self.addEventListener('activate', function(e) {
    console.log('[ServiceWorker] Activate');
    e.waitUntil(
        caches.keys().then(function(keyList) {
            return Promise.all(keyList.map(function(key) {
                if (key !== cacheFileName && key != cacheCdnName) {
                    console.log('[ServiceWorker] Removing old cache', key);
                    return caches.delete(key);
                }
            }));
        })
    );
});