firefox OS app,CORS in Firefox os app

Question

I have been developing web-app(not hosted app) in firefox OS . I want to access the websites xml/JSON data using XMLHttp request. but it gives error as CORS not allowed to access the data . I know about to add 'Access-Control-Allow-Origin' header in website and enabling CORS may cause security issues. But is their any alternate way to access the data feed via XMLHttp request?

Answer 1

First change your manifest to have the following fields (the type one gets forgotten by people):

"type": "privileged", 
"permissions": {
    "systemXHR" : {}
}

Second, move all your JavaScript code to a separate JS file. Because it's not allowed to have inline tags in a privileged application.

Third use the mozSystem constructor like raidendev said:

var xhr = new XMLHttpRequest({ mozSystem: true });

Answer 2

To perform cross-domain http request from Firefox OS app you need to set permission systemXHR in app's manifest:

 "permissions": {
     "systemXHR" : {}
 }

and create XMLHttpRequest with property mozSystem set to true:

var xhr = new XMLHttpRequest({ mozSystem: true });

Also, for any cases where XMLHttpRequest is not applicable, you can use TCP Socket API.

var socket = navigator.mozTCPSocket.open('localhost', 80);

socket.ondata = function (event) {
  if (typeof event.data === 'string') {
    console.log('Get a string: ' + event.data);
  } else {
    console.log('Get a Uint8Array');
  }
}