From c01fe472316f3de38a95b008c93079211c91d63e Mon Sep 17 00:00:00 2001
From: Aaron Lehmann <aaron.lehmann@docker.com>
Date: Thu, 21 Jan 2016 09:34:06 -0800
Subject: [PATCH] If the media type for a manifest is unrecognized, default to
 schema1

This is needed for compatibility with some third-party registries that
send an inappropriate Content-Type header such as text/html.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
---
 manifests.go                       |  5 ++++-
 registry/client/repository_test.go | 24 +++++++++++++++++++-----
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/manifests.go b/manifests.go
index 222916b8..40f3bc75 100644
--- a/manifests.go
+++ b/manifests.go
@@ -96,7 +96,10 @@ func UnmarshalManifest(ctHeader string, p []byte) (Manifest, Descriptor, error)
 
 	unmarshalFunc, ok := mappings[mediatype]
 	if !ok {
-		return nil, Descriptor{}, fmt.Errorf("unsupported manifest mediatype: %s", mediatype)
+		unmarshalFunc, ok = mappings[""]
+		if !ok {
+			return nil, Descriptor{}, fmt.Errorf("unsupported manifest mediatype and no default available: %s", mediatype)
+		}
 	}
 
 	return unmarshalFunc(p)
diff --git a/registry/client/repository_test.go b/registry/client/repository_test.go
index 8eedc4c2..69987c87 100644
--- a/registry/client/repository_test.go
+++ b/registry/client/repository_test.go
@@ -610,7 +610,7 @@ func addTestManifestWithEtag(repo, reference string, content []byte, m *testutil
 	*m = append(*m, testutil.RequestResponseMapping{Request: getReqWithEtag, Response: getRespWithEtag})
 }
 
-func addTestManifest(repo, reference string, content []byte, m *testutil.RequestResponseMap) {
+func addTestManifest(repo, reference string, mediatype string, content []byte, m *testutil.RequestResponseMap) {
 	*m = append(*m, testutil.RequestResponseMapping{
 		Request: testutil.Request{
 			Method: "GET",
@@ -622,7 +622,7 @@ func addTestManifest(repo, reference string, content []byte, m *testutil.Request
 			Headers: http.Header(map[string][]string{
 				"Content-Length": {fmt.Sprint(len(content))},
 				"Last-Modified":  {time.Now().Add(-1 * time.Second).Format(time.ANSIC)},
-				"Content-Type":   {schema1.MediaTypeSignedManifest},
+				"Content-Type":   {mediatype},
 			}),
 		},
 	})
@@ -636,7 +636,7 @@ func addTestManifest(repo, reference string, content []byte, m *testutil.Request
 			Headers: http.Header(map[string][]string{
 				"Content-Length": {fmt.Sprint(len(content))},
 				"Last-Modified":  {time.Now().Add(-1 * time.Second).Format(time.ANSIC)},
-				"Content-Type":   {schema1.MediaTypeSignedManifest},
+				"Content-Type":   {mediatype},
 			}),
 		},
 	})
@@ -678,8 +678,9 @@ func TestV1ManifestFetch(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	addTestManifest(repo, dgst.String(), pl, &m)
-	addTestManifest(repo, "latest", pl, &m)
+	addTestManifest(repo, dgst.String(), schema1.MediaTypeSignedManifest, pl, &m)
+	addTestManifest(repo, "latest", schema1.MediaTypeSignedManifest, pl, &m)
+	addTestManifest(repo, "badcontenttype", "text/html", pl, &m)
 
 	e, c := testServer(m)
 	defer c()
@@ -726,6 +727,19 @@ func TestV1ManifestFetch(t *testing.T) {
 	if err = checkEqualManifest(v1manifest, m1); err != nil {
 		t.Fatal(err)
 	}
+
+	manifest, err = ms.Get(ctx, dgst, WithTag("badcontenttype"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	v1manifest, ok = manifest.(*schema1.SignedManifest)
+	if !ok {
+		t.Fatalf("Unexpected manifest type from Get: %T", manifest)
+	}
+
+	if err = checkEqualManifest(v1manifest, m1); err != nil {
+		t.Fatal(err)
+	}
 }
 
 func TestManifestFetchWithEtag(t *testing.T) {