ref(client+controller): iterate dicts directly to avoid copying

dict.keys() creates a list which is a copy of a dict's keys,
which in these cases wastes memory and isn't pythonic coding.

Author: mboersma

client/deis.py

@@ -1357,7 +1357,7 @@ def config_pull(self, args):
             # write env_dict to .env
             try:
                 with open('.env', 'w') as f:
-                    for i in env_dict.keys():
+                    for i in env_dict:
                         f.write("{}={}\n".format(i, env_dict[i]))
             except IOError:
                 self._logger.error('could not write to local env')
@@ -1744,7 +1744,7 @@ def ps_list(self, args, app=None):
         c_map = {}
         for item in processes['results']:
             c_map.setdefault(item['type'], []).append(item)
-        for c_type in c_map.keys():
+        for c_type in c_map:
             self._logger.info("--- {c_type}: ".format(**locals()))
             for c in c_map[c_type]:
                 self._logger.info("{type}.{num} {state} ({release})".format(**c))

controller/api/models.py

@@ -230,7 +230,7 @@ def scale(self, user, structure):  # noqa
         release = self.release_set.latest()
         # test for available process types
         available_process_types = release.build.procfile or {}
-        for container_type in requested_structure.keys():
+        for container_type in requested_structure:
             if container_type == 'cmd':
                 continue  # allow docker cmd types in case we don't have the image source
             if container_type not in available_process_types:
@@ -242,6 +242,7 @@ def scale(self, user, structure):  # noqa
         # iterate and scale by container type (web, worker, etc)
         changed = False
         to_add, to_remove = [], []
+        # iterate on a copy of the container_type keys
         for container_type in requested_structure.keys():
             containers = list(self.container_set.filter(type=container_type).order_by('created'))
             # increment new container nums off the most recent container
@@ -613,8 +614,8 @@ def save(self, **kwargs):
         try:
             previous_build = self.app.build_set.latest()
             to_destroy = []
-            for proctype in previous_build.procfile.keys():
-                if proctype not in self.procfile.keys():
+            for proctype in previous_build.procfile:
+                if proctype not in self.procfile:
                     for c in self.app.container_set.filter(type=proctype):
                         to_destroy.append(c)
             self.app._destroy_containers(to_destroy)

controller/api/tests/test_app.py

@@ -72,7 +72,7 @@ def test_response_data(self):
         response = self.client.post('/v1/apps', json.dumps(body),
                                     content_type='application/json',
                                     HTTP_AUTHORIZATION='token {}'.format(self.token))
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['uuid', 'created', 'updated', 'id', 'owner', 'url', 'structure'])
         expected = {
             'id': 'test',

controller/api/tests/test_auth.py

@@ -42,7 +42,7 @@ def test_auth(self):
         url = '/v1/auth/register'
         response = self.client.post(url, json.dumps(submit), content_type='application/json')
         self.assertEqual(response.status_code, 201)
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['id', 'last_login', 'is_superuser', 'username', 'first_name',
                                 'last_name', 'email', 'is_active', 'is_superuser', 'is_staff',
                                 'date_joined', 'groups', 'user_permissions'])
@@ -122,7 +122,7 @@ def test_auth_registration_admin_only_works(self):
                                     HTTP_AUTHORIZATION='token {}'.format(token))
 
         self.assertEqual(response.status_code, 201)
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['id', 'last_login', 'is_superuser', 'username', 'first_name',
                                 'last_name', 'email', 'is_active', 'is_superuser', 'is_staff',
                                 'date_joined', 'groups', 'user_permissions'])

controller/api/tests/test_build.py

@@ -95,7 +95,7 @@ def test_response_data(self):
         body = {'image': 'autotest/example'}
         response = self.client.post(url, json.dumps(body), content_type='application/json',
                                     HTTP_AUTHORIZATION='token {}'.format(self.token))
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['uuid', 'owner', 'created', 'updated', 'app', 'dockerfile',
                                 'image', 'procfile', 'sha'])
         expected = {

controller/api/tests/test_config.py

@@ -119,7 +119,7 @@ def test_response_data(self):
         body = {'values': json.dumps({'PORT': '5000'})}
         response = self.client.post(url, json.dumps(body), content_type='application/json',
                                     HTTP_AUTHORIZATION='token {}'.format(self.token))
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['uuid', 'owner', 'created', 'updated', 'app', 'values', 'memory',
                                 'cpu', 'tags'])
         expected = {

controller/api/tests/test_domain.py

@@ -39,7 +39,7 @@ def test_response_data(self):
         response = self.client.post('/v1/apps/test/domains', json.dumps(body),
                                     content_type='application/json',
                                     HTTP_AUTHORIZATION='token {}'.format(self.token))
-        for key in response.data.keys():
+        for key in response.data:
             self.assertIn(key, ['uuid', 'owner', 'created', 'updated', 'app', 'domain'])
         expected = {
             'owner': self.user.username,

controller/scheduler/swarm.py

@@ -123,12 +123,12 @@ def _get_hostname(self, application_name):
 
     def _get_portbindings(self, image):
         dictports = self.docker_cli.inspect_image(image)['ContainerConfig']['ExposedPorts']
-        for port, mapping in dictports.viewitems():
+        for port in dictports:
             dictports[port] = None
         return dictports
 
     def _get_ports(self, image):
         dictports = self.docker_cli.inspect_image(image)['ContainerConfig']['ExposedPorts']
-        return [int(port.split('/')[0]) for port in dictports.iterkeys()]
+        return [int(port.split('/')[0]) for port in dictports]
 
 SchedulerClient = SwarmClient