letmein/rack-middleware-json-parser — pull request #4 by wkoffel (2014-08-27 14:05:39+00:00)
Title: handle case where content-type is not specified in the request

I believe the behavior if the requestor doesn't specify a content-type is that this middleware shouldn't be active. Right now, it throws an error `undefined method include? for nil:NilClass` if a content-type header isn't set.

Notably, a regular GET request from a browser will trigger this, so it's a common pattern.