Merge pull request #1630 from vrothberg/oci-ref

libimage: preserve optional name when pulling from OCI transport

libimage/pull.go

@@ -230,8 +230,18 @@ func (r *Runtime) copyFromDefault(ctx context.Context, ref types.ImageReference,
 
 	case ociTransport.Transport.Name():
 		split := strings.SplitN(ref.StringWithinTransport(), ":", 2)
-		storageName = toLocalImageName(split[0])
-		imageName = storageName
+		if len(split) == 1 || split[1] == "" {
+			// Same trick as for the dir transport: we cannot use
+			// the path to a directory as the name.
+			storageName, err = getImageID(ctx, ref, nil)
+			if err != nil {
+				return nil, err
+			}
+			imageName = "sha256:" + storageName[1:]
+		} else { // If the OCI-reference includes an image reference, use it
+			storageName = split[1]
+			imageName = storageName
+		}
 
 	case ociArchiveTransport.Transport.Name():
 		manifestDescriptor, err := ociArchiveTransport.LoadManifestDescriptorWithContext(r.SystemContext(), ref)

libimage/pull_test.go

@@ -220,3 +220,52 @@ func TestShortNameAndIDconflict(t *testing.T) {
 	require.NoError(t, err)
 	require.Equal(t, busybox[0].ID(), img.ID())
 }
+
+func TestPullOCINoReference(t *testing.T) {
+	// Exercise pulling from the OCI transport and make sure that a
+	// specified reference is preserved in the image name.
+
+	busybox := "docker.io/library/busybox:latest"
+	runtime, cleanup := testNewRuntime(t)
+	defer cleanup()
+	ctx := context.Background()
+	pullOptions := &PullOptions{}
+	pullOptions.Writer = os.Stdout
+
+	images, err := runtime.Pull(ctx, busybox, config.PullPolicyAlways, pullOptions)
+	require.NoError(t, err)
+	require.Len(t, images, 1)
+
+	// Push one image without the optional reference
+	ociPathNoRef := "oci:" + t.TempDir() + "noRef"
+	_, err = runtime.Push(ctx, busybox, ociPathNoRef, nil)
+	require.NoError(t, err)
+
+	// Push another image _with_ the optional reference which allows for
+	// preserving the name.
+	ociPathWithRef := "oci:" + t.TempDir() + "withRef:" + busybox
+	_, err = runtime.Push(ctx, busybox, ociPathWithRef, nil)
+	require.NoError(t, err)
+
+	_, errors := runtime.RemoveImages(ctx, []string{busybox}, nil)
+	require.Nil(t, errors)
+
+	images, err = runtime.Pull(ctx, ociPathNoRef, config.PullPolicyAlways, pullOptions)
+	require.NoError(t, err)
+	require.Len(t, images, 1)
+
+	exists, err := runtime.Exists(busybox) // busybox does not exist
+	require.NoError(t, err)
+	require.False(t, exists)
+
+	names := images[0].Names() // The image has no names (i.e., <none>)
+	require.Nil(t, names)
+
+	images, err = runtime.Pull(ctx, ociPathWithRef, config.PullPolicyAlways, pullOptions)
+	require.NoError(t, err)
+	require.Len(t, images, 1)
+
+	exists, err = runtime.Exists(busybox) // busybox does exist now
+	require.NoError(t, err)
+	require.True(t, exists)
+}