Merge pull request #305 from nalind/storage-update

Rework how we use containers/storage

copy/copy.go

@@ -368,6 +368,15 @@ func (ic *imageCopier) copyLayers() error {
 	srcInfos := ic.src.LayerInfos()
 	destInfos := []types.BlobInfo{}
 	diffIDs := []digest.Digest{}
+	updatedSrcInfos := ic.src.LayerInfosForCopy()
+	srcInfosUpdated := false
+	if updatedSrcInfos != nil && !reflect.DeepEqual(srcInfos, updatedSrcInfos) {
+		if !ic.canModifyManifest {
+			return errors.Errorf("Internal error: copyLayers() needs to use an updated manifest but that was known to be forbidden")
+		}
+		srcInfos = updatedSrcInfos
+		srcInfosUpdated = true
+	}
 	for _, srcLayer := range srcInfos {
 		var (
 			destInfo types.BlobInfo
@@ -396,7 +405,7 @@ func (ic *imageCopier) copyLayers() error {
 	if ic.diffIDsAreNeeded {
 		ic.manifestUpdates.InformationOnly.LayerDiffIDs = diffIDs
 	}
-	if layerDigestsDiffer(srcInfos, destInfos) {
+	if srcInfosUpdated || layerDigestsDiffer(srcInfos, destInfos) {
 		ic.manifestUpdates.LayerInfos = destInfos
 	}
 	return nil

copy/manifest_test.go

@@ -56,6 +56,9 @@ func (f fakeImageSource) OCIConfig() (*v1.Image, error) {
 func (f fakeImageSource) LayerInfos() []types.BlobInfo {
 	panic("Unexpected call to a mock function")
 }
+func (f fakeImageSource) LayerInfosForCopy() []types.BlobInfo {
+	panic("Unexpected call to a mock function")
+}
 func (f fakeImageSource) EmbeddedDockerReferenceConflicts(ref reference.Named) bool {
 	panic("Unexpected call to a mock function")
 }

directory/directory_src.go

@@ -82,3 +82,8 @@ func (s *dirImageSource) GetSignatures(ctx context.Context, instanceDigest *dige
 	}
 	return signatures, nil
 }
+
+// LayerInfosForCopy() returns updated layer info that should be used when copying, in preference to values in the manifest, if specified.
+func (s *dirImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}

docker/archive/src.go

@@ -34,3 +34,8 @@ func (s *archiveImageSource) Reference() types.ImageReference {
 func (s *archiveImageSource) Close() error {
 	return nil
 }
+
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *archiveImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}

docker/daemon/daemon_src.go

@@ -81,3 +81,8 @@ func (s *daemonImageSource) Reference() types.ImageReference {
 func (s *daemonImageSource) Close() error {
 	return os.Remove(s.tarCopyPath)
 }
+
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *daemonImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}

docker/docker_image_src.go

@@ -52,6 +52,11 @@ func (s *dockerImageSource) Close() error {
 	return nil
 }
 
+// LayerInfosForCopy() returns updated layer info that should be used when reading, in preference to values in the manifest, if specified.
+func (s *dockerImageSource) LayerInfosForCopy() []types.BlobInfo {
+	return nil
+}
+
 // simplifyContentType drops parameters from a HTTP media type (see https://tools.ietf.org/html/rfc7231#section-3.1.1.1)
 // Alternatively, an empty string is returned unchanged, and invalid values are "simplified" to an empty string.
 func simplifyContentType(contentType string) string {

docker/tarfile/dest.go

@@ -167,7 +167,7 @@ func (d *Destination) ReapplyBlob(info types.BlobInfo) (types.BlobInfo, error) {
 func (d *Destination) PutManifest(m []byte) error {
 	// We do not bother with types.ManifestTypeRejectedError; our .SupportedManifestMIMETypes() above is already providing only one alternative,
 	// so the caller trying a different manifest kind would be pointless.
-	var man schema2Manifest
+	var man manifest.Schema2
 	if err := json.Unmarshal(m, &man); err != nil {
 		return errors.Wrap(err, "Error parsing manifest")
 	}
@@ -176,12 +176,12 @@ func (d *Destination) PutManifest(m []byte) error {
 	}
 
 	layerPaths := []string{}
-	for _, l := range man.Layers {
+	for _, l := range man.LayersDescriptors {
 		layerPaths = append(layerPaths, l.Digest.String())
 	}
 
 	items := []ManifestItem{{
-		Config:       man.Config.Digest.String(),
+		Config:       man.ConfigDescriptor.Digest.String(),
 		RepoTags:     []string{d.repoTag},
 		Layers:       layerPaths,
 		Parent:       "",

docker/tarfile/src.go

@@ -24,8 +24,8 @@ type Source struct {
 	tarManifest       *ManifestItem // nil if not available yet.
 	configBytes       []byte
 	configDigest      digest.Digest
-	orderedDiffIDList []diffID
-	knownLayers       map[diffID]*layerInfo
+	orderedDiffIDList []digest.Digest
+	knownLayers       map[digest.Digest]*layerInfo
 	// Other state
 	generatedManifest []byte // Private cache for GetManifest(), nil if not set yet.
 }
@@ -156,7 +156,7 @@ func (s *Source) ensureCachedDataIsPresent() error {
 	if err != nil {
 		return err
 	}
-	var parsedConfig image // Most fields ommitted, we only care about layer DiffIDs.
+	var parsedConfig manifest.Schema2Image // There's a lot of info there, but we only really care about layer DiffIDs.
 	if err := json.Unmarshal(configBytes, &parsedConfig); err != nil {
 		return errors.Wrapf(err, "Error decoding tar config %s", tarManifest[0].Config)
 	}
@@ -194,12 +194,12 @@ func (s *Source) LoadTarManifest() ([]ManifestItem, error) {
 	return s.loadTarManifest()
 }
 
-func (s *Source) prepareLayerData(tarManifest *ManifestItem, parsedConfig *image) (map[diffID]*layerInfo, error) {
+func (s *Source) prepareLayerData(tarManifest *ManifestItem, parsedConfig *manifest.Schema2Image) (map[digest.Digest]*layerInfo, error) {
 	// Collect layer data available in manifest and config.
 	if len(tarManifest.Layers) != len(parsedConfig.RootFS.DiffIDs) {
 		return nil, errors.Errorf("Inconsistent layer count: %d in manifest, %d in config", len(tarManifest.Layers), len(parsedConfig.RootFS.DiffIDs))
 	}
-	knownLayers := map[diffID]*layerInfo{}
+	knownLayers := map[digest.Digest]*layerInfo{}
 	unknownLayerSizes := map[string]*layerInfo{} // Points into knownLayers, a "to do list" of items with unknown sizes.
 	for i, diffID := range parsedConfig.RootFS.DiffIDs {
 		if _, ok := knownLayers[diffID]; ok {
@@ -260,23 +260,23 @@ func (s *Source) GetManifest(instanceDigest *digest.Digest) ([]byte, string, err
 		if err := s.ensureCachedDataIsPresent(); err != nil {
 			return nil, "", err
 		}
-		m := schema2Manifest{
+		m := manifest.Schema2{
 			SchemaVersion: 2,
 			MediaType:     manifest.DockerV2Schema2MediaType,
-			Config: distributionDescriptor{
+			ConfigDescriptor: manifest.Schema2Descriptor{
 				MediaType: manifest.DockerV2Schema2ConfigMediaType,
 				Size:      int64(len(s.configBytes)),
 				Digest:    s.configDigest,
 			},
-			Layers: []distributionDescriptor{},
+			LayersDescriptors: []manifest.Schema2Descriptor{},
 		}
 		for _, diffID := range s.orderedDiffIDList {
 			li, ok := s.knownLayers[diffID]
 			if !ok {
 				return nil, "", errors.Errorf("Internal inconsistency: Information about layer %s missing", diffID)
 			}
-			m.Layers = append(m.Layers, distributionDescriptor{
-				Digest:    digest.Digest(diffID), // diffID is a digest of the uncompressed tarball
+			m.LayersDescriptors = append(m.LayersDescriptors, manifest.Schema2Descriptor{
+				Digest:    diffID, // diffID is a digest of the uncompressed tarball
 				MediaType: manifest.DockerV2Schema2LayerMediaType,
 				Size:      li.size,
 			})
@@ -312,7 +312,7 @@ func (s *Source) GetBlob(info types.BlobInfo) (io.ReadCloser, int64, error) {
 		return ioutil.NopCloser(bytes.NewReader(s.configBytes)), int64(len(s.configBytes)), nil
 	}
 
-	if li, ok := s.knownLayers[diffID(info.Digest)]; ok { // diffID is a digest of the uncompressed tarball,
+	if li, ok := s.knownLayers[info.Digest]; ok { // diffID is a digest of the uncompressed tarball,
 		stream, err := s.openTarComponent(li.path)
 		if err != nil {
 			return nil, 0, err

docker/tarfile/types.go

@@ -1,6 +1,9 @@
 package tarfile
 
-import "github.com/opencontainers/go-digest"
+import (
+	"github.com/containers/image/manifest"
+	"github.com/opencontainers/go-digest"
+)
 
 // Various data structures.
 
@@ -18,37 +21,8 @@ type ManifestItem struct {
 	Config       string
 	RepoTags     []string
 	Layers       []string
-	Parent       imageID                           `json:",omitempty"`
-	LayerSources map[diffID]distributionDescriptor `json:",omitempty"`
+	Parent       imageID                                      `json:",omitempty"`
+	LayerSources map[digest.Digest]manifest.Schema2Descriptor `json:",omitempty"`
 }
 
 type imageID string
-type diffID digest.Digest
-
-// Based on github.com/docker/distribution/blobs.go
-type distributionDescriptor struct {
-	MediaType string        `json:"mediaType,omitempty"`
-	Size      int64         `json:"size,omitempty"`
-	Digest    digest.Digest `json:"digest,omitempty"`
-	URLs      []string      `json:"urls,omitempty"`
-}
-
-// Based on github.com/docker/distribution/manifest/schema2/manifest.go
-// FIXME: We are repeating this all over the place; make a public copy?
-type schema2Manifest struct {
-	SchemaVersion int                      `json:"schemaVersion"`
-	MediaType     string                   `json:"mediaType,omitempty"`
-	Config        distributionDescriptor   `json:"config"`
-	Layers        []distributionDescriptor `json:"layers"`
-}
-
-// Based on github.com/docker/docker/image/image.go
-// MOST CONTENT OMITTED AS UNNECESSARY
-type image struct {
-	RootFS *rootFS `json:"rootfs,omitempty"`
-}
-
-type rootFS struct {
-	Type    string   `json:"type"`
-	DiffIDs []diffID `json:"diff_ids,omitempty"`
-}

image/docker_list.go

@@ -22,7 +22,7 @@ type platformSpec struct {
 
 // A manifestDescriptor references a platform-specific manifest.
 type manifestDescriptor struct {
-	descriptor
+	manifest.Schema2Descriptor
 	Platform platformSpec `json:"platform"`
 }