remove old cache when service worker is updated

cache-sw-delete.js

const prefix = 'version-dependent';
const version = 1.0.0;
self.addEventListener('activate', function (event) {
  event.waitUntil(
    caches.keys().then(function (cacheNames) {
      return Promise.all(
        cacheNames.filter(function (cacheName) {
          if(cacheName.startsWith(prefix)){
            if(cacheName.endsWith(version){
               return false;
             }
               return true;
          }
               return false;
        }).map(function (cacheName) {
          return caches.delete(cacheName);
        })
      );
    })
  );
});