Notify clients of series upgrade

When the percona cluster is undergoing a series upgrade, clients
should suspend db activity in their hooks (like db migrations).

This change sents a notification of upgrade

Change-Id: I9d02180fcb0fec6bd017c6150bfca5963896fd2f

actions/actions.py

@@ -12,6 +12,8 @@ from charmhelpers.core.hookenv import (
     action_get,
     action_set,
     action_fail,
+    relation_ids,
+    relation_set,
     leader_set,
     is_leader,
 )
@@ -21,6 +23,10 @@ from charmhelpers.core.host import (
     lsb_release,
 )
 
+from charmhelpers.contrib.openstack.utils import (
+    DB_SERIES_UPGRADING_KEY,
+)
+
 from percona_utils import (
     pause_unit_helper,
     resume_unit_helper,
@@ -60,6 +66,10 @@ def complete_cluster_series_upgrade(args):
         # Unset cluster_series_upgrading
         leader_set(cluster_series_upgrading="")
         leader_set(cluster_series_upgrade_leader="")
+        for r_id in relation_ids('shared-db'):
+            relation_set(
+                relation_id=r_id,
+                relation_settings={DB_SERIES_UPGRADING_KEY: None})
     config_changed()
 
 

charmhelpers/contrib/openstack/utils.py

@@ -293,6 +293,10 @@ PACKAGE_CODENAMES = {
 
 DEFAULT_LOOPBACK_SIZE = '5G'
 
+DB_SERIES_UPGRADING_KEY = 'cluster-series-upgrading'
+
+DB_MAINTENANCE_KEYS = [DB_SERIES_UPGRADING_KEY]
+
 
 class CompareOpenStackReleases(BasicStringComparator):
     """Provide comparisons of OpenStack releases.

hooks/percona_hooks.py

@@ -67,6 +67,7 @@ from charmhelpers.contrib.charmsupport import nrpe
 from charmhelpers.contrib.hardening.harden import harden
 from charmhelpers.contrib.hardening.mysql.checks import run_mysql_checks
 from charmhelpers.contrib.openstack.utils import (
+    DB_SERIES_UPGRADING_KEY,
     is_unit_paused_set,
     is_unit_upgrading_set,
     set_unit_upgrading,
@@ -356,6 +357,10 @@ def prepare():
         leader_set(cluster_series_upgrading=True)
         leader_set(
             cluster_series_upgrade_leader=get_relation_ip('cluster'))
+        for r_id in relation_ids('shared-db'):
+            relation_set(
+                relation_id=r_id,
+                relation_settings={DB_SERIES_UPGRADING_KEY: True})
     else:
         hosts = [leader_get('cluster_series_upgrade_leader')]
 
@@ -945,6 +950,11 @@ def leader_settings_changed():
     # NOTE(tkurek): deconfigure old leader
     if relation_ids('slave'):
         deconfigure_slave()
+    if not leader_get('cluster_series_upgrading'):
+        for r_id in relation_ids('shared-db'):
+            relation_set(
+                relation_id=r_id,
+                relation_settings={DB_SERIES_UPGRADING_KEY: None})
 
 
 @hooks.hook('leader-elected')

test-requirements.txt

@@ -15,3 +15,23 @@ stestr>=2.2.0
 coverage>=4.5.2
 keyring==18.0.1
 setuptools<=40.0.0
+# BEGIN: Amulet OpenStack Charm Helper Requirements
+# Liberty client lower constraints
+amulet>=1.14.3,<2.0;python_version=='2.7'
+bundletester>=0.6.1,<1.0;python_version=='2.7'
+python-ceilometerclient>=1.5.0
+python-cinderclient>=1.4.0,<5.0.0
+python-glanceclient>=1.1.0
+python-heatclient>=0.8.0
+python-keystoneclient>=1.7.1
+python-neutronclient>=3.1.0
+python-novaclient>=2.30.1
+python-openstackclient>=1.7.0
+python-swiftclient>=2.6.0
+pika>=0.10.0,<1.0
+distro-info
+git+https://github.com/juju/charm-helpers.git#egg=charmhelpers
+# END: Amulet OpenStack Charm Helper Requirements
+# NOTE: workaround for 14.04 pip/tox
+pytz
+pyudev  # for ceph-* charm unit tests (not mocked?)

unit_tests/test_actions.py

@@ -48,17 +48,27 @@ class ResumeTestCase(CharmTestCase):
 class CompleteClusterSeriesUpgrade(CharmTestCase):
 
     def setUp(self):
+        to_patch = [
+            "is_leader",
+            "config_changed",
+            "leader_set",
+            "relation_ids",
+            "relation_set"]
         super(CompleteClusterSeriesUpgrade, self).setUp(
-            actions, ["config_changed", "is_leader", "leader_set"])
+            actions, to_patch)
 
     def test_leader_complete_series_upgrade(self):
         self.is_leader.return_value = True
 
+        self.relation_ids.return_value = ['relid:1']
         calls = [mock.call(cluster_series_upgrading=""),
                  mock.call(cluster_series_upgrade_leader="")]
         actions.complete_cluster_series_upgrade([])
         self.leader_set.assert_has_calls(calls)
         self.config_changed.assert_called_once_with()
+        self.relation_set.assert_called_once_with(
+            relation_id='relid:1',
+            relation_settings={'cluster-series-upgrading': None})
 
     def test_non_leader_complete_series_upgrade(self):
         self.is_leader.return_value = False

unit_tests/test_percona_hooks.py

@@ -619,6 +619,48 @@ class TestInstallPerconaXtraDB(CharmTestCase):
         self.run_mysql_checks.assert_not_called()
 
 
+class TestSeriesUpgrade(CharmTestCase):
+    TO_PATCH = [
+        'register_configs',
+        'pause_unit_helper',
+        'set_unit_upgrading',
+        'leader_get',
+        'leader_set',
+        'relation_ids',
+        'relation_set',
+        'get_relation_ip',
+        'render_config',
+    ]
+
+    def setUp(self):
+        CharmTestCase.setUp(self, hooks, self.TO_PATCH)
+
+    def test_prepare_leader(self):
+        self.register_configs.return_value = 'registered_configs'
+        self.leader_get.return_value = None
+        self.get_relation_ip.return_value = '10.0.0.10'
+        self.relation_ids.return_value = ['relid:1']
+        hooks.prepare()
+        self.pause_unit_helper.assert_called_once_with('registered_configs')
+        self.set_unit_upgrading.assert_called_once_with()
+        leader_set_calls = [
+            mock.call(cluster_series_upgrading=True),
+            mock.call(cluster_series_upgrade_leader='10.0.0.10')]
+        self.leader_set.assert_has_calls(leader_set_calls)
+        self.relation_set.assert_called_once_with(
+            relation_id='relid:1',
+            relation_settings={'cluster-series-upgrading': True})
+        self.render_config.assert_called_once_with([])
+
+    def test_prepare_non_leader(self):
+        self.register_configs.return_value = 'registered_configs'
+        self.leader_get.return_value = '10.0.0.10'
+        hooks.prepare()
+        self.pause_unit_helper.assert_called_once_with('registered_configs')
+        self.set_unit_upgrading.assert_called_once_with()
+        self.render_config.assert_called_once_with(['10.0.0.10'])
+
+
 class TestUpgradeCharm(CharmTestCase):
     TO_PATCH = [
         'config',