Subdomain tunneling with jQuery and document.domain

subdomain.js

/**
 * Replace $.ajax on your subdomain with a copy taken
 * from your base domain. All jQuery AJAX actions go
 * through $.ajax (i.e. $.get, $.post), so it's all good.
 */
(function() {
    var iframe,
        onload,
        queue = [],

    // This has to be set both here and in iframe.html
    document.domain = 'example.com';
    
    // Back up this page's copy of $.ajax
    window.$._ajax = window.$.ajax;

    // We'll first replace $.ajax with a thin wrapper that both
    // loads our iframe tunnel and saves invocations until the
    // iframe is ready

    $.ajax = function(params) {

        if (!iframe) {

            // tunnel.html should be a bare bones html page that
            // includes a copy of jQuery, and sets document.domain
            // to 'example.com'
            
            iframe = $('<iframe>')
                .attr('src', 'http://example.com/tunnel.html')
                .load(onload)
                .appendTo('head')[0];
        }

        // Save calls to $.ajax, execute when we're ready
        queue.push(params);
    };

    function onload() {
    
        // Our prize: a version of $.ajax that can communicate safely
        // with our base domain
        window.$.ajax = iframe.contentWindow.jQuery.ajax;

        // Flush queued $.ajax calls
        $.each(queue, function(_, params) {
            $.ajax(params);
        });

        queue = null;
    }
})();

I actually haven't used deferreds with this code, so I'm not familiar with the trouble you're having. Normally I'd poke around and figure it out, but I'm kind of swamped at the moment.

Thanks anyway. I can't seem to get this working in chrome. I'm stilling getting "Access-Control-Allow-Origin" errors. Does the iframe have to be served from the domain you're trying access?

Does the iframe have to be served from the domain you're trying access?

Yes, definitely. Did you read the original article? http://benv.ca/2011/3/7/subdomain-tunneling-with-jquery-and-document-domain/

yeah, sorry I mean sub-domain. But looks like no matter what I try, doing POST to the subdomain isn't going to work for me.

Since we're not using https I'll just switch to jsonp and GET.

I have it backwards, I have code on my primary domain, that needs to post to the subdomain.

IE doesn't seem to like this solution... Have you experienced any trouble using IE?