Merge pull request #1675 from mtrmac/oci-not-found

Introduce oci/{archive,layout}.ImageNotFoundError

oci/archive/oci_src.go

@@ -17,6 +17,17 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+// ImageNotFoundError is used when the OCI structure, in principle, exists and seems valid enough,
+// but nothing matches the “image” part of the provided reference.
+type ImageNotFoundError struct {
+	ref ociArchiveReference
+	// We may make members public, or add methods, in the future.
+}
+
+func (e ImageNotFoundError) Error() string {
+	return fmt.Sprintf("no descriptor found for reference %q", e.ref.image)
+}
+
 type ociArchiveImageSource struct {
 	impl.Compat
 
@@ -35,6 +46,10 @@ func newImageSource(ctx context.Context, sys *types.SystemContext, ref ociArchiv
 
 	unpackedSrc, err := tempDirRef.ociRefExtracted.NewImageSource(ctx, sys)
 	if err != nil {
+		var notFound ocilayout.ImageNotFoundError
+		if errors.As(err, &notFound) {
+			err = ImageNotFoundError{ref: ref}
+		}
 		if err := tempDirRef.deleteTempDir(); err != nil {
 			return nil, fmt.Errorf("deleting temp directory %q: %w", tempDirRef.tempDirectory, err)
 		}

oci/layout/oci_src.go

@@ -21,6 +21,17 @@ import (
 	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
 )
 
+// ImageNotFoundError is used when the OCI structure, in principle, exists and seems valid enough,
+// but nothing matches the “image” part of the provided reference.
+type ImageNotFoundError struct {
+	ref ociReference
+	// We may make members public, or add methods, in the future.
+}
+
+func (e ImageNotFoundError) Error() string {
+	return fmt.Sprintf("no descriptor found for reference %q", e.ref.image)
+}
+
 type ociImageSource struct {
 	impl.Compat
 	impl.PropertyMethodsInitialize

oci/layout/oci_transport.go

@@ -205,7 +205,7 @@ func (ref ociReference) getManifestDescriptor() (imgspecv1.Descriptor, error) {
 		}
 	}
 	if d == nil {
-		return imgspecv1.Descriptor{}, fmt.Errorf("no descriptor found for reference %q", ref.image)
+		return imgspecv1.Descriptor{}, ImageNotFoundError{ref}
 	}
 	return *d, nil
 }