fix: force config media type when setting platform (#1519)

Signed-off-by: Billy Zha <[email protected]>
Co-authored-by: Terry Howe <[email protected]>

cmd/oras/root/push.go

@@ -197,11 +197,13 @@ func runPush(cmd *cobra.Command, opts *pushOptions) error {
 		if err != nil {
 			return err
 		}
-		mediaType := ocispec.MediaTypeImageConfig
 		if opts.Flag == option.ImageSpecV1_0 && opts.artifactType != "" {
-			mediaType = opts.artifactType
+			return &oerrors.Error{
+				Err:            errors.New(`artifact type cannot be customized for OCI image-spec v1.0 when platform is specified`),
+				Recommendation: "consider using image spec v1.1 or remove --artifact-type",
+			}
 		}
-		desc := content.NewDescriptorFromBytes(mediaType, blob)
+		desc := content.NewDescriptorFromBytes(ocispec.MediaTypeImageConfig, blob)
 		err = store.Push(ctx, desc, bytes.NewReader(blob))
 		if err != nil {
 			return err

test/e2e/suite/command/push.go

@@ -640,24 +640,12 @@ var _ = Describe("OCI image layout users:", func() {
 			}))
 		})
 
-		It("should push files with platform with mediaType as artifactType for v1.0", func() {
+		It("should fail to customize config mediaType when baking config blob with platform for v1.0", func() {
 			tempDir := PrepareTempFiles()
 			ref := LayoutRef(tempDir, tag)
 			ORAS("push", Flags.Layout, ref, "--image-spec", "v1.0", "--artifact-type", "test/artifact+json", "--artifact-platform", "darwin/arm64", foobar.FileBarName, "-v").
-				MatchStatus([]match.StateKey{
-					foobar.PlatformV10ConfigStateKey,
-					foobar.FileBarStateKey,
-				}, true, 2).
-				WithWorkDir(tempDir).Exec()
-			// validate
-			fetched := ORAS("manifest", "fetch", Flags.Layout, ref).Exec().Out.Contents()
-			var manifest ocispec.Manifest
-			Expect(json.Unmarshal(fetched, &manifest)).ShouldNot(HaveOccurred())
-			Expect(manifest.Config).Should(Equal(ocispec.Descriptor{
-				MediaType: "test/artifact+json",
-				Size:      int64(foobar.PlatformV10ConfigSize),
-				Digest:    foobar.PlatformV10ConfigDigest,
-			}))
+				ExpectFailure().
+				Exec()
 		})
 
 		It("should push files with platform with no artifactType for v1.0", func() {