Delete all caches from within service-worker

service-worker.js

self.addEventListener('activate', event => {
  event.waitUntil(
    caches.keys().then(allCaches => {
      return Promise.all(allCaches.map(cacheToDelete => {
        return caches.delete(cacheToDelete);
      }));
    }).then(() => self.clients.claim())
  );
});