title: How to do asynchronous processing in nodejs
body: <p>I'm a newbie in node js and trying to build a simple app to build web pages from RSS feeds.</p>
  
  <pre><code>http.get('http://www.someurl.com/news?output=rss', function(res) {
      res.on('data', function(chunk) {
          resLength += chunk.length; 
          chunks.push(chunk);
      });
      res.on('end', function(chunk) {
          // combine all chunks and process feed XML.
      });
  })
  </code></pre>
  
  <p>Processing the server response may go longer and will block the main thread.</p>
  
  <p>How can I create an async operation to process the intermediate server response and send the result back?</p>