Service worker registers on every sub-URL - service-worker

Question

I have a site with a service worker and it registers every time a new sub-URL is visited. Is this the expected behaviour?
Example. My root URL is mysite.com. The SW registers OK when I visit that URL. When I visit mysite.com/subpage, it registers as a new service worker for that URL too.
Please tell me if I am doing something wrong or if this is the way the SWs work.
My service worker recache the resources everytime it installs, so I'm guessing it is recaching everything everytime the user visits a sub-URL for the first time. Isn't that not recommended?
This is my SW.
var staticCacheName = "bspev-v" + new Date().getTime();
var filesToCache = [
'/',
'/offline',
'/css/app.css',
'/js/app.js',
'/js/rutas.js',
// iconos app
'/images/icons/icon-72x72.png',
'/images/icons/icon-96x96.png',
'/images/icons/icon-128x128.png',
'/images/icons/icon-144x144.png',
'/images/icons/icon-152x152.png',
'/images/icons/icon-192x192.png',
'/images/icons/icon-384x384.png',
'/images/icons/icon-512x512.png',
'/favicon.ico',
// imagenes app
'/images/logotexto.png',
'/images/offline.png',
// ajax
'/api/prestamos/pendientes',
//fuentes app
'https://fonts.googleapis.com/css?family=Archivo+Narrow&display=swap',
'https://fonts.gstatic.com/s/archivonarrow/v11/tss0ApVBdCYD5Q7hcxTE1ArZ0bbwiXw.woff2',
// vue
'/js/vue.js',
'/js/vue.min.js',
// fontawesome
'/css/fa-all.css',
'/webfonts/fa-solid-900.woff2'
];
// Cache on install
self.addEventListener("install", event => {
this.skipWaiting();
event.waitUntil(
caches.open(staticCacheName)
.then(cache => {
console.log('Service Worker instalado.');
return cache.addAll(filesToCache);
})
)
});
// Clear cache on activate
self.addEventListener('activate', event => {
event.waitUntil(
caches.keys().then(cacheNames => {
return Promise.all(
cacheNames
.filter(cacheName => (cacheName.startsWith("bspev-")))
.filter(cacheName => (cacheName !== staticCacheName))
.map(cacheName => caches.delete(cacheName))
);
})
);
});
// Serve from Cache
self.addEventListener("fetch", event => {
const requestURL = new URL(event.request.url);
//Handle api calls
if (/\/api\//.test(requestURL.pathname)) {
event.respondWith(
fetch(event.request).then(response => {
event.waitUntil(
caches.open(staticCacheName).then(cache => {
cache.put(event.request, response.clone());
})
);
return response.clone();
}).catch(function() {
return caches.match(event.request);
})
);
} else {
event.respondWith(
caches.match(event.request)
.then(response => {
return response || fetch(event.request);
})
.catch(() => {
return caches.match('offline');
})
);
}
});
This is the SW registration
<script type="text/javascript">
// Initialize the service worker
if ('serviceWorker' in navigator) {
navigator.serviceWorker.register('/serviceworker.js', {
scope: '.'
}).then(function (registration) {
// Registration was successful
console.log('Laravel PWA: ServiceWorker registration successful with scope: ', registration.scope);
}, function (err) {
// registration failed :(
console.log('Laravel PWA: ServiceWorker registration failed: ', err);
});
} else { console.log('no serviceWorker in navigator') }
</script>