Do not access DB when it is in maintenance mode.

If the database is in maintenace mode do not attempt to access
it.

Depends-On: I5d8ed7d3935db5568c50f8d585e37a4d0cc6914f
Change-Id: I9550452e78608589592265fca9549a51c88d65bc

hooks/glance_relations.py

@@ -106,6 +106,7 @@ from charmhelpers.contrib.openstack.utils import (
     series_upgrade_complete,
     CompareOpenStackReleases,
     is_db_initialised,
+    is_db_maintenance_mode,
 )
 from charmhelpers.contrib.storage.linux.ceph import (
     send_request_if_needed,
@@ -192,6 +193,9 @@ def db_joined():
 @hooks.hook('shared-db-relation-changed')
 @restart_on_change(restart_map())
 def db_changed():
+    if is_db_maintenance_mode():
+        juju_log('Database maintenance mode, aborting hook.')
+        return
     release = os_release('glance-common')
     cmp_release = CompareOpenStackReleases(release)
 

unit_tests/test_glance_relations.py

@@ -106,6 +106,7 @@ TO_PATCH = [
     'sync_db_with_multi_ipv6_addresses',
     'delete_keyring',
     'get_relation_ip',
+    'is_db_maintenance_mode',
 ]
 
 
@@ -151,6 +152,7 @@ class GlanceRelationTests(CharmTestCase):
 
     @patch.object(relations, 'CONFIGS')
     def test_db_changed_missing_relation_data(self, configs):
+        self.is_db_maintenance_mode.return_value = False
         self.is_db_initialised.return_value = False
         configs.complete_contexts = MagicMock()
         configs.complete_contexts.return_value = []
@@ -161,6 +163,7 @@ class GlanceRelationTests(CharmTestCase):
 
     def _shared_db_test(self, configs, unit_name,
                         allowed_units='glance/0 glance/3'):
+        self.is_db_maintenance_mode.return_value = False
         self.relation_get.return_value = allowed_units
         self.local_unit.return_value = unit_name
         configs.complete_contexts = MagicMock()