Redis driver claims failing in smoke test

[Kurt Griffiths]

When smoke-testing the redis driver via zaqar-bench, I noted this output which does not appear when running the same test against the mongo driver:

Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: A claim was specified, but the message is not currently claimed.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
Could not delete messages: This message is claimed; it cannot be deleted without a valid claim ID.
C

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/119978

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/119978
Committed: https://git.openstack.org/cgit/openstack/zaqar/commit/?id=22ea4d0a33db9ea068e16cef67936f96b5f5cce5
Submitter: Jenkins
Branch: master

commit 22ea4d0a33db9ea068e16cef67936f96b5f5cce5
Author: kgriffs <email address hidden>
Date: Mon Sep 8 22:00:46 2014 -0500

    Fix messages getting reclaimed in the Redis driver

    A race condition was discovered during smoke testing of the Redis
    driver that can cause messages to be reclaimed. The problem was that
    between getting a list of "active" messages, and setting watch on
    them, they could be claimed by another process without the first
    process being notified.

    This patch gaurds against the race condition by moving the query for
    active messages to execute after the watch has been set. In this way,
    if another process commits a claim in the meantime, the first process
    will be notified so that it can try again with a new batch of active
    messages.

    Change-Id: I27a7e88ef0c3f9f8b1c5e653caec0fc503905e13
    Closes-Bug: #1367033