How can I use XMLHttpRequest from main.js in the sdk extension of Firefox add-ons. (or something similar)

Question

I have a Firefox extension that needs to be checked for the onUnload event. Basically I want to send a message to my server when the user disables the extension.

What I tried to do was send a message to one of my content scripts, which XMLHttpRequest then calls. This works great for any other event that triggers the extension, but it looks like content scripts will be unloaded before the message can even go through.

main.js

Here is the code from main.js script:

exports.onUnload = function(reason) {
    //unloadWorker comes from a PageMod 'onAttach: function(worker){}'
    //That is called every time a page loads, so it will a recent worker.
    if(unloadWorker != null) { 
        unloadWorker.port.emit("sendOnUnloadEvent", settings, reason);
    }
};

content script

Here is the code from the contents of the script that I attach to each page that loads.

self.port.on("sendOnUnloadEvent", function(settings, reason) {
    console.log("sending on unload event to servers");
    settings.subid = reason;
    if(reason != "shutdown") {
        sendEvent(("on_unload"), settings);
    }
});

Send event code

, , XMLHttpRequest:

sendEvent = function(eventName, settings) {

    if (!eventName) {
        eventName = "ping"; 
    }
    //Not the actual URL, but you get the idea.
    var url = 'http://example.com/sendData/?variables=value&var2=value2'

    var xhr = new XMLHttpRequest();
    xhr.onreadystatechange = function() {

    }

    xhr.open("GET", url, true);
    xhr.send();
}

XMLHttpRequest main.js?

, , onUnload, , ? ( beforeOnUnload)

Answer 1

main.js Request sdk/request.

Request , , .

sdk/net/xhr, XMLHttpRequest GET :

const {XMLHttpRequest} = require("sdk/net/xhr");
exports.onUnload = function(reason) {
    var url = 'http://mysite.com/sendData/?variables=value&var2=value2'
    var xhr = new XMLHttpRequest();
    xhr.open('GET', url, false);
    xhr.send(null);
});

, sdk/net/xhr , .

Answer 2

user2958125, .

const {Cc, Ci} = require("chrome");
var xhr = Cc["@mozilla.org/xmlextras/xmlhttprequest;1"].createInstance(Ci.nsIXMLHttpRequest);
//var xhr = Components.classes["@mozilla.org/xmlextras/xmlhttprequest;1"].createInstance(Components.interfaces.nsIXMLHttpRequest);

xhr.onreadystatechange = function() {

}

xhr.open("GET", url, true);
xhr.send();

Answer 3

function reqListener () {
  console.log(this.responseText);
}

const {XMLHttpRequest} = require("sdk/net/xhr");
var url = "http://ya.ru";
var xhr = new XMLHttpRequest();
xhr.onload = reqListener;
xhr.open('GET', url, false);
xhr.send(null);