Question

My goal is to define a RESTful api using CherryPy (wsgi) + uWSGI + Nginx. I’m wondering how to handle the OPTIONS method, as suggested to me on #python. I was advised that implementing a handler to this method would help the callers to my api to understand what methods are supported, and what methods aren’t.

Here’s what I’ve got so far:

#!/usr/bin/env python

import cherrypy

# modules used for data access
import nosql
import dao

class Product(object):

    exposed = True

    def GET(self, key, *args, **kwargs):
        try:
            p = Product(nosql.get(key))
            return p.json
        except:
            # return 500 error with traceback if debug
            pass

    def POST(self, *args, **kwargs):
        try:
            p = dao.Product(*args, **kwargs)
            k = nosql.generate_key(Product.__name__)
            nosql.set(k,str(p))
        except:
            # return 500 error with traceback if debug
            pass

    def OPTIONS(self, *args, **kwargs):
        """
        The question is, what to return here?  I'm looking 
        at the following rfc:

        http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html
        """
        return "GET, POST"

conf = {
    '/': {
        'request.dispatch':cherrypy.dispatch.MethodDispatcher(),
    },
}

application = cherrypy.tree.mount(Product, config=conf)

Answer 1

The body of the OPTIONS response is not as important, and certainly not as specified, as the headers. As you mention, most clients are really only interested in the methods. Those are specified in the “Allow” response header, which CherryPy helpfully emits automatically when you use the MethodDispatcher. Anything else you might return is really up to you to try to meet the needs of the client’s application.