show-notification.js

self.addEventListener('push', (event) => {
  const title = 'New notification';
  const body = 'We have received a push notification.';
  const icon = '/app-icon-192.png';
  const tag = 'push-notification-tag';
  
  event.waitUntil(
    self.registration.showNotification(title, {
      body,
      icon,
      tag
    })
  );
});