title: how to set maximum size limit for incoming socket.io message
body: <p>we want our server to block any messages that contain data larger than 7 kb.</p>
  
  <p>our serverside code:</p>
  
  <pre><code>socket.on('startdata', function (data) {
  
          console.log(data.text);});
  </code></pre>
  
  <p>our clientside code:</p>
  
  <pre><code>        socket.emit('startdata', { text: 'testtext blah blah' });
  </code></pre>
  
  <p>is there a way to check  the data size and refuse to accept the message before the data gets passed to the <code>socket.on</code> function ?</p>