How to access jQuery in HTML 5 web worker

Question

I am unable to to access jQuery inside an HTML5 web worker. Is there a way I can do that?

Answer 1

tl;dr: include this script before jQuery

JQuery initally accesses lots of document properties to check for browser features. document is not defined in Worker and you actually cannot create Document instance in web workers at this moment. JQuery isn't prepared for that - as you could see in comments on your question, nobody seems to understand what would you do with JQuery without DOM.

Since, as I said, JQuery needs document to initialise, I created a dummy fake document object. This object acts as real document during JQuery tests:

var document = self.document = {parentNode: null, nodeType: 9, toString: function() {return "FakeDocument"}}; var window = self.window = self; var fakeElement = Object.create(document); fakeElement.nodeType = 1; fakeElement.toString=function() {return "FakeElement"}; fakeElement.parentNode = fakeElement.firstChild = fakeElement.lastChild = fakeElement; fakeElement.ownerDocument = document;  document.head = document.body = fakeElement; document.ownerDocument = document.documentElement = document; document.getElementById = document.createElement = function() {return fakeElement;}; document.createDocumentFragment = function() {return this;}; document.getElementsByTagName = document.getElementsByClassName = function() {return [fakeElement];}; document.getAttribute = document.setAttribute = document.removeChild =    document.addEventListener = document.removeEventListener =    function() {return null;}; document.cloneNode = document.appendChild = function() {return this;}; document.appendChild = function(child) {return child;}; 

Beware that this fake document is only meant to allow jQuery to load, it won't allow any real DOM operations.

Example usage:

importScripts("workerFakeDOM.js"); importScripts('jquery-2.1.4.min.js'); console.log("JQuery version:", $.fn.jquery); 

Test script

Allows you to try various versions of JQuery with my script.

JSfiddle

Check that you're using http://, my domain doesn't work with https://.

Download as script

Answer 2

The answer of Tomáš Zato was correct, but no longer works with newer jQuery version. I added some more for jQuery 3.1.1:

var document = self.document = { parentNode: null, nodeType: 9, toString: function () { return "FakeDocument" } }; var window = self.window = self; var fakeElement = Object.create(document); fakeElement.nodeType = 1; fakeElement.toString = function () { return "FakeElement" }; fakeElement.parentNode = fakeElement.firstChild = fakeElement.lastChild = fakeElement; fakeElement.ownerDocument = document;  document.head = document.body = fakeElement; document.ownerDocument = document.documentElement = document; document.getElementById = document.createElement = function () { return fakeElement; }; document.createDocumentFragment = function () { return this; }; document.getElementsByTagName = document.getElementsByClassName = function () { return [fakeElement]; }; document.getAttribute = document.setAttribute = document.removeChild =     document.addEventListener = document.removeEventListener =     function () { return null; }; document.cloneNode = document.appendChild = function () { return this; }; document.appendChild = function (child) { return child; }; document.childNodes = []; document.implementation = {     createHTMLDocument: function () { return document; } }