title: Respond multiple times to one request?
body: <p>One place in my rails app requires loading a number of responses from an external server, which currently looks like this:</p>
  
  <ol>
  <li>User makes an AJAX request to the server. "Loading data..." is displayed.</li>
  <li>5-30 seconds later, the rails app sends response (assuming the data has not been cached).</li>
  </ol>
  
  <p>It would be much better if I could keep the user informed during that long waiting period with messages informing them of the progress of the request. Such as:</p>
  
  <ol>
  <li>User makes request (as before).</li>
  <li>Message "Retrieving ABC" displayed</li>
  <li>Message "Retrieving XYZ" displayed</li>
  <li>Message "Processing data" displayed</li>
  <li>Full response as normal.</li>
  </ol>
  
  <p><strong>How can I go about doing this?</strong> I don't think that sending back multiple JavaScript responses to one request is possible, but have no idea what the correct way of doing this is!</p>