Merge "Enhance StackResource update for more use cases"

heat/engine/resources/autoscaling.py

@@ -215,12 +215,15 @@ class InstanceGroup(stack_resource.StackResource):
         When shrinking, the newest instances will be removed.
         """
         new_template = self._create_template(new_capacity)
-        result = self.update_with_template(new_template, {})
-        for resource in self.nested():
-            if resource.state == ('CREATE', 'FAILED'):
-                resource.destroy()
+        try:
+            self.update_with_template(new_template, {})
+        except exception.Error as ex:
+            logger.error('Failed to resize instance group %s. Error: %s' %
+                         (self.name, ex))
+            for resource in self.nested():
+                if resource.state == ('CREATE', 'FAILED'):
+                    resource.destroy()
         self._lb_reload()
-        return result
 
     def _lb_reload(self):
         '''

heat/engine/stack_resource.py

@@ -113,9 +113,25 @@ class StackResource(resource.Resource):
                              environment.Environment(user_params),
                              timeout_mins=timeout_mins,
                              disable_rollback=True,
-                             parent_resource=self)
+                             parent_resource=self,
+                             owner_id=self.stack.id)
         stack.validate()
-        return self._nested.update(stack)
+
+        nested_stack = self.nested()
+        if nested_stack is None:
+            raise exception.Error(_('Cannot update %s, stack not created')
+                                  % self.name)
+
+        if not hasattr(type(self), 'attributes_schema'):
+            self.attributes = None
+            self._outputs_to_attribs(child_template)
+
+        nested_stack.update(stack)
+
+        if nested_stack.state != (nested_stack.UPDATE,
+                                  nested_stack.COMPLETE):
+            raise exception.Error("Nested stack update failed: %s" %
+                                  nested_stack.status_reason)
 
     def delete_nested(self):
         '''

heat/tests/test_stack_resource.py

@@ -12,6 +12,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+
+import mox
+
 from heat.common import template_format
 from heat.common import exception
 from heat.engine import environment
@@ -167,6 +170,35 @@ class StackResourceTest(HeatTestCase):
             self.parent_stack.context, self.stack.id)
         self.assertEqual(saved_stack.owner_id, self.parent_stack.id)
 
+    @utils.stack_delete_after
+    def test_update_with_template_state_err(self):
+        """
+        update_with_template_state_err method should raise error when update
+        task is done but the nested stack is in (UPDATE, FAILED) state.
+        """
+        create_creator = self.parent_resource.create_with_template(
+            self.simple_template, {})
+        create_creator.run_to_completion()
+        self.stack = self.parent_resource.nested()
+
+        new_templ = self.simple_template.copy()
+        inst_snippet = new_templ["Resources"]["WebServer"].copy()
+        new_templ["Resources"]["WebServer2"] = inst_snippet
+
+        def change_state(stack):
+            self.stack.state_set(parser.Stack.UPDATE, parser.Stack.FAILED, '')
+
+        self.m.StubOutWithMock(self.stack, 'update')
+        self.stack.update(mox.IgnoreArg()).WithSideEffects(change_state)
+        self.m.ReplayAll()
+
+        try:
+            self.parent_resource.update_with_template(new_templ, {})
+        except exception.Error as ex:
+            self.assertEqual('Nested stack update failed: ', ex.message)
+
+        self.m.VerifyAll()
+
     @utils.stack_delete_after
     def test_load_nested_ok(self):
         self.parent_resource.create_with_template(self.templ,