PWA Day06 - cache then network

sw.js

// Here is the code in the sw.js:
self.addEventListener('fetch', function(event) {
  event.respondWith(
    caches
      .open('mysite-dynamic')
      .then(function(cache) {
        return fetch(event.request)
          .then(function(response) {
            cache.put(event.request, response.clone())

            return response
          })
      })
  )
})