Merge "PATCH update reuse existing template"

heat/api/openstack/v1/stacks.py

@@ -66,6 +66,7 @@ class InstantiationData(object):
         to distinguish.
         """
         self.data = data
+        self.patch = patch
         if patch:
             self.data[rpc_api.PARAM_EXISTING] = True
 
@@ -92,6 +93,7 @@ class InstantiationData(object):
         Get template file contents, either inline, from stack adopt data or
         from a URL, in JSON or YAML format.
         """
+        template_data = None
         if rpc_api.PARAM_ADOPT_STACK_DATA in self.data:
             adopt_data = self.data[rpc_api.PARAM_ADOPT_STACK_DATA]
             try:
@@ -112,8 +114,12 @@ class InstantiationData(object):
             except IOError as ex:
                 err_reason = _('Could not retrieve template: %s') % ex
                 raise exc.HTTPBadRequest(err_reason)
-        else:
-            raise exc.HTTPBadRequest(_("No template specified"))
+
+        if template_data is None:
+            if self.patch:
+                return None
+            else:
+                raise exc.HTTPBadRequest(_("No template specified"))
 
         with self.parse_error_check('Template'):
             return template_format.parse(template_data)

heat/engine/service.py

@@ -791,7 +791,8 @@ class EngineService(service.Service):
 
         # Now parse the template and any parameters for the updated
         # stack definition.  If PARAM_EXISTING is specified, we merge
-        # any environment provided into the existing one.
+        # any environment provided into the existing one and attempt
+        # to use the existing stack template, if one is not provided.
         if args.get(rpc_api.PARAM_EXISTING, None):
             existing_env = current_stack.env.user_env_as_dict()
             existing_params = existing_env[env_fmt.PARAMETERS]
@@ -804,15 +805,42 @@ class EngineService(service.Service):
 
             new_files = current_stack.t.files.copy()
             new_files.update(files or {})
+
+            if template is not None:
+                new_template = template
+            elif (current_stack.convergence or
+                  current_stack.status == current_stack.COMPLETE):
+                # If convergence is enabled, or the stack is complete, we can
+                # just use the current template...
+                new_template = current_stack.t.t
+            else:
+                # ..but if it's FAILED without convergence things may be in an
+                # inconsistent state, so we try to fall back on a stored copy
+                # of the previous template
+                if current_stack.prev_raw_template_id is not None:
+                    # Use the stored previous template
+                    prev_t = templatem.Template.load(
+                        cnxt, current_stack.prev_raw_template_id)
+                    new_template = prev_t.t
+                else:
+                    # Nothing we can do, the failed update happened before
+                    # we started storing prev_raw_template_id
+                    LOG.error("PATCH update to FAILED stack only possible if "
+                              "convergence enabled or previous template "
+                              "stored")
+                    msg = _('PATCH update to non-COMPLETE stack')
+                    raise exception.NotSupported(feature=msg)
         else:
             new_env = environment.Environment(params)
             new_files = files
-        tmpl = templatem.Template(template, files=new_files, env=new_env)
+            new_template = template
+
+        tmpl = templatem.Template(new_template, files=new_files, env=new_env)
 
         current_stack, updated_stack = self._prepare_stack_updates(
             cnxt, current_stack, tmpl, params, files, args)
 
-        if current_stack.get_kwargs_for_cloning()['convergence']:
+        if current_stack.convergence:
             current_stack.converge_stack(template=tmpl,
                                          new_stack=updated_stack)
         else:

heat/tests/api/openstack_v1/test_stacks.py

@@ -1661,6 +1661,41 @@ class StackControllerTest(tools.ControllerTest, common.HeatTestCase):
         self.assertEqual(403, resp.status_int)
         self.assertIn('403 Forbidden', six.text_type(resp))
 
+    def test_update_with_existing_template(self, mock_enforce):
+        self._mock_enforce_setup(mock_enforce, 'update_patch', True)
+        identity = identifier.HeatIdentifier(self.tenant, 'wordpress', '6')
+        body = {'template': None,
+                'parameters': {},
+                'files': {},
+                'timeout_mins': 30}
+
+        req = self._patch('/stacks/%(stack_name)s/%(stack_id)s' % identity,
+                          json.dumps(body))
+
+        self.m.StubOutWithMock(rpc_client.EngineClient, 'call')
+        rpc_client.EngineClient.call(
+            req.context,
+            ('update_stack',
+             {'stack_identity': dict(identity),
+              'template': None,
+              'params': {'parameters': {},
+                         'encrypted_param_names': [],
+                         'parameter_defaults': {},
+                         'resource_registry': {}},
+              'files': {},
+              'args': {rpc_api.PARAM_EXISTING: True,
+                       'timeout_mins': 30}})
+        ).AndReturn(dict(identity))
+        self.m.ReplayAll()
+
+        self.assertRaises(webob.exc.HTTPAccepted,
+                          self.controller.update_patch,
+                          req, tenant_id=identity.tenant,
+                          stack_name=identity.stack_name,
+                          stack_id=identity.stack_id,
+                          body=body)
+        self.m.VerifyAll()
+
     def test_update_with_existing_parameters(self, mock_enforce):
         self._mock_enforce_setup(mock_enforce, 'update_patch', True)
         identity = identifier.HeatIdentifier(self.tenant, 'wordpress', '6')

heat/tests/engine/service/test_stack_update.py

@@ -601,6 +601,68 @@ class ServiceStackUpdateTest(common.HeatTestCase):
             user_creds_id=u'1', username='test_username')
         mock_load.assert_called_once_with(self.ctx, stack=s)
 
+    def test_stack_update_existing_template(self):
+        '''Update a stack using the same template.'''
+        stack_name = 'service_update_test_stack_existing_template'
+        api_args = {rpc_api.PARAM_TIMEOUT: 60,
+                    rpc_api.PARAM_EXISTING: True}
+        t = template_format.parse(tools.wp_template)
+        # Don't actually run the update as the mocking breaks it, instead
+        # we just ensure the expected template is passed in to the updated
+        # template, and that the update task is scheduled.
+        self.man.thread_group_mgr = tools.DummyThreadGroupMgrLogStart()
+
+        params = {}
+        stack = utils.parse_stack(t, stack_name=stack_name,
+                                  params=params)
+        stack.set_stack_user_project_id('1234')
+        self.assertEqual(stack.t.t,
+                         t)
+        stack.action = stack.CREATE
+        stack.status = stack.COMPLETE
+
+        with mock.patch('heat.engine.stack.Stack') as mock_stack:
+            mock_stack.load.return_value = stack
+            mock_stack.validate.return_value = None
+            result = self.man.update_stack(self.ctx, stack.identifier(),
+                                           None,
+                                           params,
+                                           None, api_args)
+            tmpl = mock_stack.call_args[0][2]
+            self.assertEqual(t,
+                             tmpl.t)
+            self.assertEqual(stack.identifier(), result)
+            self.assertEqual(1, len(self.man.thread_group_mgr.started))
+
+    def test_stack_update_existing_failed(self):
+        '''Update a stack using the same template doesn't work when FAILED.'''
+        stack_name = 'service_update_test_stack_existing_template'
+        api_args = {rpc_api.PARAM_TIMEOUT: 60,
+                    rpc_api.PARAM_EXISTING: True}
+        t = template_format.parse(tools.wp_template)
+        # Don't actually run the update as the mocking breaks it, instead
+        # we just ensure the expected template is passed in to the updated
+        # template, and that the update task is scheduled.
+        self.man.thread_group_mgr = tools.DummyThreadGroupMgrLogStart()
+
+        params = {}
+        stack = utils.parse_stack(t, stack_name=stack_name,
+                                  params=params)
+        stack.set_stack_user_project_id('1234')
+        self.assertEqual(stack.t.t,
+                         t)
+        stack.action = stack.UPDATE
+        stack.status = stack.FAILED
+
+        ex = self.assertRaises(dispatcher.ExpectedException,
+                               self.man.update_stack,
+                               self.ctx, stack.identifier(),
+                               None, params, None, api_args)
+
+        self.assertEqual(exception.NotSupported, ex.exc_info[0])
+        self.assertIn("PATCH update to non-COMPLETE stack",
+                      six.text_type(ex.exc_info[1]))
+
 
 class ServiceStackUpdatePreviewTest(common.HeatTestCase):