Question

I’m using jQuery’s AJAX function, like so:

$.ajax ({ "url" : "/note",
         "async" : true,
         "type" : "POST",
         "data" : {"id" : id, "content" : el.value}
       });

On the backend (Python Google App Engine, currently using webapp.RequestHandler), PUT requests are handled by the same function that handles POST requests, like so:

class uNote(webapp.RequestHandler):
def post(self):
    user = users.get_current_user()
    if user:
        logging.critical("ID: " + self.request.get('id'))
        note = stickynote.db.get( self.request.get('id') )
        if note:
            content = self.request.get( 'content' )
            if content:
                note.content = content
            else:
                note.x = int(self.request.get('x'))
                note.y = int(self.request.get('y'))
                note.z = int(self.request.get('z'))
            note.put()
            self.response.out.write ( "true" );
        else:
            self.response.out.write ("no id found")

def put(self):
    user = users.get_current_user()
    if user:
        logging.critical("ID: " + self.request.get('id'))
        note = stickynote.db.get( self.request.get('id') )
        if note:
            content = self.request.get( 'content' )
            if content:
                note.content = content
            else:
                note.x = int(self.request.get('x'))
                note.y = int(self.request.get('y'))
                note.z = int(self.request.get('z'))
            note.put()
            self.response.out.write ( "true" );
        else:
            self.response.out.write ("no id found")

If I make a POST request everything works. If I change it to a PUT request (by changing type of the AJAX call), nothing works. If I check the logs for GAE, I see:

BadKeyError: Invalid string key .

This is the result of me logging the ID for each call:

ID: ahFkZXZ-YXp2ZC13ZWJub3Rlc3ItCxIKU3RpY2t5Tm90ZSIQdGVzdEBleGFtcGxlLmNvbQwLEgdzbk1vZGVsGAIM (from the POST call)
ID: (from the PUT call)

So clearly it’s not passing the ID properly for PUT calls, which is why the datastore is giving me a BadKeyError. I’m not sure if this is a problem on jQuery’s side, or if it’s from GAE’s side, though, and I have no idea what’s going on. Any help would be appreciated.

Answer 1

self.request.POST, and hence self.request.get() don’t return form data for PUT requests (or any non-POST requests). While it’s not usual to submit form data using a PUT request (more commonly, you’re submitting something as the body of the request), it’s certainly a little odd that they’re deliberately disabling it here.

If you want to access the data, you’ll need to decode it from the body yourself, either using urlparse.parse_qs(self.request.body), or like this.

Another option would be to modify your API so you’re not using form data – for instance, by making the ID part of the URL, and send the content as the raw body of the PUT request.