {
+						// Local storage is used right away
+						So(err, ShouldBeNil)
+						So(isPresent, ShouldBeTrue)
+					}
+
+					time.Sleep(gcDelay + 1*time.Second)
+
+					err = gc.CleanRepo(ctx, repoName)
+					So(err, ShouldBeNil)
+
+					// Blob uploads should be GCed
+					uploads, err = imgStore.ListBlobUploads(repoName)
+					So(err, ShouldBeNil)
+					So(uploads, ShouldBeEmpty)
+
+					isPresent, _, _, err = imgStore.StatBlobUpload(repoName, blobUploadID)
+					So(err, ShouldNotBeNil)
+					So(isPresent, ShouldBeFalse)
+				})
 			})
 		})
 	}

pkg/storage/imagestore/imagestore.go

@@ -691,6 +691,42 @@ func (is *ImageStore) BlobUploadPath(repo, uuid string) string {
 	return blobUploadPath
 }
 
+/*
+ListBlobUploads returns all blob uploads present in the repository. The caller function MUST lock from outside.
+*/
+func (is *ImageStore) ListBlobUploads(repo string) ([]string, error) {
+	blobUploadPaths, err := is.storeDriver.List(path.Join(is.RootDir(), repo, storageConstants.BlobUploadDir))
+	if err != nil {
+		if errors.As(err, &driver.PathNotFoundError{}) {
+			// blobs uploads folder does not exist
+			return []string{}, nil
+		}
+
+		is.log.Debug().Str("repository", repo).Msg("failed to list .uploads/ dir")
+	}
+
+	blobUploads := []string{}
+	for _, blobUploadPath := range blobUploadPaths {
+		blobUploads = append(blobUploads, path.Base(blobUploadPath))
+	}
+
+	return blobUploads, err
+}
+
+// StatBlobUpload verifies if a blob upload is present inside a repository. The caller function MUST lock from outside.
+func (is *ImageStore) StatBlobUpload(repo, uuid string) (bool, int64, time.Time, error) {
+	blobUploadPath := is.BlobUploadPath(repo, uuid)
+
+	binfo, err := is.storeDriver.Stat(blobUploadPath)
+	if err != nil {
+		is.log.Error().Err(err).Str("blobUpload", blobUploadPath).Msg("failed to stat blob upload")
+
+		return false, -1, time.Time{}, err
+	}
+
+	return true, binfo.Size(), binfo.ModTime(), nil
+}
+
 // NewBlobUpload returns the unique ID for an upload in progress.
 func (is *ImageStore) NewBlobUpload(repo string) (string, error) {
 	if err := is.InitRepo(repo); err != nil {
@@ -1572,10 +1608,7 @@ func (is *ImageStore) CleanupRepo(repo string, blobs []godigest.Digest, removeRe
 		}
 	}
 
-	blobUploads, err := is.storeDriver.List(path.Join(is.RootDir(), repo, storageConstants.BlobUploadDir))
-	if err != nil {
-		is.log.Debug().Str("repository", repo).Msg("failed to list .uploads/ dir")
-	}
+	blobUploads, _ := is.ListBlobUploads(repo)
 
 	// if removeRepo flag is true and we cleanup all blobs and there are no blobs currently being uploaded.
 	if removeRepo && count == len(blobs) && count > 0 && len(blobUploads) == 0 {

pkg/storage/local/local_test.go

@@ -1970,7 +1970,7 @@ func TestGarbageCollectForImageStore(t *testing.T) {
 			}, log)
 
 			imgStore := local.NewImageStore(dir, true, true, log, metrics, nil, cacheDriver)
-			repoName := "gc-all-repos-short"
+			repoName := "gc-all-repos-short" //nolint:goconst // test data
 
 			gc := gc.NewGarbageCollect(imgStore, mocks.MetaDBMock{}, gc.Options{
 				Delay:          1 * time.Second,
@@ -2046,11 +2046,7 @@ func TestGarbageCollectForImageStore(t *testing.T) {
 		})
 
 		Convey("Garbage collect - the manifest which the reference points to can be found", func() {
-			logFile, _ := os.CreateTemp("", "zot-log*.txt")
-
-			defer os.Remove(logFile.Name()) // clean up
-
-			log := zlog.NewLogger("debug", logFile.Name())
+			log := zlog.NewLogger("debug", "")
 			audit := zlog.NewAuditLogger("debug", "")
 
 			metrics := monitoring.NewMetricsServer(false, log)
@@ -2121,6 +2117,78 @@ func TestGarbageCollectForImageStore(t *testing.T) {
 			err = gc.CleanRepo(ctx, repoName)
 			So(err, ShouldBeNil)
 		})
+
+		Convey("Garbage collect error - not enough permissions to access blob upload", func() {
+			logFile, _ := os.CreateTemp("", "zot-log*.txt")
+
+			defer os.Remove(logFile.Name()) // clean up
+
+			log := zlog.NewLogger("debug", logFile.Name())
+			audit := zlog.NewAuditLogger("debug", "")
+
+			metrics := monitoring.NewMetricsServer(false, log)
+			cacheDriver, _ := storage.Create("boltdb", cache.BoltDBDriverParameters{
+				RootDir:     dir,
+				Name:        "cache",
+				UseRelPaths: true,
+			}, log)
+
+			imgStore := local.NewImageStore(dir, true, true, log, metrics, nil, cacheDriver)
+			repoName := "gc-all-repos-short"
+
+			gc := gc.NewGarbageCollect(imgStore, mocks.MetaDBMock{}, gc.Options{
+				Delay:          1 * time.Second,
+				ImageRetention: DeleteReferrers,
+			}, audit, log)
+
+			blobUploadID, err := imgStore.NewBlobUpload(repoName)
+			So(err, ShouldBeNil)
+
+			err = gc.CleanRepo(ctx, repoName)
+			So(err, ShouldBeNil)
+
+			// Blob upload is recent it should still be there
+			isPresent, _, _, err := imgStore.StatBlobUpload(repoName, blobUploadID)
+			So(err, ShouldBeNil)
+			So(isPresent, ShouldBeTrue)
+
+			So(os.Chmod(imgStore.BlobUploadPath(repoName, blobUploadID), 0o000), ShouldBeNil)
+
+			err = gc.CleanRepo(ctx, repoName)
+			So(err, ShouldBeNil)
+
+			// Blob upload is recent it should still be there
+			isPresent, _, _, err = imgStore.StatBlobUpload(repoName, blobUploadID)
+			So(err, ShouldBeNil)
+			So(isPresent, ShouldBeTrue)
+
+			time.Sleep(1002 * time.Millisecond)
+
+			// GC should fail because of bad permissions
+			err = gc.CleanRepo(ctx, repoName)
+			So(err, ShouldNotBeNil)
+
+			// Blob uploads should not be GCed as there was an error
+			isPresent, _, _, err = imgStore.StatBlobUpload(repoName, blobUploadID)
+			So(err, ShouldBeNil)
+			So(isPresent, ShouldBeTrue)
+
+			So(os.Chmod(imgStore.BlobUploadPath(repoName, blobUploadID), 0o777), ShouldBeNil)
+
+			// GC should no longer error
+			err = gc.CleanRepo(ctx, repoName)
+			So(err, ShouldBeNil)
+
+			// Blob uploads should have correctly been GCed
+			isPresent, _, _, err = imgStore.StatBlobUpload(repoName, blobUploadID)
+			So(err, ShouldNotBeNil)
+			So(isPresent, ShouldBeFalse)
+
+			data, err := os.ReadFile(logFile.Name())
+			So(err, ShouldBeNil)
+			So(string(data), ShouldContainSubstring,
+				"failed to run GC for "+path.Join(imgStore.RootDir(), repoName))
+		})
 	})
 }
 

pkg/storage/types/types.go

@@ -35,6 +35,8 @@ type ImageStore interface { //nolint:interfacebloat
 	PutImageManifest(repo, reference, mediaType string, body []byte) (godigest.Digest, godigest.Digest, error)
 	DeleteImageManifest(repo, reference string, detectCollision bool) error
 	BlobUploadPath(repo, uuid string) string
+	StatBlobUpload(repo, uuid string) (bool, int64, time.Time, error)
+	ListBlobUploads(repo string) ([]string, error)
 	NewBlobUpload(repo string) (string, error)
 	GetBlobUpload(repo, uuid string) (int64, error)
 	PutBlobChunkStreamed(repo, uuid string, body io.Reader) (int64, error)