Comment 2 for bug 967887

Reviewed: https://review.openstack.org/5938
Committed: http://github.com/openstack/glance/commit/0dc093b98faf8e256ddc48f9dafb4d061662f0e3
Submitter: Jenkins
Branch: master

commit 0dc093b98faf8e256ddc48f9dafb4d061662f0e3
Author: Adam Gandelman <email address hidden>
Date: Wed Mar 28 17:08:13 2012 -0700

    Add MySQLPingListener() back

    The use of wrap_db() to catch low-level problems in the connection
    pool appears to be incompatible with new versions of sqlalchemy
    (0.7.4/precise). This re-instates the use of a event listener to
    catch the error of 'mysql has gone away'. Keeps the wrapping
    logic in place for use before the connection pool has been constructed,
    specifically to allow glance to retry its initial database connection on
    service startup.

    Fixes bug 967887

    Change-Id: Ia732377d3404104b8acf7fe4ada164ec7ecf705f