title: How to protect routes in express.js?
body: <p>For example, in Meteor, there's something like </p>
  
  <pre><code>Router.plugin('ensureSignedIn');
  Router.plugin('ensureSignedIn', {
    except: ['home', 'atSignIn', 'atSignUp', 'atForgotPassword']
  });
  </code></pre>
  
  <p>So unsigned user cannot access other routes except above four.</p>
  
  <p>How to do this in express.js? I'm using passport.js also.</p>