Example of staleWhileRevalidate + broadcastCacheUpdate

app.js

const HN_URL = 'https://hackernewsapi.example.com/';

function updateUI(hnData) {
  // Update the DOM.
}

async function init() {
  const channel = new BroadcastChannel('hn-updates');
  channel.addEventListener('message', async (event) => {
    if (event.data.payload.updatedUrl === HN_URL) {
      const response = await caches.match(HN_URL);
      const hnData = await response.json();
      updateUI(hnData);
    }
  });

  const response = await fetch(HN_URL);
  const hnData = await response.json();
  updateUI(hnData);
}

sw.js

// Other workboxSW usage...

workboxSW.registerRoute(
  new RegExp('^https://hackernewsapi.example.com/'),
  workboxSW.strategies.staleWhileRevalidate({
    broadcastCacheUpdate: {
      channelName: 'hn-updates',
    },
  })
);