public/remote.html

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset=utf-8 />
  <title>remote</title>
</head>

<body>
  <script src="/js/EventSource.js"></script>
  <script>
    /* jshint browser:true */
    var id = window.location.search.replace(/.*\?/, '');
    var origin = null;
    window.addEventListener('message', function (event) {
      origin = event.origin;
      if (event.data === '__init__' || typeof event.data !== 'string') {
        return;
      }
      var xhr = new XMLHttpRequest();
      var params = 'data=' + encodeURIComponent(event.data);
      xhr.open('POST', '/remote/' + id + '/log', true);
      xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
      xhr.send(params);
    }, false);
    setTimeout(function () {
      var sse = new EventSource('/remote/' + id + '/run');
      sse.onmessage = function (event) {
        window.top.postMessage(event.data, origin);
      };
    }, 13);

  </script>
</body>

</html>