Listen for volume.delete.start instead of end

Fixes bug 1057462

Register interest in volume.delete.start events instead of
volume.delete.end so that the owner isn't charged for time
taken to tear down the volume.

Change-Id: Idf27876aff8a3ccb2a6f76679744c8513783d523

ceilometer/volume/notifications.py

@@ -38,7 +38,7 @@ class _Base(plugin.NotificationBase):
     def get_event_types():
         return ['volume.exists',
                 'volume.create.end',
-                'volume.delete.end',
+                'volume.delete.start',
         ]
 
 

tests/volume/test_notifications.py

@@ -37,7 +37,7 @@ NOTIFICATION_VOLUME_DELETE = {
     u'_context_roles': [u'Member', u'admin'],
     u'_context_request_id': u'req-6ba8ccb4-1093-4a39-b029-adfaa3fc7ceb',
     u'_context_quota_class': None,
-    u'event_type': u'volume.delete.end',
+    u'event_type': u'volume.delete.start',
     u'timestamp': u'2012-09-21 10:24:13.168630',
     u'message_id': u'f6e6bc1f-fcd5-41e1-9a86-da7d024f03d9',
     u'_context_auth_token': u'277c6899de8a4b3d999f3e2e4c0915ff',