Raise exception when backup volume-backed instance

This patch will be backported to Juno and Icehouse so that
Nova can fail immediately to let user know that it's not
supported in that release.

Partial-Bug: #1313573

Change-Id: Ic84fa9e0b9c2d7b6cf49955aa4f0d44ade2b5397

nova/api/openstack/compute/contrib/admin_actions.py

@@ -289,6 +289,8 @@ class AdminActionsController(wsgi.Controller):
         except exception.InstanceInvalidState as state_error:
             common.raise_http_conflict_for_instance_invalid_state(state_error,
                     'createBackup', id)
+        except exception.InvalidRequest as e:
+            raise exc.HTTPBadRequest(explanation=e.format_message())
 
         resp = webob.Response(status_int=202)
 

nova/api/openstack/compute/plugins/v3/create_backup.py

@@ -69,6 +69,8 @@ class CreateBackupController(wsgi.Controller):
         except exception.InstanceInvalidState as state_error:
             common.raise_http_conflict_for_instance_invalid_state(state_error,
                     'createBackup', id)
+        except exception.InvalidRequest as e:
+            raise webob.exc.HTTPBadRequest(explanation=e.format_message())
 
         resp = webob.Response(status_int=202)
 

nova/compute/api.py

@@ -2120,8 +2120,17 @@ class API(base.Base):
         :returns: A dict containing image metadata
         """
         props_copy = dict(extra_properties, backup_type=backup_type)
-        image_meta = self._create_image(context, instance, name,
-                                       'backup', extra_properties=props_copy)
+
+        if self.is_volume_backed_instance(context, instance):
+            # TODO(flwang): The log level will be changed to INFO after
+            # string freeze (Liberty).
+            LOG.debug("It's not supported to backup volume backed instance.",
+                      context=context, instance=instance)
+            raise exception.InvalidRequest()
+        else:
+            image_meta = self._create_image(context, instance,
+                                            name, 'backup',
+                                            extra_properties=props_copy)
 
         # NOTE(comstud): Any changes to this method should also be made
         # to the backup_instance() method in nova/cells/messaging.py

nova/tests/unit/api/openstack/compute/contrib/test_create_backup.py

@@ -272,6 +272,28 @@ class CreateBackupTestsV21(admin_only_action_common.CommonMixin,
                           self.controller._create_backup,
                           self.req, fakes.FAKE_UUID, body=body)
 
+    def test_backup_volume_backed_instance(self):
+        body = {
+            'createBackup': {
+                'name': 'BackupMe',
+                'backup_type': 'daily',
+                'rotation': 3
+            },
+        }
+
+        common.check_img_metadata_properties_quota(self.context, {})
+        instance = self._stub_instance_get()
+        instance.image_ref = None
+
+        self.compute_api.backup(self.context, instance, 'BackupMe', 'daily', 3,
+                extra_properties={}).AndRaise(exception.InvalidRequest())
+
+        self.mox.ReplayAll()
+
+        self.assertRaises(webob.exc.HTTPBadRequest,
+                          self.controller._create_backup,
+                          self.req, instance['uuid'], body=body)
+
 
 class CreateBackupTestsV2(CreateBackupTestsV21):
     create_backup = create_backup_v2

nova/tests/unit/compute/test_compute_api.py

@@ -1742,6 +1742,13 @@ class _ComputeAPIUnitTestMixIn(object):
         self.mox.StubOutWithMock(self.compute_api.compute_rpcapi,
                                  'backup_instance')
 
+        if not is_snapshot:
+            self.mox.StubOutWithMock(self.compute_api,
+                                     'is_volume_backed_instance')
+
+            self.compute_api.is_volume_backed_instance(self.context,
+                instance).AndReturn(False)
+
         image_type = is_snapshot and 'snapshot' or 'backup'
 
         expected_sys_meta = dict(fake_sys_meta)
@@ -1885,6 +1892,19 @@ class _ComputeAPIUnitTestMixIn(object):
         self._test_snapshot_and_backup(is_snapshot=False,
                                        with_base_ref=True)
 
+    def test_backup_volume_backed_instance(self):
+        instance = self._create_instance_obj()
+
+        with mock.patch.object(self.compute_api,
+                               'is_volume_backed_instance',
+                               return_value=True) as mock_is_volume_backed:
+            self.assertRaises(exception.InvalidRequest,
+                              self.compute_api.backup, self.context,
+                              instance, 'fake-name', 'weekly',
+                              3, extra_properties={})
+            mock_is_volume_backed.assert_called_once_with(self.context,
+                                                          instance)
+
     def _test_snapshot_volume_backed(self, quiesce_required, quiesce_fails,
                                      vm_state=vm_states.ACTIVE):
         params = dict(locked=True, vm_state=vm_state)