Add List Available Zones test cases for RBAC.

This commit includes list available zones tests for RBAC
The operation is only
- List available zones

Depends-On: I7e5e706c44136e0b565f3ee18e15f1166d82040d

Change-Id: I39b10e06d9bcbf6fa939ee4603e830bb935e716b
diff --git a/patrole_tempest_plugin/tests/api/network/test_availability_zones_rbac.py b/patrole_tempest_plugin/tests/api/network/test_availability_zones_rbac.py
new file mode 100644
index 0000000..b1c806b
--- /dev/null
+++ b/patrole_tempest_plugin/tests/api/network/test_availability_zones_rbac.py
@@ -0,0 +1,48 @@
+# Copyright 2018 AT&T Corporation.
+# All Rights Reserved.
+#
+#    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 tempest.common import utils
+from tempest.lib import decorators
+
+from patrole_tempest_plugin import rbac_rule_validation
+from patrole_tempest_plugin.tests.api.network import rbac_base as base
+
+
+class AvailabilityZoneExtRbacTest(base.BaseNetworkExtRbacTest):
+
+    @classmethod
+    def skip_checks(cls):
+        super(AvailabilityZoneExtRbacTest, cls).skip_checks()
+        if not utils.is_extension_enabled('availability_zone',
+                                          'network'):
+            msg = "network_availability_zone extension not enabled."
+            raise cls.skipException(msg)
+
+    @rbac_rule_validation.action(service="neutron",
+                                 rules=["get_availability_zone"])
+    @decorators.idempotent_id('3c521be8-c32e-11e8-a611-080027758b73')
+    def test_list_availability_zone_rbac(self):
+
+        """List all available zones.
+
+        RBAC test for the neutron ``list_availability_zones``
+        function and the ``get_availability_zone`` policy
+        """
+        admin_resources = (self.ntp_client.list_availability_zones()
+                           ["availability_zones"])
+        with self.rbac_utils.override_role_and_validate_list(
+                self, admin_resources=admin_resources) as ctx:
+            ctx.resources = (self.ntp_client.list_availability_zones()
+                             ['availability_zones'])