feat: support nydus image format

image/internal/image/oci.go

@@ -290,6 +290,8 @@ func (m *manifestOCI1) convertToManifestSchema2(_ context.Context, options *type
 		case ociencspec.MediaTypeLayerEnc, ociencspec.MediaTypeLayerGzipEnc, ociencspec.MediaTypeLayerZstdEnc,
 			ociencspec.MediaTypeLayerNonDistributableEnc, ociencspec.MediaTypeLayerNonDistributableGzipEnc, ociencspec.MediaTypeLayerNonDistributableZstdEnc:
 			return nil, fmt.Errorf("during manifest conversion: encrypted layers (%q) are not supported in docker images", layers[idx].MediaType)
+		case internalManifest.NydusBootstrapLayerMediaType, internalManifest.NydusBlobLayerMediaType:
+			return nil, fmt.Errorf("during manifest conversion: Nydus layers (%q) are not supported in docker images", layers[idx].MediaType)
 		default:
 			return nil, fmt.Errorf("Unknown media type during manifest conversion: %q", layers[idx].MediaType)
 		}

image/internal/image/oci_test.go

@@ -17,6 +17,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.podman.io/image/v5/docker/reference"
+	internalManifest "go.podman.io/image/v5/internal/manifest"
 	"go.podman.io/image/v5/internal/testing/mocks"
 	"go.podman.io/image/v5/manifest"
 	"go.podman.io/image/v5/pkg/compression"
@@ -884,8 +885,9 @@ func TestManifestOCI1CanChangeLayerCompression(t *testing.T) {
 		manifestOCI1FromComponentsLikeFixture(nil),
 	} {
 		assert.True(t, m.CanChangeLayerCompression(imgspecv1.MediaTypeImageLayerGzip))
-		// Some projects like to use squashfs and other unspecified formats for layers; don’t touch those.
 		assert.False(t, m.CanChangeLayerCompression("a completely unknown and quite possibly invalid MIME type"))
+		assert.False(t, m.CanChangeLayerCompression(internalManifest.NydusBootstrapLayerMediaType))
+		assert.False(t, m.CanChangeLayerCompression(internalManifest.NydusBlobLayerMediaType))
 	}
 
 	artifact := manifestOCI1FromFixture(t, mocks.ForbiddenImageSource{}, "oci1-artifact.json")

image/internal/manifest/manifest.go

@@ -34,6 +34,10 @@ const (
 	DockerV2Schema2ForeignLayerMediaType = "application/vnd.docker.image.rootfs.foreign.diff.tar"
 	// DockerV2Schema2ForeignLayerMediaType is the MIME type used for gzipped schema 2 foreign layers.
 	DockerV2Schema2ForeignLayerMediaTypeGzip = "application/vnd.docker.image.rootfs.foreign.diff.tar.gzip"
+	// NydusBootstrapLayerMediaType is the MIME type used for Nydus bootstrap layers.
+	NydusBootstrapLayerMediaType = "application/vnd.containers.image.nydus.bootstrap.v1+json"
+	// NydusBlobLayerMediaType is the MIME type used for Nydus data blob layers.
+	NydusBlobLayerMediaType = "application/vnd.containers.image.nydus.blob.v1"
 )
 
 // GuessMIMEType guesses MIME type of a manifest and returns it _if it is recognized_, or "" if unknown or unrecognized.

image/manifest/oci.go

@@ -47,7 +47,8 @@ func SupportedOCI1MediaType(m string) error {
 		imgspecv1.MediaTypeImageLayerNonDistributable, imgspecv1.MediaTypeImageLayerNonDistributableGzip, imgspecv1.MediaTypeImageLayerNonDistributableZstd, //nolint:staticcheck // NonDistributable layers are deprecated, but we want to continue to support manipulating pre-existing images.
 		imgspecv1.MediaTypeImageManifest,
 		imgspecv1.MediaTypeLayoutHeader,
-		ociencspec.MediaTypeLayerEnc, ociencspec.MediaTypeLayerGzipEnc:
+		ociencspec.MediaTypeLayerEnc, ociencspec.MediaTypeLayerGzipEnc,
+		manifest.NydusBootstrapLayerMediaType, manifest.NydusBlobLayerMediaType:
 		return nil
 	default:
 		return fmt.Errorf("unsupported OCIv1 media type: %q", m)
@@ -142,10 +143,13 @@ func (m *OCI1) UpdateLayerInfos(layerInfos []types.BlobInfo) error {
 			}
 			mimeType = decMimeType
 		}
-		mimeType, err := updatedMIMEType(oci1CompressionMIMETypeSets, mimeType, info)
+
+		var err error
+		mimeType, err = updatedMIMEType(oci1CompressionMIMETypeSets, mimeType, info)
 		if err != nil {
 			return fmt.Errorf("preparing updated manifest, layer %q: %w", info.Digest, err)
 		}
+
 		if info.CryptoOperation == types.Encrypt {
 			encMediaType, err := getEncryptedMediaType(mimeType)
 			if err != nil {

image/manifest/oci_test.go

@@ -9,6 +9,7 @@ import (
 	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	internalManifest "go.podman.io/image/v5/internal/manifest"
 	"go.podman.io/image/v5/pkg/compression"
 	"go.podman.io/image/v5/types"
 )
@@ -405,9 +406,13 @@ func TestOCI1CanChangeLayerCompression(t *testing.T) {
 	m := manifestOCI1FromFixture(t, "ociv1.manifest.json")
 
 	assert.True(t, m.CanChangeLayerCompression(imgspecv1.MediaTypeImageLayerGzip))
-	// Some projects like to use squashfs and other unspecified formats for layers; don’t touch those.
+	// Some projects like to use squashfs and other unspecified formats for layers; don't touch those.
 	assert.False(t, m.CanChangeLayerCompression("a completely unknown and quite possibly invalid MIME type"))
 
 	artifact := manifestOCI1FromFixture(t, "ociv1.artifact.json")
 	assert.False(t, artifact.CanChangeLayerCompression(imgspecv1.MediaTypeImageLayerGzip))
+
+	// Nydus layer types don't support compression changes
+	assert.False(t, m.CanChangeLayerCompression(internalManifest.NydusBootstrapLayerMediaType))
+	assert.False(t, m.CanChangeLayerCompression(internalManifest.NydusBlobLayerMediaType))
 }