Adds keystone.region constraint

implements blueprint: heat-keystone-region-resource

Change-Id: I11a81bdd15035e76e0cfb9985a151c76aea9284d

heat/engine/clients/os/keystone.py

@@ -179,3 +179,11 @@ class KeystoneUserConstraint(constraints.BaseCustomConstraint):
 
     def validate_with_client(self, client, user):
         client.client_plugin('keystone').get_user_id(user)
+
+
+class KeystoneRegionConstraint(constraints.BaseCustomConstraint):
+
+    expected_exceptions = (exception.EntityNotFound,)
+
+    def validate_with_client(self, client, region):
+        client.client_plugin('keystone').get_region_id(region)

heat/tests/clients/test_keystone_client.py

@@ -145,6 +145,30 @@ class KeystoneUserConstraintTest(common.HeatTestCase):
         client_plugin_mock.get_user_id.assert_called_once_with('admin')
 
 
+class KeystoneRegionConstraintTest(common.HeatTestCase):
+
+    sample_uuid = '477e8273-60a7-4c41-b683-fdb0bc7cd151'
+
+    def test_expected_exceptions(self):
+        self.assertEqual((exception.EntityNotFound,),
+                         client.KeystoneRegionConstraint.expected_exceptions,
+                         "KeystoneRegionConstraint expected exceptions error")
+
+    def test_constraint(self):
+        constraint = client.KeystoneRegionConstraint()
+        client_mock = mock.MagicMock()
+        client_plugin_mock = mock.MagicMock()
+        client_plugin_mock.get_region_id.return_value = self.sample_uuid
+        client_mock.client_plugin.return_value = client_plugin_mock
+
+        self.assertIsNone(constraint.validate_with_client(client_mock,
+                                                          self.sample_uuid))
+
+        client_plugin_mock.get_region_id.assert_called_once_with(
+            self.sample_uuid
+        )
+
+
 class KeystoneClientPluginServiceTest(common.HeatTestCase):
 
     sample_uuid = '477e8273-60a7-4c41-b683-fdb0bc7cd152'

setup.cfg

@@ -102,6 +102,7 @@ heat.constraints =
     keystone.group = heat.engine.clients.os.keystone:KeystoneGroupConstraint
     keystone.service = heat.engine.clients.os.keystone:KeystoneServiceConstraint
     keystone.user = heat.engine.clients.os.keystone:KeystoneUserConstraint
+    keystone.region = heat.engine.clients.os.keystone:KeystoneRegionConstraint
     magnum.baymodel = heat.engine.clients.os.magnum:BaymodelConstraint
     manila.share_snapshot = heat.engine.clients.os.manila:ManilaShareSnapshotConstraint
     manila.share_network = heat.engine.clients.os.manila:ManilaShareNetworkConstraint