XML middleware will try to convert everything even if it's not json

[Jamie Lennox]

There are certain routes like /v2.0/certificates/ca that return PEM files that do not return the standard choice of JSON or XML data. If you request these routes with XML in the Accept field (like if you hit it with a browser) then the XML middleware will kick in and assume that, like other requests, it needs to load it as json then convert it to xml.

This is obviously wrong. We should only be doing XML processing if we understand the content we are trying to convert, and it is better to return something that is not on the Accept list than return an error (in JSON no less).

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/62809

[Dolph Mathews (dolph)]

Code review is long abandoned.

[David Stanek (dstanek)]

The XML middleware has been marked as deprecated so I don't see a lot of work happening here.