Don't use gnocchiclient during publisher init

We can't create archive policies in publisher init because if it fail
because Gnocchi is not yet ready the publisher fail to load. Ceilometer
will work, but samples will go to nowhere.

This change creates/checks archive policies when we publish a sample for
the very first time. If that fail because Gnocchi is not ready, this
will just retry next time Ceilometer will publish samples.

Closes-Bug: #1752420

Change-Id: Ib6b4da54592ad99a4e6561a73473b6c7ec73a21f

ceilometer/publisher/gnocchi.py

@@ -246,7 +246,7 @@ def __init__(self, conf, parsed_url):
         self._already_logged_event_types = set()
         self._already_logged_metric_names = set()
 
-        self.ensures_archives_policies()
+        self._already_configured_archive_policies = False
 
     @staticmethod
     def _load_definitions(conf, archive_policy_override,
@@ -273,11 +273,13 @@ def _load_definitions(conf, archive_policy_override,
         return resource_defs, data.get("archive_policies", [])
 
     def ensures_archives_policies(self):
-        for ap in self.archive_policies_definition:
-            try:
-                self._gnocchi.archive_policy.get(ap["name"])
-            except gnocchi_exc.ArchivePolicyNotFound:
-                self._gnocchi.archive_policy.create(ap)
+        if not self._already_configured_archive_policies:
+            for ap in self.archive_policies_definition:
+                try:
+                    self._gnocchi.archive_policy.get(ap["name"])
+                except gnocchi_exc.ArchivePolicyNotFound:
+                    self._gnocchi.archive_policy.create(ap)
+            self._already_configured_archive_policies = True
 
     @property
     def gnocchi_project_id(self):
@@ -325,6 +327,8 @@ def _get_resource_definition_from_event(self, event_type):
                 return rd, operation
 
     def publish_samples(self, data):
+        self.ensures_archives_policies()
+
         # NOTE(sileht): skip sample generated by gnocchi itself
         data = [s for s in data if not self._is_gnocchi_activity(s)]
         data.sort(key=operator.attrgetter('resource_id'))

ceilometer/tests/unit/publisher/test_gnocchi.py

@@ -649,8 +649,6 @@ def test_event_workflow(self, fakeclient_cls):
         self.useFixture(utils_fixture.TimeFixture(now))
 
         expected_calls = [
-            mock.call.archive_policy.get("ceilometer-low"),
-            mock.call.archive_policy.get("ceilometer-low-rate"),
             mock.call.resource.search('instance_network_interface',
                                       search_params),
             mock.call.resource.search('instance_disk', search_params),
@@ -680,7 +678,7 @@ def test_event_workflow(self, fakeclient_cls):
                                        IMAGE_DELETE_START,
                                        VOLUME_DELETE_START,
                                        FLOATINGIP_DELETE_END])
-        self.assertEqual(10, len(fakeclient.mock_calls))
+        self.assertEqual(8, len(fakeclient.mock_calls))
         for call in expected_calls:
             self.assertIn(call, fakeclient.mock_calls)