How can I use jQuery in Greasemonkey scripts in Go

Question

As some of you may know, Google Chrome has put some severe limitation on Greasemonkey scripts.

Chromium does not support @require, @resource, unsafeWindow, GM_registerMenuCommand, GM_setValue, or GM_getValue.

Without require, I can't find a way to include the jQuery library in Greasemonkey script under Google Chrome.

Does anybody have some advice in this matter?

Answer 1

Use jQuery without fear of conflicts, by calling jQuery.noConflict(true). Like so:

function GM_main ($) {
    alert ('jQuery is installed with no conflicts! The version is: ' + $.fn.jquery);
}

add_jQuery (GM_main, "1.7.2");

function add_jQuery (callbackFn, jqVersion) {
    jqVersion       = jqVersion || "1.7.2";
    var D           = document;
    var targ        = D.getElementsByTagName ('head')[0] || D.body || D.documentElement;
    var scriptNode  = D.createElement ('script');
    scriptNode.src  = 'http://ajax.googleapis.com/ajax/libs/jquery/'
                    + jqVersion
                    + '/jquery.min.js'
                    ;
    scriptNode.addEventListener ("load", function () {
        var scriptNode          = D.createElement ("script");
        scriptNode.textContent  =
            'var gm_jQuery  = jQuery.noConflict (true);\n'
            + '(' + callbackFn.toString () + ')(gm_jQuery);'
        ;
        targ.appendChild (scriptNode);
    }, false);
    targ.appendChild (scriptNode);
}

---

---

But, For cross-browser scripts, why not take advantage of a nice, fast, local copy of jQuery, when you can?

The following works as a Chrome userscript and a Greasemonkey script, and it uses the nice local @require copy of jQuery, if the platform supports it.

// ==UserScript==
// @name     _Smart, cross-browser jquery-using script
// @include  http://YOUR_SERVER.COM/YOUR_PATH/*
// @require  http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js
// @grant    GM_info
// ==/UserScript==

function GM_main ($) {
    alert ('jQuery is installed with no conflicts! The version is: ' + $.fn.jquery);
}

if (typeof jQuery === "function") {
    console.log ("Running with local copy of jQuery!");
    GM_main (jQuery);
}
else {
    console.log ("fetching jQuery from some 3rd-party server.");
    add_jQuery (GM_main, "1.7.2");
}

function add_jQuery (callbackFn, jqVersion) {
    var jqVersion   = jqVersion || "1.7.2";
    var D           = document;
    var targ        = D.getElementsByTagName ('head')[0] || D.body || D.documentElement;
    var scriptNode  = D.createElement ('script');
    scriptNode.src  = 'http://ajax.googleapis.com/ajax/libs/jquery/'
                    + jqVersion
                    + '/jquery.min.js'
                    ;
    scriptNode.addEventListener ("load", function () {
        var scriptNode          = D.createElement ("script");
        scriptNode.textContent  =
            'var gm_jQuery  = jQuery.noConflict (true);\n'
            + '(' + callbackFn.toString () + ')(gm_jQuery);'
        ;
        targ.appendChild (scriptNode);
    }, false);
    targ.appendChild (scriptNode);
}

Answer 2

Easier solution: cut+paste the contents of jquery.min.js into the top of your user script. Done.

I found various problems with the recommended answers. The addJQuery() solution works on most pages but has bugs on many. If you run into issues just copy+paste the jquery contents into your script.

Answer 3

There's a really easy way to get around including a full copy of jQuery for Chrome scripts when those scripts don't actually use any privileged features (GM_* functions, etc)...

Simply insert the script itself into the page DOM and execute! The best part is that this technique works just as well on Firefox+Greasemonkey, so you can use the same script for both:

var script = document.createElement("script");
script.type = "text/javascript";
script.textContent = "(" + threadComments.toString() + ")(jQuery)";
document.body.appendChild(script);

function threadComments($) {
    // taken from kip's http://userscripts-mirror.org/scripts/review/62163
    var goodletters = Array('\u00c0','\u00c1','\u00c2','\u00c3','\u00c4','\u00c5','\u00c6','\u00c7'
                             ,'\u00c8','\u00c9','\u00ca','\u00cb','\u00cc','\u00cd','\u00ce','\u00cf'
                                      ,'\u00d1','\u00d2','\u00d3','\u00d4','\u00d5','\u00d6'         
                             ,'\u00d8','\u00d9','\u00da','\u00db','\u00dc','\u00dd'                  
                             ,'\u00e0','\u00e1','\u00e2','\u00e3','\u00e4','\u00e5','\u00e6','\u00e7'
                             ,'\u00e8','\u00e9','\u00ea','\u00eb','\u00ec','\u00ed','\u00ee','\u00ef'
                                      ,'\u00f1','\u00f2','\u00f3','\u00f4','\u00f5','\u00f6'         
                             ,'\u00f8','\u00f9','\u00fa','\u00fb','\u00fc','\u00fd'         ,'\u00ff').join('');

    // from Benjamin Dumke's http://userscripts-mirror.org/scripts/review/68252
    function goodify(s)
      {
         good = new RegExp("^[" + goodletters + "\\w]{3}");
         bad = new RegExp("[^" + goodletters + "\\w]");
         original = s;
         while (s.length >3 && !s.match(good)) {
            s = s.replace(bad, "");
            }
         if (!s.match(good))
         {
           // failed, so we might as well use the original
           s = original;
         }
         return s;
      }  

    in_reply_to = {};


    function who(c, other_way) {


        if (other_way)
        {
            // this is closer to the real @-reply heuristics
            m = /@(\S+)/.exec(c);
        }
        else
        {
            m = /@([^ .:!?,()[\]{}]+)/.exec(c);
        }
        if (!m) {return}
        if (other_way) {return goodify(m[1]).toLowerCase().slice(0,3);}
        else {return m[1].toLowerCase().slice(0,3);}
    }

    function matcher(user, other_way) {
        if (other_way)
        {
            return function () {
                return goodify($(this).find(".comment-user").text()).toLowerCase().slice(0,3) == user
                }
        }
        else
        {
            return function () {
                return $(this).find(".comment-user").text().toLowerCase().slice(0,3) == user
                }
        }
    }

    function replyfilter(id) {
        return function() {
            return in_reply_to[$(this).attr("id")] == id;
        }
    }

    function find_reference() {
        comment_text = $(this).find(".comment-text").text();
        if (who(comment_text))
        {
            fil = matcher(who(comment_text));
            all = $(this).prevAll("tr.comment").filter(fil);
            if (all.length == 0)
            {
                // no name matched, let's try harder
                fil = matcher(who(comment_text, true), true);
                all = $(this).prevAll("tr.comment").filter(fil);
                if (all.length == 0) {return}
            }
            reference_id = all.eq(0).attr("id");
            in_reply_to[$(this).attr("id")] = reference_id;
        }
    }


    // How far may comments be indented?
    // Note that MAX_NESTING = 3 means there are
    // up to *four* levels (including top-level)
    MAX_NESTING = 3

    // How many pixels of indentation per level?
    INDENT = 30

    function indenter(parent) {

        for (var i = MAX_NESTING; i > 0; i--)
        {
            if (parent.hasClass("threading-" + (i-1)) || (i == MAX_NESTING && parent.hasClass("threading-" + i)))
            {
                return function() {
                    $(this).addClass("threading-" + i).find(".comment-text").css({"padding-left": INDENT*i});
                }
            }
        }

        return function() {
            $(this).addClass("threading-1").find(".comment-text").css({"padding-left": INDENT});
        }

    }

    function do_threading(){
        id = $(this).attr("id");
        replies = $(this).nextAll("tr.comment").filter(replyfilter(id));
        ind = indenter($(this));
        replies.each(ind);
        replies.insertAfter(this);
    }

    function go() {
        $("tr.comment").each(find_reference);
        $("tr.comment").each(do_threading);
    }

    $.ajaxSetup({complete: go});
    go();
}

(unapologetically stolen from Shog9 on meta.stackoverflow since he didn't move it here, and I have to delete the meta post..)

Answer 4

I wonder if you couldn't rely on document.defaultView.jQuery in your GM script ala:

if (document.defaultView.jQuery) {
  jQueryLoaded(document.defaultView.jQuery);
} else {
  var jq = document.createElement('script');
  jq.src = 'http://jquery.com/src/jquery-latest.js';
  jq.type = 'text/javascript';
  document.getElementsByTagName('head')[0].appendChild(jq);
  (function() { 
    if (document.defaultView.jQuery) jQueryLoaded(document.defaultView.jQuery);
    else setTimeout(arguments.callee, 100);
  })();
}

function jQueryLoaded($) {
  console.dir($);
}

Answer 5

The simple way is using required keyword:

// @require     http://code.jquery.com/jquery-latest.js

Answer 6

Another approach would be to modify your script to load jQuery manually. Example from http://joanpiedra.com/jquery/greasemonkey/:

// Add jQuery
var GM_JQ = document.createElement('script');
GM_JQ.src = 'http://jquery.com/src/jquery-latest.js';
GM_JQ.type = 'text/javascript';
document.getElementsByTagName('head')[0].appendChild(GM_JQ);

// Check if jQuery's loaded
function GM_wait() {
    if(typeof unsafeWindow.jQuery == 'undefined') { window.setTimeout(GM_wait,100); }
else { $ = unsafeWindow.jQuery; letsJQuery(); }
}
GM_wait();

// All your GM code must be inside this function
function letsJQuery() {
    alert($); // check if the dollar (jquery) function works
}

EDIT: DRATS! After testing it appears this code does not work since Google Chrome runs userscripts/extensions in a separate scope/process from the actual webpage. You can download the jQuery code using an XmlhttpRequest and then Eval it, but you have to host the code on a server that allows Cross-Origin Resource Sharing using the Access-Control-Allow-Origin: * header. Sadly NONE of the current CDNs with jQuery support this.