Function MakeRefKey

core/remotes/handlers.go:79–113

MakeRefKey returns a stable ingest reference for desc. The returned key is used as a content-store reference to correlate ongoing fetch and push operations for the same descriptor. The key is derived from the descriptor digest and, when present, the [ocispec.AnnotationRefName] annotation. By defau

(ctx context.Context, desc ocispec.Descriptor)

// If the media type is not recognized and no context override exists,
// MakeRefKey falls back to the "unknown-" prefix.
func MakeRefKey(ctx context.Context, desc ocispec.Descriptor) string {
	key := desc.Digest.String()
	if desc.Annotations != nil {
		if name, ok := desc.Annotations[ocispec.AnnotationRefName]; ok {
			key = fmt.Sprintf("%s@%s", name, desc.Digest.String())
		}
	}

	if v := ctx.Value(refKeyPrefix{}); v != nil {
		values := v.(map[string]string)
		if prefix := values[desc.MediaType]; prefix != "" {
			return prefix + "-" + key
		}
	}

	switch {
	case images.IsManifestType(desc.MediaType):
		return "manifest-" + key
	case images.IsIndexType(desc.MediaType):
		return "index-" + key
	case images.IsLayerType(desc.MediaType):
		return "layer-" + key
	case images.IsKnownConfig(desc.MediaType):
		return "config-" + key
	case images.IsAttestationType(desc.MediaType):
		return "attestation-" + key
	default:
		log.G(ctx).WithFields(log.Fields{
			"digest":       desc.Digest,
			"mediatype":    desc.MediaType,
			"artifactType": desc.ArtifactType,
		}).Debug("using generic reference key prefix for unclassified descriptor")
		return "unknown-" + key
	}
}

// FetchHandler returns a handler that will fetch all content into the ingester
// discovered in a call to Dispatch. Use with ChildrenHandler to do a full