alphagov/collections — pull request #46 by edds (2014-10-16 13:23:29+00:00)
Title: Explicitly enable public action request formats

Instead of throwing 500 errors for requests for formats that are not
supported, return a 406. Actions that need to respond to formats other
than html must now explicitly enable them using the
enable_request_format helper.

https://www.pivotaltracker.com/story/show/80724644