Return default quota from API

Currently the dashboard and magnum clients are unable to get the default
quota of a project, if a project does not have a quota set. This is due
to the API returning a QuotaNotFound exception, rather than falling back
to the default quota.

The result is that dashboard is not displaying quotas correctly. It also
means users are not able to see their default quota.

This patch updates the API by returning the default quota instead of a
QuotaNotFound exception. This makes magnum behave similarly to how other
projects like designate handles quota.

Story: 2006307
Task: 36029
Change-Id: I1b278d221d0f15d92d67869cd3ac897d041eaf90

magnum/api/controllers/v1/quota.py

@@ -25,10 +25,13 @@ from magnum.api import utils as api_utils
 from magnum.api import validation
 from magnum.common import exception
 from magnum.common import policy
+import magnum.conf
 from magnum.i18n import _
 from magnum import objects
 from magnum.objects import fields
 
+CONF = magnum.conf.CONF
+
 
 class Quota(base.APIBase):
     """API representation of a project Quota.
@@ -157,10 +160,16 @@ class QuotaController(base.Controller):
         if not context.is_admin and project_id != context.project_id:
             raise exception.NotAuthorized()
 
-        quota = objects.Quota.get_quota_by_project_id_resource(context,
-                                                               project_id,
-                                                               resource)
-        return Quota.convert(quota)
+        try:
+            quota = objects.Quota.get_quota_by_project_id_resource(context,
+                                                                   project_id,
+                                                                   resource)
+            quota = Quota.convert(quota)
+        except exception.QuotaNotFound:
+            # If explicit quota was not set for the project, use default limit
+            quota = Quota(project_id=project_id,
+                          hard_limit=CONF.quotas.max_clusters_per_project)
+        return quota
 
     @expose.expose(Quota, body=Quota, status_code=201)
     @validation.enforce_valid_project_id_on_create()

magnum/tests/unit/api/controllers/v1/test_quota.py

@@ -16,11 +16,14 @@ from keystoneauth1 import exceptions as ka_exception
 
 from magnum.api.controllers.v1 import quota as api_quota
 from magnum.common import clients
+import magnum.conf
 from magnum.tests import base
 from magnum.tests.unit.api import base as api_base
 from magnum.tests.unit.api import utils as apiutils
 from magnum.tests.unit.objects import utils as obj_utils
 
+CONF = magnum.conf.CONF
+
 
 class TestQuotaObject(base.TestCase):
     def test_quota_init(self):
@@ -60,14 +63,27 @@ class TestQuota(api_base.FunctionalTest):
         self.assertEqual(quota.resource, response['resource'])
 
     @mock.patch("magnum.common.policy.enforce")
-    def test_get_one_not_found(self, mock_policy):
+    def test_get_one_no_config_default(self, mock_policy):
         mock_policy.return_value = True
         response = self.get_json(
-            '/quotas/fake_project/invalid_res',
+            '/quotas/fake_project/Cluster',
             expect_errors=True)
-        self.assertEqual(404, response.status_int)
-        self.assertEqual('application/json', response.content_type)
-        self.assertTrue(response.json['errors'])
+        self.assertEqual(200, response.status_int)
+        self.assertEqual('fake_project', response.json['project_id'])
+        self.assertEqual(CONF.quotas.max_clusters_per_project,
+                         response.json['hard_limit'])
+
+    @mock.patch("magnum.common.policy.enforce")
+    def test_get_one_with_config_default(self, mock_policy):
+        mock_policy.return_value = True
+        quota = 15
+        CONF.set_override('max_clusters_per_project', quota, group='quotas')
+        response = self.get_json(
+            '/quotas/fake_project/Cluster',
+            expect_errors=True)
+        self.assertEqual(200, response.status_int)
+        self.assertEqual('fake_project', response.json['project_id'])
+        self.assertEqual(quota, response.json['hard_limit'])
 
     def test_get_one_not_authorized(self):
         obj_utils.create_test_quota(self.context)
@@ -300,6 +316,7 @@ class TestQuota(api_base.FunctionalTest):
         response = self.get_json(
             '/quotas/%s/%s' % (project_id, resource),
             expect_errors=True)
-        self.assertEqual(404, response.status_int)
-        self.assertEqual('application/json', response.content_type)
-        self.assertTrue(response.json['errors'])
+        self.assertEqual(200, response.status_int)
+        self.assertEqual('fake_project', response.json['project_id'])
+        self.assertEqual(CONF.quotas.max_clusters_per_project,
+                         response.json['hard_limit'])