JavaScript async remote

gistfile1

(function (window, document) {

    var settings = {
        dataId: 'data-myModule-id',
        url: '/api/mymodule/'
    };

    function load() {
        var elems = document.querySelectorAll('[' + settings.dataId + ']');
        if (!elems) {
            return;
        }
        for (var i = 0; i < elems.length; i++) {
            var target = elems[i],
                id = target.getAttribute(settings.dataId);
            if (!id) {
                continue;
            }
            get(settings.url + id, function (response) {
                if (!response.harTilmelding) {
                    return;
                }
                var btn = document.createElement('button'),
                    txt = document.createTextNode(response.tekst);
                btn.appendChild(txt);
                btn.onclick = function () {
                    location.href = response.url;
                };
                target.appendChild(btn);
            });
        }
    }

    function get(url, success) {
        var xmlhttp;
        if (window.XMLHttpRequest) { // code for IE7+, Firefox, Chrome, Opera, Safari
            xmlhttp = new XMLHttpRequest();
        } else { // code for IE6, IE5
            xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
        }
        xmlhttp.onreadystatechange = function () {
            if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
                success(JSON.parse(xmlhttp.responseText));
            }
        };
        xmlhttp.open("GET", url, true);
        xmlhttp.send();
    }

    window.onload = load;

})(window, document);