How to integrate the prototype kit with GOV.UK Notify

routes.js

// Add this code to the top of routes.js
// process.env.NOTIFYAPIKEY is a special kind of variable that Node
// pulls from the environment your prototype is running in
//
// To set it locally, run this command in your Terminal, in the root
// folder of your prototype:
//     echo NOTIFYAPIKEY=xxxxxxx >> .env
// (where xxxxxxx is a key you’ve created in Notify)
//
// To set it on Heroku, go to the settings page on your app, click
// ‘reveal config vars’ and enter NOTIFYAPIKEY and the value of the key
// in the two boxes.

var NotifyClient = require('notifications-node-client').NotifyClient,
    notify = new NotifyClient(process.env.NOTIFYAPIKEY),


// ---------------------------------------------------------------------
// Add these bits at the bottom of routes.js

// The URL here should be the same as the form where someone enters
// their email address/phone number
//
// That page needs a textbox called 'email', to match req.body.email
// below, eg <input type='text' name='email' />
//
router.post('/page-with-contact-details-form', function (req, res) {

  notify.sendEmail(
    // this long string is the template ID, get it from Notify
    '24a8b897-2de9-4a9f-a2db-b6ef682f799a',
    req.body.email,
    {}
  );

  // This URL should be the page you want to send people to after the 
  // email message has been sent
  res.redirect('/journey/dvla-change-address/' + req.params.id + '/confirm-email');

});