timeout logic causes logout when load balanced

[David Lyle]

The session timeout code in the horizon/middleware.py can cause inappropriate timeouts/logouts when running Horizon behind a load balancer on two machines that are slightly out of sync time-wise.

Results in redirection to the login screen and Session expired error if not fixed.

Example with 3 minute time difference:
  import datetime

  timestamp = datetime.datetime.now()

  day_one = datetime.datetime(2007, 12, 5, 9, 1, 1)
  day_two = datetime.datetime(2007, 12, 5, 9, 5, 1)

  print (day_one - day_two).seconds
  print (day_two - day_one).seconds

  print abs((day_one - day_two).total_seconds()) // apparently no total_seconds in python 2.6
  print abs((day_two - day_one).total_seconds())

  print abs(day_one - day_two).seconds
  print abs(day_two - day_one).seconds

Output:
  86160
  240
  240.0
  240.0
  240
  240

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/53163

[David Lyle (david-lyle)]

This was fixed in a commit for the bp django 1.6 support.

https://review.openstack.org/#/c/58947/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/havana
Review: https://review.openstack.org/66253

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/havana
Review: https://review.openstack.org/70016