devplacepy/devplacepy/static/service-worker.js

// retoor <retoor@molodetz.nl>

const CACHE_NAME = "devplace-shell-v1";
const OFFLINE_URL = "/static/offline.html";
const PRECACHE_URLS = [
    OFFLINE_URL,
    "/manifest.json",
    "/static/icon-192.png",
    "/static/icon-512.png",
];
const DEFAULT_URL = "/notifications";
const DEFAULT_ICON = "/static/icon-192.png";

self.addEventListener("install", (event) => {
    event.waitUntil(
        caches.open(CACHE_NAME).then((cache) => cache.addAll(PRECACHE_URLS)).then(() => self.skipWaiting())
    );
});

self.addEventListener("activate", (event) => {
    event.waitUntil(
        caches.keys()
            .then((names) => Promise.all(names.filter((name) => name !== CACHE_NAME).map((name) => caches.delete(name))))
            .then(() => self.clients.claim())
    );
});

self.addEventListener("fetch", (event) => {
    if (event.request.mode !== "navigate") {
        return;
    }
    event.respondWith(
        fetch(event.request).catch(() => caches.match(OFFLINE_URL))
    );
});

function isClientOpen(url) {
    return clients.matchAll().then((matchedClients) =>
        matchedClients.some((client) => client.url === url && "focus" in client)
    );
}

self.addEventListener("push", (event) => {
    event.waitUntil(handlePush(event));
});

async function handlePush(event) {
    if (!self.Notification || self.Notification.permission !== "granted") {
        return;
    }

    const data = event.data ? event.data.json() : {};
    const url = data.url || DEFAULT_URL;

    if (await isClientOpen(url)) {
        return;
    }

    const title = data.title || "DevPlace";
    const message = data.message || "You have a new notification.";
    const icon = data.icon || DEFAULT_ICON;

    await self.registration.showNotification(title, {
        body: message,
        icon: icon,
        badge: icon,
        tag: "devplace-notification",
        data: data,
    });
}

self.addEventListener("notificationclick", (event) => {
    event.notification.close();
    const url = event.notification.data && event.notification.data.url ? event.notification.data.url : DEFAULT_URL;
    event.waitUntil(clients.openWindow(url));
});