rpc.cleanup method is not reachable due to wrong import of rpc module

[Abhijeet Malawade]

In nova service rpc.cleanup method is not getting called because 'rpc' is not imported properly.

rpc = importutils.try_import('nova.openstack.common.rpc')
It should be
rpc = importutils.try_import('nova.rpc')

'rpc' module is not present in nova/openstack/common package.
As it is present in nova package it should be imported from there only.

Also rpc cleanup method should not be called while restarting the service as ideally cleanup task should be done only while exiting from the service. In case of SIGHUP signal, service gets restarted and tries to cleanup the rpc.

[Ben Nemec (bnemec)]

This is not a bug in Oslo AFAICT. It sounds like an Oslo rpc reference wasn't cleaned up in Nova when it converted to oslo.messaging. I'm not even sure where this bad import is happening (it would be good to link to the file where you see this), but it's likely that something needs to be imported from oslo.messaging.

[Abhijeet Malawade (abhijeet-malawade)]

Hi Ben,

Here is the nova service file where it is trying to import 'rpc' module from openstack common package.
https://github.com/openstack/nova/blob/master/nova/openstack/common/service.py#L48

Also same thing is happening in cinder. In cinder also it is trying to import 'rpc' module from
openstack comman packge, but 'rpc' module is present in cinder package.
https://github.com/openstack/cinder/blob/master/cinder/openstack/common/service.py#L47

Because of this I taught that we fix this in oslo-incubator and then sync to specific projects.

[Ben Nemec (bnemec)]

Ah, okay, then that is a bug in Oslo. We will need to fix service.py to use either rpc or oslo.messaging, depending on which is available. Another similar change was recently merged, and something like that should work here too: https://github.com/openstack/oslo-incubator/commit/109e325eec054aefe4fcef4b928a46a6d7247e05

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/103049

[Doug Hellmann (doug-hellmann)]

Some discussion on the dev mailing list about the right way to fix this: http://lists.openstack.org/pipermail/openstack-dev/2014-August/thread.html#41828