Method Describe

pkg/blobmanager/oci/backend.go:168–206

(_ context.Context, digest string)

}

func (b *Backend) Describe(_ context.Context, digest string) (*pb.CASResource, error) {
	if digest == "" {
		return nil, errors.New("digest is empty")
	}

	ref, err := name.ParseReference(b.resourcePath(digest))
	if err != nil {
		return nil, fmt.Errorf("parsing reference: %w", err)
	}

	img, err := remote.Image(ref, remote.WithAuthFromKeychain(b.keychain))
	if err != nil {
		var e *transport.Error
		if errors.As(err, &e) && e.StatusCode == http.StatusNotFound {
			return nil, backend.NewErrNotFound("image")
		}

		return nil, fmt.Errorf("getting image: %w", err)
	}

	if err := validateImage(img, digest); err != nil {
		return nil, fmt.Errorf("validating image: %w", err)
	}

	manifest, err := img.Manifest()
	if err != nil {
		return nil, fmt.Errorf("extracting manifest: %w", err)
	}

	// Validate image already checked that the manifest has exactly one layer
	size := manifest.Layers[0].Size

	filename, ok := manifest.Annotations[ocispec.AnnotationTitle]
	if !ok {
		return nil, errors.New("couldn't find file metadata")
	}

	return &pb.CASResource{Digest: digest, FileName: filename, Size: size}, nil
}

func (b *Backend) Download(_ context.Context, w io.Writer, digest string) error {
	if digest == "" {