Add service workers scripts

cacher.js

@@ -0,0 +1,40 @@
+const CACHE_NAME = 'blog'
+const URLS_TO_CACHE = [
+  '/',
+  '/index.html',
+  '/assets/css/main.css',
+  '/assets/js/script.js',
+  '/assets/header-background.jpeg',
+  '/assets/favicon-96x96.png'
+]
+
+this.addEventListener('install', event => {
+  event.waitUntil(
+    caches.open(CACHE_NAME).then(cache => {
+      return cache.addAll(URLS_TO_CACHE)
+    })
+  )
+})
+
+this.addEventListener('fetch', event => {
+  let request = event.request
+  let url = new URL(event.request.url)
+
+  if (url.origin !== location.origin)
+    return
+
+  event.respondWith(
+    caches.open(CACHE_NAME).then(cache => {
+      return cache.match(request).then(result => {
+        if (result) {
+          return result
+        } else {
+          return fetch(request).then(response => {
+            cache.put(request, response.clone())
+            return response
+          })
+        }
+      })
+    })
+  )
+})

service-workers.js

@@ -0,0 +1,9 @@
+if ('serviceWorker' in navigator) {
+  navigator.serviceWorker.register('/cacher.js', {scope: '/'})
+    .then(response => {
+      console.log('Worker installed successfully. Scope: ', response.scope)
+    })
+    .catch(error => {
+      console.log("There's an error in the worker installation: ", error)
+    })
+}