Adding upgrade action and associated configs & unit tests to cinder charm.

actions.yaml

@@ -1,2 +1,4 @@
 git-reinstall:
   description: Reinstall cinder from the openstack-origin-git repositories.
+openstack-upgrade:
+  description: Perform openstack upgrades. Config option action-managed-upgrade must be set to True.

config.yaml

@@ -282,4 +282,13 @@ options:
     description: |
       A comma-separated list of nagios servicegroups.
       If left empty, the nagios_context will be used as the servicegroup
-
+  action-managed-upgrade:
+    default: False
+    type: boolean
+    description: |
+      If True enables openstack upgrades for this charm via juju actions.
+      You will still need to set the config variable for the openstack version
+      but instead of an upgrade running automatically across all units, it will
+      wait for you to execute the openstack-upgrade action for this charm on each
+      unit. If False it will revert to existing behavior of upgrading all units on
+      config change.

hooks/cinder_hooks.py

@@ -141,7 +141,7 @@ def config_changed():
     if git_install_requested():
         if config_value_changed('openstack-origin-git'):
             git_install(config('openstack-origin-git'))
-    else:
+    elif not config('action-managed-upgrade'):
         if openstack_upgrade_available('cinder-common'):
             do_openstack_upgrade(configs=CONFIGS)
             # NOTE(jamespage) tell any storage-backends we just upgraded