title: Update Express.js's local route variables without reloading the page
body: <p>I'm using node.js with the express.js framework and EJS to handle the templates.</p>
  
  <p>Here's my route:</p>
  
  <pre><code>app.get('/',function(req,res) {
    res.render('index', {
      matches: [],
      status_message: '',
      message: ''
    });
  });
  </code></pre>
  
  <p>When I call app.post, I run queries to a database updating variables <code>'matches'</code> and <code>'status_message'</code>.  How would I update these variables rendered in the page without having the page reload.</p>
  
  <p>For example, if the user provides invalid credentials, I'd like update the <code>'status_message'</code> to "Invalid Credentials".</p>