sw.js

var APP_PREFIX = 'ClearMyRecordTulsa_';     // Identifier for this app (this needs to be consistent across every cache update)
var VERSION = 'version_01';              // Version of the off-line cache (change this value everytime you want to update cache)
var CACHE_NAME = APP_PREFIX + VERSION;
var URLS = [                            // Add URL you want to cache in this list.
          '/clear-my-record/',                     // If you have separate JS/CSS files,
          '/clear-my-record/index.html'            // add path to those files here
];
// Respond with cached resources
self.addEventListener('fetch', function (e) {
    console.log('fetch request : ' + e.request.url);
  e.respondWith(
    caches.match(e.request).then(function (request) {
      if (request) { // if cache is available, respond with cache
          console.log('responding with cache : ' + e.request.url);
          return request;
      } else {       // if there are no cache, try fetching request
          console.log('file is not cached, fetching : ' + e.request.url);
          return fetch(e.request);
      }

    })
  );
});
// Cache resources
self.addEventListener('install', function (e) {
  e.waitUntil(
    caches.open(CACHE_NAME).then(function (cache) {
        console.log('installing cache : ' + CACHE_NAME);
        return cache.addAll(URLS);
    })
  );
});
// Delete outdated caches
self.addEventListener('activate', function (e) {
  e.waitUntil(
    caches.keys().then(function (keyList) {
    // `keyList` contains all cache names under your username.github.io
    // filter out ones that has this app prefix to create white list
    var cacheWhitelist = keyList.filter(function (key) {
        return key.indexOf(APP_PREFIX);
    });
    // add current cache name to white list
        cacheWhitelist.push(CACHE_NAME);
    return Promise.all(keyList.map(function (key, i) {
      if (cacheWhitelist.indexOf(key) === -1) {
          console.log('deleting cache : ' + keyList[i] );
          return caches.delete(keyList[i]);
      }
    }));
    })
  );
});