Logout of Geo secondary after logging out of primary: undefined method `[]' for nil:NilClass

Summary

If you logout out of a Geo secondary node after logging out of the Geo primary, you get an undefined method '[]' for nil:NilClass

Steps to reproduce

  1. Using Chrome, login to a Geo primary with the root account
  2. Open a tab in the same browser and login to the Geo secondary, using the same account
  3. Logout of the primary
  4. Logout of the secondary

You get a

NoMethodError at /oauth/geo/logout
undefined method `[]' for nil:NilClass

Screen_Shot_2018-01-03_at_10.20.47_AM

Possible fixes

Problem occurs here:

https://gitlab.com/gitlab-org/gitlab-ee/blob/master/ee/app/controllers/oauth/geo_auth_controller.rb#L37