The HTTPRequest class in the tornado* web framework helpfully maps GET and POST arguments to lists. I understand why -- in case a given argument name is used multiple times. But for some RequestHandlers, this is a pain. For instance, if I want to pass a json object and parse it as-is on the server.
What's the most straightforward way to disable the map-to-list behavior so that I can send unaltered json to a tornado/cyclone server?
*Cyclone, actually, in case there's an implementation difference here.
Instead of accessing self.request.arguments directly you should use the accessor functions:
self.get_argument("ID", default=None, strip=False)
This returns a single item.
If you want to turn the arguments into a JSON object you can quite easily do so:
json.dumps({ k: self.get_argument(k) for k in self.request.arguments })