MIME, someday, maybe*

In a properly REST application, the server should engage in content negotiation to deliver the client's preferred representation of a resource.

I would love to make it possible, within klein, to separate the reification of the resource (i.e. instantiation of a model object) from the serialization of that resource (i.e. invocation of a view).

For example: let's say we have an API, /foo, which is a JSON API that returns {"foo": "bar"}. However, the user might hit it in a web browser, where it might be more helpful to present this information via an HTML template (rendered, perhaps, via twisted.web.template).

I'd love to do something like this:

@something("/foo")
def foo(request, values):
    return {"foo": "bar"}

@foo.serializer("text/html")
def as_html(request, model):
    return someTemplate.fillSlots(**model)

@foo.serializer("application/json")
def as_json(request, model):
   return json.dumps(model)

Of course, serializing as JSON and HTML are probably two pretty common ones, so maybe there should be a less verbose way to set this up, simply a way to specify a template. I am not sure how this should look, I'd just like it to be easy. Also, this should be possible on inputs as well: you might want to accept parameters as either JSON or urlencoded key/value pairs.

*: With apologies to Marc Andreessen.

No files, tests, or entry points are named. Review Klein's existing routing and response handling, then define how resource reification, content negotiation, and serializers for HTML, JSON, and input formats should fit together.