Don't ask already authenticated users to log in

[Julie Pichon]

At the moment, we have a bit of an inconsistency in how we handle already logged in users:

1. Before authenticating, go to https://my_dashboard/ : you are asked to enter your username and password
2. After authenticating, return to https://my_dashboard/ : you are redirected to the overview page (user home page)

However, the login page itself behaves differently:

1. Before authenticating, go to https://my_dashboard/auth/login : you are asked to enter your username and password
2. After authenticating, return to https://my_dashboard/auth/login : you are asked again to enter your username and password

This is misleading some users into believing they can have multiple Horizon sessions open at once in different projects or even with different users. It then causes issues when creating new resources as they do not get added in the project that was expected.

I'd like to suggest performing the same redirect when accessing the /auth/login page to help reduce the user confusion around this.

[Openstack Gerrit (openstack-gerrit)]

Fix proposed to branch: master
Review: https://review.openstack.org/88019

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/88019
Committed: https://git.openstack.org/cgit/openstack/django_openstack_auth/commit/?id=ee41e31b9a2f98128d35ad4d76cb81e124fb46ea
Submitter: Jenkins
Branch: master

commit ee41e31b9a2f98128d35ad4d76cb81e124fb46ea
Author: Julie Pichon <email address hidden>
Date: Wed Apr 16 17:16:00 2014 +0100

    Redirect the user if they're already logged in

    Similar to when the domain root url is accessed, if the user is
    already logged in do not show them the login page nor ask for their
    credentials. This avoids users being misled into thinking they can
    open multiple sessions in parallel, and is in line with how most web
    applications handle this.

    Change-Id: Ibd37b9c488d65cf54b156f23db4fa04f019d8092
    Closes-Bug: #1308637