http - Firefox exception 'JavaScript component does not have a method named: "available"'

Question

I'm building a web app with Django. I have a bunch of API calls in Javascript via Ajax (jQuery v1.8.3).

Most of them work, but a particular one results in a return object with status 0 and this message as the statusText:

[Exception... "'JavaScript component does not have a method named: "available"' when calling method: [nsIInputStream::available]" nsresult: "0x80570030 (NS_ERROR_XPC_JSOBJECT_HAS_NO_FUNCTION_NAMED)" location: "JS frame :: http://127.0.0.1:8000/media/js/jquery.js :: .send :: line 8434" data: no]

The corresponding line in jQuery is xhr.send( ( s.hasContent && s.data ) || null );

However, this occurs only in Firefox. Chrome works fine. Again, other requests do work. The only thing which sets this one apart is the DELETE http method.

The request is as follow (HTTP network data shown in Chrome – Firebug doesn't show anything in Firefox):

Request URL: http://127.0.0.1:8000/api/reservation/13/
Request Method: DELETE
Status Code: 400 BAD REQUEST    (This is expected)

Request Headers
Accept: application/json, text/javascript, */*; q=0.01
Content-Length: 15
Content-Type: application/json
Origin: http://127.0.0.1:8000
Referer: http://127.0.0.1:8000/reservation/
X-Requested-With: XMLHttpRequest

Request Payload
[object Object]

Response Headers
Cache-Control: no-cache
Content-Type: text/html; charset=utf-8
Date: Tue, 02 Apr 2013 19:18:35 GMT
Server: WSGIServer/0.1 Python/2.7.2

On the server, I don't receive any request.

The JS code is (taken directly from Firebug Watch at breakpoint):

options = {
    contentType: "application/json",
    data: Object {},
    dataType: "json",
    processData: false,
    type: "DELETE",
    url: "/api/reservation/13/",
    error: function(),
    success: function()
};
$.ajax(options);

I also did try to disable all extensions in FF. I run v20.0.

Answer 1

The problem was a combination of Firefox with jQuery/XMLHttpRequest and sending an object via HTTP DELETE. Once JSON'ifying the object via JSON.stringify() everything worked.

Still, a strange exception for Firefox to throw.

Thanks to freddyb for that idea.