fix(controller): merge structure with new structure

If the old structure contained values like {'web': 0}, the container
count would be zero, so the resulting vals structure would be an empty
dictionary. By taking the "requested" structure and updating it with
the actual container queryset, values like {'web': 0} will stay the
same. From that result, the structure will not be considered in an
"initial" state[1], which means that a new deploy will not cause the
containers to be accidentally scaled back up to one.

[1]: https://github.com/deis/deis/blob/ebc3df479a672acb4a81525ba1edd0fb4d70a6a9/controller/api/models.py#L605

Author: Matthew Fisher

controller/api/models.py

@@ -275,7 +275,9 @@ def scale(self, user, structure):  # noqa
         # save new structure to the database
         vals = self.container_set.exclude(type='run').values(
             'type').annotate(Count('pk')).order_by()
-        self.structure = {v['type']: v['pk__count'] for v in vals}
+        new_structure = structure.copy()
+        new_structure.update({v['type']: v['pk__count'] for v in vals})
+        self.structure = new_structure
         self.save()
         return changed
 

controller/api/tests/test_build.py

@@ -253,3 +253,48 @@ def test_unauthorized_user_cannot_modify_build(self):
         response = self.client.post(url, json.dumps(body), content_type='application/json',
                                     HTTP_AUTHORIZATION='token {}'.format(unauthorized_token))
         self.assertEqual(response.status_code, 403)
+
+    @mock.patch('requests.post', mock_import_repository_task)
+    def test_new_build_does_not_scale_up_automatically(self):
+        """
+        After the first initial deploy, if the containers are scaled down to zero,
+        they should stay that way on a new release.
+        """
+        url = '/v1/apps'
+        response = self.client.post(url, HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 201)
+        app_id = response.data['id']
+        # post a new build
+        url = "/v1/apps/{app_id}/builds".format(**locals())
+        body = {'image': 'autotest/example',
+                'sha': 'a'*40,
+                'procfile': json.dumps({'web': 'node server.js',
+                                        'worker': 'node worker.js'})}
+        response = self.client.post(url, json.dumps(body), content_type='application/json',
+                                    HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 201)
+        url = "/v1/apps/{app_id}/containers/web".format(**locals())
+        response = self.client.get(url,
+                                   HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(len(response.data['results']), 1)
+        # scale to zero
+        url = "/v1/apps/{app_id}/scale".format(**locals())
+        body = {'web': 0}
+        response = self.client.post(url, json.dumps(body), content_type='application/json',
+                                    HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 204)
+        # post another build
+        url = "/v1/apps/{app_id}/builds".format(**locals())
+        body = {'image': 'autotest/example',
+                'sha': 'a'*40,
+                'procfile': json.dumps({'web': 'node server.js',
+                                        'worker': 'node worker.js'})}
+        response = self.client.post(url, json.dumps(body), content_type='application/json',
+                                    HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 201)
+        url = "/v1/apps/{app_id}/containers/web".format(**locals())
+        response = self.client.get(url,
+                                   HTTP_AUTHORIZATION='token {}'.format(self.token))
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(len(response.data['results']), 0)