Tooltron

window.onload = function() {

  var rfid = document.getElementById("rfid");

  var button = document.getElementById("refresh");

  var errors = document.getElementById("errors");

  button.onclick = function() {

    var req = new XMLHttpRequest();

    req.open("GET", "/get-rfid", true);

    req.send();

    req.onreadystatechange = function() {

      if (req.readyState == 4) {

        if (req.status == 200) {

          rfid.value = req.responseText.replace(/\s/g, '');

          errors.innerText = '';

        } else {

          errors.innerText = 'Error '+req.status+'\n'+req.responseText;

        }

      }

    };

  };

  button.onclick();

};