Require cross-mounting

Signed-off-by: Peter Engelbert <pmengelbert@gmail.com>

conformance/02_push_test.go

@@ -206,21 +206,14 @@ var test02Push = func() {
 					SetQueryParam("from", client.Config.DefaultName)
 				resp, err := client.Do(req)
 				Expect(err).To(BeNil())
-				Expect(resp.StatusCode()).To(SatisfyAny(
-					Equal(http.StatusCreated),
-					Equal(http.StatusMethodNotAllowed),
-				))
+				Expect(resp.StatusCode()).To(Equal(http.StatusCreated))
+				Expect(resp.GetRelativeLocation()).To(ContainSubstring(crossmountNamespace))
 
-				lastResponse = nil
-				if resp.StatusCode() == http.StatusCreated {
-					lastResponse = resp
-					Expect(lastResponse.GetRelativeLocation()).ToNot(BeEmpty())
-				}
+				lastResponse = resp
 			})
 
 			g.Specify("GET request to test digest within cross-mount namespace should return 200", func() {
 				SkipIfDisabled(push)
-				RunOnlyIfNot(lastResponse == nil)
 
 				req := client.NewRequest(reggie.GET, lastResponse.GetRelativeLocation())
 				resp, err := client.Do(req)

conformance/README.md

@@ -106,8 +106,8 @@ environment:
 OCI_SKIP_EMPTY_LAYER_PUSH_TEST=1
 ```
 
-Some registries allow cross-repository blob mounting.  As such, the test suite will need access to a second namespace.
-This namespace may need to be configured on the server-side in advance, and it is specified by setting the following in
+The test suite will need access to a second namespace. This namespace is used to check support for cross-repository mounting
+of blobs, and may need to be configured on the server-side in advance. It is specified by setting the following in
 the environment:
 
 ```

spec.md

@@ -321,6 +321,8 @@ Location: <blob-location>
 The digest contained in the `Location` header MAY be different from that of the blob that was mounted. As such, a client
 SHOULD use the digest found in the path from this header and SHOULD NOT use the digest of the blob that was mounted.
 
+If the source blob is not found, the response MUST be `404 Not Found`.
+
 ##### Pushing Manifests
 
 To push a manifest, perform a `PUT` request to a path in the following format, and with the following headers
@@ -445,7 +447,7 @@ of this specification.
 | end-8b | `GET`    | `/v2/<name>/tags/list?n=<integer>&last=<integer>`                 | `200`                              | `404`                           |
 | end-9  | `DELETE` | `/v2/<name>/manifests/<reference>`                                | `202`                              | `404`/`400`/`405`               |
 | end-10 | `DELETE` | `/v2/<name>/blobs/<digest>`                                       | `202`                              | `404`/`405`                     |
-| end-11 | `POST`   | `/v2/<name>/blobs/uploads/?mount=<digest>&from=<other_namespace>` | `201`                              | `405`                           |
+| end-11 | `POST`   | `/v2/<name>/blobs/uploads/?mount=<digest>&from=<other_namespace>` | `201`                              | `404`                           |
 
 #### Error Codes