ServiceWorker cache polyfill

This is a polyfill for the ServiceWorker cache API.

Usage

Take serviceworker-cache-polyfill.js, then in your ServiceWorker script:

importScripts('serviceworker-cache-polyfill.js');

// example usage:
self.addEventListener('install', function(event) {
  event.waitUntil(
    caches.open('demo-cache').then(function(cache) {
      return cache.put('/', new Response("From the cache!"));
    })
  );
});

self.addEventListener('fetch', function(event) {
  event.respondWith(
    caches.match(event.request).then(function(response) {
      return response || new Response("Nothing in the cache for this request");
    })
  );
});