Listener connections are not getting closed while restarting rpc server

[Abhijeet Malawade]

There are leaks in releasing amqp connections which are opened for
listening on topics by messaging servers. Here connections opened by
listeners are not being closed after stopping servers.

When service restart happens (after getting SIGHUP signal) it is
creating new listener and old listener is not getting closed.
Because of this messages are not processed properly.
Ideally listeners should be closed after all messages are completely processed before restarting rpc server.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/103186

[Abhijeet Malawade (abhijeet-malawade)]

When we send 'SIGHUP' signal to nova-compute service to reload configuration, connections opened by listeners are not being closed after stopping service. And on service restart it is creating new connections.
After stopping nova-compute service (messaging server), listener object is not garbage collected as it is still referenced by the connection object. We need to remove this cyclic reference to close listener connections.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/103186
Committed: https://git.openstack.org/cgit/openstack/oslo.messaging/commit/?id=f37800943e18edfa4754164772572b4caef18152
Submitter: Jenkins
Branch: master

commit f37800943e18edfa4754164772572b4caef18152
Author: Abhijeet Malawade <email address hidden>
Date: Fri Jun 27 07:29:57 2014 -0700

    Cleanup listener after stopping rpc server

    If you don't close the AMQP connection, then the connection
    remains open and the next time when the messages are sent on
    the listening topic, then some of the messages will not be processed
    as there is no dispatcher running to process the message.

    Closes-Bug: #1335086
    Change-Id: I1f39eedf1500b6b6209ae0222f32e08e304895e0