Preserve media type params in conneg

[alexanderkiel]

Currently in 0.6.0, media types from the accept header and :available-media-types are stripped down to pairs like ["text" "html"]. That pairs are used to compare acceptable types and so on.

I need to be able to specify media types with params like application/json;profile="urn:org.restfulobjects:homepage" in :available-media-types because that is my content type of the representation I like to return. You can find such media types in the Restful Objects Spec.

I already looked into the liberator.conneg namespace. But this wouldn't be a small patch. I think the namespace would benefit from a MediaType protocol and record. But I like to discuss this first.

[ordnungswidrig]

This sounds like a reasonable feature request.

For now you can specify a function for :media-type-available? like this:

((resource
  :media-type-available?
  (fn [ctx]
    (when-let [mt (some #{(get-in ctx [:request :headers "accept"])}
                      ["application/json;profile=a" "application/json;profile=b"])]
      {:representation {:media-type mt}}))
  :handle-ok #(str "This is a " (get-in % [:representation :media-type])))
 {:request-method :get :headers {"accept" "application/json;profile=a"}})

:media-type-available? expects a function that receives the context as argument and returns an updated context if a matching media type was found. In the context the media-type at :representation / :media-type. To fail the negotiation either return a falsy value or a vetctor [false, the-updated-context].