Merge "Lazy load a project quotas's default values"

cinder/quota.py

@@ -188,6 +188,7 @@ class DbQuotaDriver(object):
         quotas = {}
         project_quotas = db.quota_get_all_by_project(context, project_id)
         allocated_quotas = None
+        default_quotas = None
         if usages:
             project_usages = db.quota_usage_get_all_by_project(context,
                                                                project_id)
@@ -206,20 +207,22 @@ class DbQuotaDriver(object):
         else:
             class_quotas = {}
 
-        # TODO(mc_nair): change this to be lazy loaded
-        default_quotas = self.get_defaults(context, resources, project_id)
-
         for resource in resources.values():
             # Omit default/quota class values
             if not defaults and resource.name not in project_quotas:
                 continue
 
-            quotas[resource.name] = dict(
-                limit=project_quotas.get(
-                    resource.name,
-                    class_quotas.get(resource.name,
-                                     default_quotas[resource.name])),
-            )
+            quota_val = project_quotas.get(resource.name)
+            if quota_val is None:
+                quota_val = class_quotas.get(resource.name)
+                if quota_val is None:
+                    # Lazy load the default quotas
+                    if default_quotas is None:
+                        default_quotas = self.get_defaults(
+                            context, resources, project_id)
+                    quota_val = default_quotas[resource.name]
+
+            quotas[resource.name] = {'limit': quota_val}
 
             # Include usages if desired.  This is optional because one
             # internal consumer of this interface wants to access the

cinder/tests/unit/test_quota.py

@@ -1063,6 +1063,24 @@ class DbQuotaDriverTestCase(DbQuotaDriverBaseTestCase):
                                                         reserved= 0)
                               ), result)
 
+    @mock.patch('cinder.quota.db.quota_get_all_by_project')
+    @mock.patch('cinder.quota.db.quota_class_get_default')
+    def test_get_project_quotas_lazy_load_defaults(
+            self, mock_defaults, mock_quotas):
+        mock_quotas.return_value = self._default_quotas_non_child
+        self.driver.get_project_quotas(
+            FakeContext('test_project', None),
+            quota.QUOTAS.resources, 'test_project', usages=False)
+        # Shouldn't load a project's defaults if all the quotas are already
+        # defined in the DB
+        self.assertFalse(mock_defaults.called)
+
+        mock_quotas.return_value = {}
+        self.driver.get_project_quotas(
+            FakeContext('test_project', None),
+            quota.QUOTAS.resources, 'test_project', usages=False)
+        self.assertTrue(mock_defaults.called)
+
     def test_get_root_project_with_subprojects_quotas(self):
         self._stub_get_by_project()
         self._stub_volume_type_get_all()
@@ -1171,8 +1189,7 @@ class DbQuotaDriverTestCase(DbQuotaDriverBaseTestCase):
 
         self.assertEqual(['quota_get_all_by_project',
                           'quota_usage_get_all_by_project',
-                          'quota_class_get_all_by_name',
-                          'quota_class_get_default', ], self.calls)
+                          'quota_class_get_all_by_name'], self.calls)
         self.assertEqual(dict(backups=dict(limit=10,
                                            in_use=2,
                                            reserved=0, ),