Caches everything

service-worker-browser.js

/*
 * main.js
 * Copyright (C) 2016 romgrk <romgrk@Romgrk-ARCH>
 *
 * Distributed under terms of the MIT license.
 */
'use strict';

const serviceWorker = navigator.serviceWorker;

serviceWorker.register('/sw.js')
.then(registration => {
  console.log('SW done:', registration)
})
.catch(err => {
  console.log('SW failed:', err)
})


document.addEventListener('DOMContentLoaded', event => {
  sendToServiceWorker('Page loaded')
  .then(res => console.log(res))
  .catch(err => console.log(err))
})

function sendToServiceWorker(message) {
  return new Promise((resolve, reject) => {
    var channel = new MessageChannel();
    channel.port1.onmessage = event => {
      if (event.data.error)
        reject(event.data.error)
      else
        resolve(event.data)
    }
    serviceWorker.controller.postMessage(message, [channel.port2])
  })
}

service-worker.js

/*
 * sw.js
 * Copyright (C) 2016 romgrk <romgrk@Romgrk-ARCH>
 *
 * Distributed under terms of the MIT license.
 */
'use strict';

const CACHE_NAME = 'cache-v1'
const urls = [
  'file.txt'
]

let counter = 0

self.addEventListener('install', (event) => {
  console.log('SW: installing');
  event.waitUntil(
    caches.open(CACHE_NAME).then((cache) => {
      console.log('Cache opened');
      return cache.addAll(urls)
    })
  )
})

self.addEventListener('activate', (event) => {
  console.log('SW: activating');
})

self.addEventListener('fetch', event => {
  console.log('SW: fetch:', event);
  event.respondWith(
    caches.match(event.request).then(cachedResponse => {
      if (cachedResponse) {
        console.log('Cache match.');
        const fetchRequest = event.request.clone();
        fetch(fetchRequest).then(response => {
          if (!response || response.status !== 200 || response.type !== 'basic') {
            return;
          }
          console.log('Cache match -- recache');
          caches.open(CACHE_NAME).then(cache => {
            cache.put(event.request, response);
          });
        })

        return cachedResponse;
      }

      console.log('Cache miss');

      const fetchRequest = event.request.clone();
      return fetch(fetchRequest).then(response => {
        if (!response || response.status !== 200 || response.type !== 'basic') {
          return response;
        }

        console.log('Cached');
        const responseToCache = response.clone();

        caches.open(CACHE_NAME).then(cache => {
          cache.put(event.request, responseToCache);
        });

        return response;
      })
    })
  )
})

self.addEventListener('message', event => {
  console.log('SW: message:', event.data);

  if (event.ports.length) {
    var port = event.ports[0];
    port.postMessage('Received.');
  }
})


function sendToAllClients(message) {
  clients.matchAll().then(clients => {
    clients.forEach(client => sendToClient(client, message))
  })
}

function sendToClient(client, message) {
  return new Promise((resolve, reject) => {
    var channel = new MessageChannel();

    channel.port1.onmessage = event => {
      if (event.data.error)
        reject(event.data.error)
      else
        resolve(event.data)
    }

    client.postMessage(message, [channel.port2])
  })
}