self.addEventListener('install', function() {
  self.skipWaiting();
});

self.addEventListener('activate', function(event) {
  event.waitUntil(
    caches
      .keys()
      .then(function(cacheNames) {
        return Promise.all(
          cacheNames.map(function(cacheName) {
            return caches.delete(cacheName);
          })
        );
      })
      .then(function() {
        return self.registration.unregister();
      })
      .then(function() {
        return self.clients.matchAll();
      })
      .then(function(clients) {
        clients.forEach(function(client) {
          client.navigate(client.url);
        });
      })
  );
});