Series Upgrade

Implement the series-upgrade feature allowing to move between Ubuntu
series.

Change-Id: Ia4a4f0eb9f20780560f0244f3070cc6670d700c8

charmhelpers/contrib/openstack/utils.py

@@ -186,7 +186,7 @@ SWIFT_CODENAMES = OrderedDict([
     ('queens',
         ['2.16.0', '2.17.0']),
     ('rocky',
-        ['2.18.0']),
+        ['2.18.0', '2.19.0']),
 ])
 
 # >= Liberty version->codename mapping
@@ -1733,3 +1733,21 @@ def is_unit_upgrading_set():
             return not(not(kv.get('unit-upgrading')))
     except Exception:
         return False
+
+
+def series_upgrade_prepare(pause_unit_helper=None, configs=None):
+    """ Run common series upgrade prepare tasks."""
+    set_unit_upgrading()
+    if pause_unit_helper and configs:
+        if not is_unit_paused_set():
+            pause_unit_helper(configs)
+
+
+def series_upgrade_complete(resume_unit_helper=None, configs=None):
+    """ Run common series upgrade complete tasks."""
+    clear_unit_paused()
+    clear_unit_upgrading()
+    if configs:
+        configs.write_all()
+        if resume_unit_helper:
+            resume_unit_helper(configs)

hooks/glance_relations.py

@@ -54,6 +54,8 @@ from glance_utils import (
     reinstall_paste_ini,
     is_api_ready,
     update_image_location_policy,
+    pause_unit_helper,
+    resume_unit_helper,
 )
 from charmhelpers.core.hookenv import (
     charm_dir,
@@ -101,6 +103,8 @@ from charmhelpers.contrib.openstack.utils import (
     pausable_restart_on_change as restart_on_change,
     is_unit_paused_set,
     os_requires_version,
+    series_upgrade_prepare,
+    series_upgrade_complete,
 )
 from charmhelpers.contrib.storage.linux.ceph import (
     send_request_if_needed,
@@ -618,6 +622,20 @@ def certs_changed(relation_id=None, unit=None):
     configure_https()
 
 
+@hooks.hook('pre-series-upgrade')
+def pre_series_upgrade():
+    juju_log("Running prepare series upgrade hook", "INFO")
+    series_upgrade_prepare(
+        pause_unit_helper, CONFIGS)
+
+
+@hooks.hook('post-series-upgrade')
+def post_series_upgrade():
+    juju_log("Running complete series upgrade hook", "INFO")
+    series_upgrade_complete(
+        resume_unit_helper, CONFIGS)
+
+
 if __name__ == '__main__':
     try:
         hooks.execute(sys.argv)

hooks/post-series-upgrade

@@ -0,0 +1 @@
+glance_relations.py

hooks/pre-series-upgrade

@@ -0,0 +1 @@
+glance_relations.py