Support keystone regions

This change enables keystone region support by defining the option
'region_name' in 'heat_client' section:

* magnum searchs only in region_name region for heat endpoint when
  region_name is not None,
* otherwise magnum search in all regions.

DocImpact
Closes-Bug: #1437049

Change-Id: Ib2895e7b56e48d6dfa8fe4680e12fc897d5cef03

etc/magnum/magnum.conf.sample

@@ -486,6 +486,10 @@
 # From magnum
 #
 
+# Region in Identity service catalog to use for
+# communication with the OpenStack service. (string value)
+#region_name = None
+
 # Type of endpoint in Identity service catalog to use for
 # communication with the OpenStack service. (string value)
 #endpoint_type = publicURL

magnum/common/clients.py

@@ -25,6 +25,10 @@ LOG = logging.getLogger(__name__)
 
 
 heat_client_opts = [
+    cfg.StrOpt('region_name',
+               default=None,
+               help=_('Region in Identity service catalog to use for '
+                      'communication with the OpenStack service.')),
     cfg.StrOpt('endpoint_type',
                default='publicURL',
                help=_(
@@ -80,8 +84,10 @@ class OpenStackClients(object):
             return self._heat
 
         endpoint_type = self._get_client_option('heat', 'endpoint_type')
+        region_name = self._get_client_option('heat', 'region_name')
         endpoint = self.url_for(service_type='orchestration',
-                                endpoint_type=endpoint_type)
+                                endpoint_type=endpoint_type,
+                                region_name=region_name)
 
         args = {
             'endpoint': endpoint,

magnum/tests/common/test_clients.py

@@ -12,6 +12,7 @@
 
 from heatclient.v1 import client as heatclient
 import mock
+from oslo_config import cfg
 
 from magnum.common import clients
 from magnum.common import exception
@@ -32,7 +33,8 @@ class ClientsTest(base.BaseTestCase):
     @mock.patch.object(heatclient, 'Client')
     @mock.patch.object(clients.OpenStackClients, 'url_for')
     @mock.patch.object(clients.OpenStackClients, 'auth_url')
-    def test_clients_heat(self, mock_auth, mock_url, mock_call):
+    def _test_clients_heat(self, expected_region_name, mock_auth, mock_url,
+                          mock_call):
         mock_auth.__get__ = mock.Mock(return_value="keystone_url")
         con = mock.MagicMock()
         con.auth_token = "3bcc3d3a03f44e3d8377f9247b0ad155"
@@ -47,7 +49,15 @@ class ClientsTest(base.BaseTestCase):
             auth_url='keystone_url', ca_file=None, key_file=None,
             password=None, insecure=False)
         mock_url.assert_called_once_with(service_type='orchestration',
-                                         endpoint_type='publicURL')
+                                         endpoint_type='publicURL',
+                                         region_name=expected_region_name)
+
+    def test_clients_heat(self):
+        self._test_clients_heat(None)
+
+    def test_clients_heat_region(self):
+        cfg.CONF.set_override('region_name', 'myregion', group='heat_client')
+        self._test_clients_heat('myregion')
 
     def test_clients_heat_noauth(self):
         con = mock.MagicMock()