AJAX helpers with jQuery

ajax.js

module.exports = new Ajax();

function Ajax() { };

Ajax.prototype.get = function (url, callback, error) {
  var req = this.makeRequest('GET', url, callback, error);
  req.send();
};

Ajax.prototype.post = function (url, data, callback, error) {
  var req = this.makeRequest('POST', url, callback, error);
  req.send(data);
};

Ajax.prototype.makeRequest = function (method, url, callback, error) {
  var req = new XMLHttpRequest();

  req.open(method, url, true);

  req.onreadystatechange = function () {
    if (req.readyState == 4 && req.status >= 200 && req.status < 400) {
      callback(req.responseText);
    }
    else if (error) {
      error();
    }
  };

  req.onerror = function () {
    if (error) error();
  };

  return req;
};