AJAX

ajax.js

var ajax = function(url, data) {
    var wrap = function(method, cb) {
        var xhr = new XMLHttpRequest();

        xhr.open(method, url, true);
        xhr.setRequestHeader('Content-Type', 'application/json');
        xhr.send(data ? JSON.stringify(data) : null);
        
        xhr.onreadystatechange = function() {
            if (xhr.readyState == 4 && xhr.status > 0)
                cb(xhr);
        }

        return xhr;
    };

    return {
        get: function(cb) {
            return wrap('GET', cb);
        },
        post: function(cb) {
            return wrap('POST', cb);
        }
    };
};