Check if a new version of the website is available and show a notification to the user for reloading the page in order to see the new website

sw-new-version-notification.js

if ('serviceWorker' in navigator) { 
  navigator.serviceWorker.register('/service-worker.js', {scope: '/'})
  .then(function(registration) {
      registration.onupdatefound = () => {
          const newServiceWorker = registration.installing;
          newServiceWorker.onstatechange = () => {
              switch (newServiceWorker.state) {
                  case 'installing': 
                      if (navigator.serviceWorker.controller) {
                          document.getElementById('new-version-banner').innerHTML('A new version of the website is available 🙋. <a onclick="window.location.reload()">Reload</a> to see all the new goodness 💠');
                      }
              }
          }
      }
      console.log('Service Worker registration succeeded. Scope is ' + registration.scope);
      
  }).catch(function(error) {
      console.log('Service Worker registration failed with ' + error);
  });
}