Pfthb

Fairly new to Service workers and JS promises so any help is appreciated.

The webpage that's failing:

https://icbmaeronautics.co.uk

The Error as shown in Chrome Dev Tools:

The FetchEvent for "http://localhost:3005/" resulted in a network error 
response: the promise was rejected.
Promise.catch (async)
(anonymous) @ sw.js:29
sw.js:1 Uncaught (in promise) TypeError: Failed to fetch

The markup for registering service worker (Seems to work fine)

if('serviceWorker' in navigator) 
 navigator.serviceWorker
 .register('/sw.js')
 .then(function() console.log("Service Worker Registered"); );
 

The install code within the sw.js script file

self.addEventListener('install', function(e) 
 e.waitUntil(
 caches.open('airhorner').then(function(cache) 
 /* Particular urls which all install with code 200s */
 )
 );
);

And finally the fetch code which seems to have an issue with the event.respondWith() function

self.addEventListener('fetch', event => 
// Let the browser do its default thing
// for non-GET requests.
if (event.request.method != 'GET') return;

// Prevent the default, and handle the request ourselves.
event.respondWith(async function() 
// Try to get the response from a cache.
const cache = await caches.open('dynamic-v1');
const cachedResponse = await cache.match(event.request);

if (cachedResponse) 
 // If we found a match in the cache, return it, but also
 // update the entry in the cache in the background.
 event.waitUntil(cache.add(event.request));
 return cachedResponse;


// If we didn't find a match in the cache, use the network.
return fetch(event.request);
());
);