Return image references in ImageStatus()

The image's canonical reference is a name with a digest of the image's
manifest, so compute and return that value as the image's reference in
ImageStatus() and in ContainerStatus().

We don't auto-store a name based on the image digest when we pull one by
tag, but then CRI doesn't need us to do that.

Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>

server/container_status.go

@@ -46,6 +46,14 @@ func (s *Server) ContainerStatus(ctx context.Context, req *pb.ContainerStatusReq
 	cState := s.Runtime().ContainerStatus(c)
 	rStatus := pb.ContainerState_CONTAINER_UNKNOWN
 
+	imageName := c.Image()
+	status, err := s.StorageImageServer().ImageStatus(s.ImageContext(), imageName)
+	if err != nil {
+		return nil, err
+	}
+
+	resp.Status.ImageRef = status.ImageRef
+
 	// If we defaulted to exit code -1 earlier then we attempt to
 	// get the exit code from the exit file again.
 	if cState.ExitCode == -1 {

server/image_status.go

@@ -42,10 +42,10 @@ func (s *Server) ImageStatus(ctx context.Context, req *pb.ImageStatusRequest) (*
 	}
 	resp := &pb.ImageStatusResponse{
 		Image: &pb.Image{
-			Id:       status.ID,
-			RepoTags: status.Names,
-			Size_:    *status.Size,
-			// TODO: https://github.com/kubernetes-incubator/cri-o/issues/531
+			Id:          status.ID,
+			RepoTags:    status.Names,
+			RepoDigests: status.Digests,
+			Size_:       *status.Size,
 		},
 	}
 	logrus.Debugf("ImageStatusResponse: %+v", resp)