Merge lp:~seyeongkim/charms/trusty/cinder/lp1383801 into lp:~openstack-charmers-archive/charms/trusty/cinder/next

[Seyeong Kim]

add restarting cinder-volume service on config-changed hook

[uosci-testing-bot (uosci-testing-bot)]

charm_lint_check #7127 cinder-next for xtrusia mp266176
    LINT OK: passed

Build: http://10.245.162.77:8080/job/charm_lint_check/7127/

[uosci-testing-bot (uosci-testing-bot)]

charm_unit_test #6622 cinder-next for xtrusia mp266176
    UNIT OK: passed

Build: http://10.245.162.77:8080/job/charm_unit_test/6622/

[Billy Olsen (billy-olsen)]

Adding a service_restart will guarantee that the service gets restarted whenever juju feels the urge to run the config_changed hook, which at the minimum per documentation (https://jujucharms.com/docs/devel/authors-charm-hooks#config-changed) includes:

- after install
- after upgrade charm
- after an agent is restarted
- whenever a configuration value is changed

And not in the documentation but also:
- whenever an agent loses connection with the state server(s)
- whenever a juju backup is created
- whenever else juju feels like it should

The config-changed hook should be expected to be invoked frequently. As such, restarting the cinder service every time will be disruptive.

We may need to see if we can further isolate this scenario a bit -or- use the underlying framework to detect if the value has changed (there is _some_ support in charmhelpers code, but I've little and less experience using it - see charmhelpers/core/unitdata.py iirc).

review: Needs Fixing

[lp:~seyeongkim/charms/trusty/cinder/lp1383801]

111. By Seyeong Kim on 2015-07-30

add condition for avoiding multiple restart

112. By Seyeong Kim on 2015-07-30

add unit test

113. By Seyeong Kim on 2015-07-30

fix lint error

Unmerged revisions

=== modified file 'hooks/cinder_hooks.py'
--- hooks/cinder_hooks.py	2015-07-21 19:28:23 +0000
+++ hooks/cinder_hooks.py	2015-07-30 03:03:36 +0000
@@ -144,6 +144,9 @@
                              upgrade_nonce=uuid.uuid4())
 
     CONFIGS.write_all()
+    # overwrite config is not in conf file. so We can't use restart_on_change
+    if config_value_changed('overwrite'):
+        service_restart('cinder-volume')
     configure_https()
     update_nrpe_config()