Error while loading config file

[Samriddhi]

While including a config file in keystone using the following[0], I'm getting this error[1],

[0]
.. show-options::
   :config-file: config-generator/keystone.conf

[1]
loading config file config-generator/keystone.conf

Exception occurred:
  File "/home/riddle/keystone/.tox/docs/lib/python3.5/site-packages/oslo_config/sphinxext.py", line 233, in _format_option_help
    for group_name, group_opts in sorted(by_section.items()):
TypeError: unorderable types: NoneType() < str()

[Doug Hellmann (doug-hellmann)]

I think the underlying cause for this bug has to do with building the documentation under python 3 instead of python 2. We need to make oslo.config work in this situation under python 3.

The values being sorted are the group names and options returned from the config generator's option discovery code. The None value causes the options to be placed in the group "DEFAULT". We should look into whether we can make the discovery code use "DEFAULT" instead of None, or if that would break other parts of the configuration generator (we may be relying on None as a sentinel value).

[Doug Hellmann (doug-hellmann)]

https://review.openstack.org/#/c/487108