title: How to render 2 pages for 1 req (express js)
body: <p>I have a simple application, which asks client for incoming data, makes calculations and provides an answer. Calculations performed several seconds by the server, so, all this time client see the data input form and tries to push "send" button several times. Obviously, server handles all these requests. The better way to fix this - is using some "wait" page. But I can't find the way how to render "wait" page first and the final page after calculations.</p>
  
  <p>Unfortunately I cannot use the javascripts at the client side.</p>
  
  
  
  <pre class="lang-js prettyprint-override"><code>app.post('/answer', function (req, res, next) 
  {       
    res.render('pleaseWait.jade');
    someLongFunction();
    next(req, res);
  }, function(req, res)
  {
    res.render('targetPage.jade');
  });
  </code></pre>
  
  <p>
  Such code doesn't work. </p>
  
  <p>Any ideas how to organize the rendering of both pages one-by-one?</p>