serviceWorker.js

importScripts('app/lib/workbox-sw.js');

let constants = {};
constants.SW_EVENT_ACTIVATED = 'SW_EVENT_ACTIVATED';
constants.SW_EVENT_URL_CACHED = 'SW_EVENT_URL_CACHED';
constants.SW_EVENT_REQ_CACHE = 'SW_EVENT_REQ_CACHE';
constants.SW_CACHE_TYPE_IMG = 'CACHE_TYPE_IMG';
constants.SW_CACHE_TYPE_GENERIC = 'CACHE_TYPE_GENERIC';

if (!workbox) {
    console.log("Workbox in service worker failed to load!");
}
self.__WB_DISABLE_DEV_LOGS = true;
/*workbox.setConfig({
    debug: true
});*/

self.addEventListener('install', (event) => {
    console.log('installing service worker ...');
    let urls = ["/","/latest/","index.html","app/build/288.bundle.js","app/build/392.bundle.js","app/build/733.bundle.js","app/build/856.bundle.js","app/build/950.bundle.js","app/build/asterics-grid.bundle.js","app/build/hls.js.bundle.js","app/build/html2canvas.bundle.js","app/build/jspdf.bundle.js","app/css/bootstrap-grid.css","app/css/custom.css","app/css/fontawesome/css/all.css","app/css/fontawesome/webfonts/fa-brands-400.eot","app/css/fontawesome/webfonts/fa-brands-400.svg","app/css/fontawesome/webfonts/fa-brands-400.ttf","app/css/fontawesome/webfonts/fa-brands-400.woff","app/css/fontawesome/webfonts/fa-brands-400.woff2","app/css/fontawesome/webfonts/fa-regular-400.eot","app/css/fontawesome/webfonts/fa-regular-400.svg","app/css/fontawesome/webfonts/fa-regular-400.ttf","app/css/fontawesome/webfonts/fa-regular-400.woff","app/css/fontawesome/webfonts/fa-regular-400.woff2","app/css/fontawesome/webfonts/fa-solid-900.eot","app/css/fontawesome/webfonts/fa-solid-900.svg","app/css/fontawesome/webfonts/fa-solid-900.ttf","app/css/fontawesome/webfonts/fa-solid-900.woff","app/css/fontawesome/webfonts/fa-solid-900.woff2","app/css/images/ui-icons_444444_256x240.png","app/css/images/ui-icons_555555_256x240.png","app/css/images/ui-icons_777620_256x240.png","app/css/images/ui-icons_777777_256x240.png","app/css/images/ui-icons_cc0000_256x240.png","app/css/images/ui-icons_ffffff_256x240.png","app/css/jquery-ui.css","app/css/skeleton.css","app/fonts/Arimo-Regular-Cyrillic.ttf","app/img/DonationButtons.svg","app/img/app-icons/Icon-144.png","app/img/app-icons/Icon-192.png","app/img/app-icons/Icon-36.png","app/img/app-icons/Icon-48.png","app/img/app-icons/Icon-512.png","app/img/app-icons/Icon-72.png","app/img/app-icons/Icon-96.png","app/img/arasaac.png","app/img/asterics-grid-icon-inkscape.svg","app/img/asterics-grid-icon-raw.svg","app/img/asterics-grid-icon.png","app/img/asterics-grid-iconHQ.png","app/img/asterics_icon.png","app/img/betterplace-donation-button.png","app/img/donate-open-collective.png","app/img/donate-paypal.png","app/img/favicon.ico","app/img/fhtw.svg","app/img/logo_with_border.png","app/img/ma23_logo_neu.jpg","app/img/responsive-voice-license.png","app/index.html","app/lib/dom-i18n.min.js","app/lib/gridList.js","app/lib/jquery-ui.min.js","app/lib/jquery.contextMenu.min.js","app/lib/jquery.gridList.js","app/lib/jquery.min.js","app/lib/jquery.ui.position.min.js","app/lib/jquery.ui.touchpunch.min.js","app/lib/loglevel.min.js","app/lib/modernizr-custom.js","app/lib/object-model.min.js","app/lib/pouchdb-8.0.1.min.js","app/lib/puck.js","app/lib/responsive-voice.js","app/lib/sjcl.min.js","app/lib/uart.min.js","app/lib/workbox-sw.js","app/manifest.appcache","app/manifest.webmanifest","app/privacy_de.html","app/privacy_en.html"];
    const cacheName = workbox.core.cacheNames.runtime;
    let promise = caches.delete(cacheName).then(() => {
        return caches.open(cacheName);
    }).then((cache) => {
        return Promise.all(
            urls.map(function (url) {
                return cache.add(url).catch(function (reason) {
                    console.warn(`failed to fetch "${url}" in Service Worker.`);
                    console.warn(reason);
                    return Promise.resolve();
                });
            })
        );
    });
    event.waitUntil(promise);
    self.skipWaiting();
});

self.addEventListener('activate', event => {
    clients.claim();
    sendToClients({type: constants.SW_EVENT_ACTIVATED, activated: true});
    console.log('Service Worker active! Version: https://github.com/asterics/AsTeRICS-Grid/releases/tag/#ASTERICS_GRID_VERSION#');
});

self.addEventListener('message', (event) => {
    let msg = event.data;
    if(!msg || msg.type !== constants.SW_EVENT_REQ_CACHE || !msg.url) {
        return;
    }
    let cacheName = msg.cacheType === constants.SW_CACHE_TYPE_IMG ? 'image-cache' : workbox.core.cacheNames.runtime;

    caches.open(cacheName).then(async (cache) => {
        let responseCode = await getResponseCode(cache, msg.url);
        if (responseCode !== 200) {
            //console.debug(`adding ${msg.url} to cache "${cacheName}".`);
            let response = await fetch(msg.url);
            responseCode = response.status;
            if (responseCode === 200) {
                await cache.put(msg.url, response);
            }
        }
        sendToClients({type: constants.SW_EVENT_URL_CACHED, url: msg.url, success: responseCode === 200, responseCode: responseCode});
    });
});

workbox.routing.registerRoute(({url, request, event}) => {
    //console.debug(`${url.href} should cache normal: ${shouldCacheNormal(url, request)}`);
    return shouldCacheNormal(url, request);
}, new workbox.strategies.CacheFirst());

workbox.routing.registerRoute(({url, request, event}) => {
    //console.debug(`${url.href} should cache image: ${shouldCacheImage(url, request)}`);
    return shouldCacheImage(url, request);
}, new workbox.strategies.CacheFirst({
    cacheName: 'image-cache',
    fetchOptions: {
        mode: 'cors',
        credentials: 'omit'
    }
}));

function shouldCacheImage(url, request) {
    let isOwnHost = url.hostname === 'grid.asterics.eu';
    let isImageRequest = request.destination === 'image';
    return !isOwnHost && isImageRequest;
}

function shouldCacheNormal(url, request) {
    let isOwnHost = url.hostname === 'grid.asterics.eu';
    return !shouldCacheImage(url, request) && isOwnHost;
}

async function getResponseCode(cache, url) {
    let response = await cache.match(url);
    return response ? response.status : -1;
}

function sendToClients(msg) {
    self.clients.matchAll().then(clients => {
        clients.forEach(client => client.postMessage(msg));
    });
}