Check aodh api after a change.

The first query against the aodh api after a restart seems to
fail. So, check the api after a restart with a tenacity wrapper.

zaza/openstack/charm_tests/aodh/tests.py

@@ -17,6 +17,7 @@
 """Encapsulate Aodh testing."""
 
 import logging
+import tenacity
 
 import zaza.model
 import zaza.openstack.charm_tests.test_utils as test_utils
@@ -59,6 +60,12 @@ class AodhTest(test_utils.OpenStackBaseTest):
             logging.info('Waiting for alarm cache to clear')
             telemetry_utils.alarm_cache_wait()
 
+    @tenacity.retry(wait=tenacity.wait_exponential(multiplier=1, max=60),
+                    reraise=True, stop=tenacity.stop_after_attempt(8))
+    def query_aodh_api(self):
+        """Check that aodh api is responding."""
+        self.aodh_client.alarm.list()
+
     @property
     def services(self):
         """Return a list of the service that should be running."""
@@ -122,6 +129,7 @@ class AodhTest(test_utils.OpenStackBaseTest):
             {'DEFAULT': {'debug': ['False']}},
             {'DEFAULT': {'debug': ['True']}},
             self.services)
+        self.query_aodh_api()
 
     def test_901_pause_resume(self):
         """Run pause and resume tests.
@@ -133,3 +141,4 @@ class AodhTest(test_utils.OpenStackBaseTest):
                 self.services,
                 pgrep_full=False):
             logging.info("Testing pause resume")
+        self.query_aodh_api()