Remove unreachable code in API utils

The last line of method "get_rpc_resource" is unreachable. This
patch removes it. Also, add tests to this method.

Change-Id: Ib47ad473078f91b5ae238112b7acda14ea907ef2
Closes-Bug: 1470908

magnum/api/controllers/v1/utils.py

@@ -63,7 +63,6 @@ def get_rpc_resource(resource, resource_ident):
     :param resource_ident: the UUID or logical name of the resource.
 
     :returns: The RPC resource.
-    :raises: InvalidUuidOrName if the name or uuid provided is not valid.
     """
     resource = getattr(objects, resource)
 
@@ -72,8 +71,6 @@ def get_rpc_resource(resource, resource_ident):
 
     return resource.get_by_name(pecan.request.context, resource_ident)
 
-    raise exception.InvalidUuidOrName(name=resource_ident)
-
 
 def get_openstack_resource(manager, resource_ident, resource_type):
     """Get the openstack resource from the uuid or logical name.

magnum/tests/unit/api/controllers/v1/test_utils.py

@@ -51,6 +51,42 @@ class TestApiUtils(base.FunctionalTest):
                           utils.validate_sort_dir,
                           'fake-sort')
 
+    @mock.patch('pecan.request')
+    @mock.patch('magnum.objects.Bay.get_by_name')
+    @mock.patch('magnum.objects.Bay.get_by_uuid')
+    def test_get_rpc_resource_with_uuid(
+            self,
+            mock_get_by_uuid,
+            mock_get_by_name,
+            mock_request):
+        mock_bay = mock.MagicMock
+        mock_get_by_uuid.return_value = mock_bay
+        uuid = common_utils.generate_uuid()
+
+        returned_bay = utils.get_rpc_resource('Bay', uuid)
+
+        mock_get_by_uuid.assert_called_once_with(mock_request.context, uuid)
+        self.assertFalse(mock_get_by_name.called)
+        self.assertEqual(returned_bay, mock_bay)
+
+    @mock.patch('pecan.request')
+    @mock.patch('magnum.objects.Bay.get_by_name')
+    @mock.patch('magnum.objects.Bay.get_by_uuid')
+    def test_get_rpc_resource_with_name(
+            self,
+            mock_get_by_uuid,
+            mock_get_by_name,
+            mock_request):
+        mock_bay = mock.MagicMock
+        mock_get_by_name.return_value = mock_bay
+
+        returned_bay = utils.get_rpc_resource('Bay', 'fake-name')
+
+        self.assertFalse(mock_get_by_uuid.called)
+        mock_get_by_name.assert_called_once_with(mock_request.context,
+                                                 'fake-name')
+        self.assertEqual(returned_bay, mock_bay)
+
     @mock.patch.object(common_utils, 'is_uuid_like', return_value=True)
     def test_get_openstack_resource_by_uuid(self, fake_is_uuid_like):
         fake_manager = mock.MagicMock()