1 files changed, 52 insertions, 0 deletions
diff --git a/serviceWorker.js b/serviceWorker.js
new file mode 100644
index 0000000..ba9ca7a
--- /dev/null
+++ b/serviceWorker.js
@@ -0,0 +1,52 @@
+const CACHE_NAME = 'offline-cache-v1'
+const ASSETS = [
+    '/',
+    '/index.html',
+    '/styles.css',
+    '/styles3.css',
+    '/tempo.md',
+    '/bell.png',
+    '/bell.svg',
+    '/by-sa.png',
+    '/cc-by-sa-legalcode.txt',
+    '/symbols.txt'
+]
+
+self.addEventListener('install', e => {
+    console.log('installing sw')
+    e.waitUntil(caches.open(CACHE_NAME).then(cache => cache.addAll(ASSETS)))
+    self.skipWaiting()
+})
+
+self.addEventListener('activate', e => {
+    console.log('sw activated')
+    e.waitUntil(self.clients.claim())
+})
+
+self.addEventListener('fetch', e => {
+    const url = new URL(e.request.url)
+    const isTarget = ASSETS.includes(url.pathname) || url.pathname.startsWith('/fonts/')
+
+    if (!isTarget) return
+
+    e.respondWith(
+        caches.open(CACHE_NAME).then(async cache => {
+            const cachedResponse = await cache.match(e.request)
+
+            if (cachedResponse) console.log(`cache ${url.pathname}`)
+            else console.log(`fetch ${url.pathname}`)
+
+            const networkFetch = fetch(e.request).then(networkResponse => {
+                if (networkResponse.ok) {
+                    console.log(`updating ${url.pathname}`)
+                    cache.put(e.request, networkResponse.clone())
+                }
+                return networkResponse
+            }).catch(err => {
+                console.error(`failed ${url.pathname}:`, err)
+            })
+
+            return cachedResponse || networkFetch
+        })
+    )
+})
+\ No newline at end of file