HorizonMiddleware class causes excessive session rewrites and possible race condition resulting in logouts

[Eric Peterson]

the horizon middleware is checking for timestamps and modifying last_activity for nearly every request.... this is bad in the case of ajax requests for a couple of reasons...

A) ajax requests can be an order or magnitude greater than regular requests.... making the session backend get thrashed.

II) if you try to switch project context from a page where you have several longer running ajax requests going on, it is possible the longer running ajax requests will update your session with older tokens. The user will seem to be logged out at this point, and really frustrated.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/57963

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/57963
Committed: https://git.openstack.org/cgit/openstack/horizon/commit/?id=1b5fb743e23d8d0e22b7c6c11e4f29f36295f413
Submitter: Jenkins
Branch: master

commit 1b5fb743e23d8d0e22b7c6c11e4f29f36295f413
Author: ericpeterson-l <email address hidden>
Date: Fri Nov 22 08:54:39 2013 -0700

    Fix excessive ajax session thrash

    HorizonMiddleware causes excessive session rewrites
    and possible race condition resulting in logouts
    for ajax requests

    Change-Id: I1e1181a0830e23d43bfcf89729b9a98f6aaad965
    Closes-bug: #1253829