Merge "Implement enforcement model logic in Manager"

keystone/limit/core.py

@@ -18,6 +18,7 @@ from keystone.common import manager
 from keystone.common import provider_api
 import keystone.conf
 from keystone import exception
+from keystone.limit import models
 
 
 CONF = keystone.conf.CONF
@@ -35,6 +36,10 @@ class Manager(manager.Manager):
         unified_limit_driver = CONF.unified_limit.driver
         super(Manager, self).__init__(unified_limit_driver)
 
+        self.enforcement_model = models.get_enforcement_model_from_config(
+            CONF.unified_limit.enforcement_model
+        )
+
     def _assert_resource_exist(self, unified_limit, target):
         try:
             service_id = unified_limit.get('service_id')
@@ -56,6 +61,13 @@ class Manager(manager.Manager):
             raise exception.ValidationError(attribute='project_id',
                                             target=target)
 
+    def get_model(self):
+        """Return information of the configured enforcement model."""
+        return {
+            'name': self.enforcement_model.name,
+            'description': self.enforcement_model.description
+        }
+
     def create_registered_limits(self, registered_limits):
         for registered_limit in registered_limits:
             self._assert_resource_exist(registered_limit, 'registered_limit')

keystone/limit/models/__init__.py

@@ -0,0 +1,29 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+from keystone.limit.models import flat
+
+
+def get_enforcement_model_from_config(enforcement_model):
+    """Factory that returns an enforcement model object based on configuration.
+
+    :param enforcement_model str: A string, usually from a configuration
+                                  option, representing the name of the
+                                  enforcement model
+    :returns: an `Model` object
+
+    """
+    # NOTE(lbragstad): The configuration option set is strictly checked by the
+    # ``oslo.config`` object. If someone passes in a garbage value, it will
+    # fail before it gets to this point.
+    if enforcement_model == 'flat':
+        return flat.Model()

keystone/limit/models/flat.py

@@ -0,0 +1,22 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+
+# TODO(lbragstad): This should inherit from an abstract interface so that we
+# ensure all models implement the same things.
+class Model(object):
+
+    name = 'flat'
+    description = (
+        'Limit enforcement and validation does not take project hierarchy '
+        'into consideration.'
+    )

keystone/tests/unit/limit/test_backends.py

@@ -394,6 +394,20 @@ class RegisteredLimitTests(object):
 
 class LimitTests(object):
 
+    def test_default_enforcement_model_is_flat(self):
+        expected = {
+            'description': ('Limit enforcement and validation does not take '
+                            'project hierarchy into consideration.'),
+            'name': 'flat'
+        }
+        self.assertEqual(expected, PROVIDERS.unified_limit_api.get_model())
+
+    def test_registering_unsupported_enforcement_model_fails(self):
+        self.assertRaises(
+            ValueError, self.config_fixture.config, group='unified_limit',
+            enforcement_model=uuid.uuid4().hex
+        )
+
     def test_create_limit(self):
         # create one, return it.
         limit_1 = unit.new_limit_ref(