Requests are not intercepted when cached by Service Worker

Not sure if this is by design but requests that were previously cached by service worker are not intercepted after page.setRequestInterception(true).

Simplified code to reproduce:

const hostname = 'http://localhost:';
const {port, proc} = await startServer(); // local implementation
const browser = await puppeteer.launch({
  args: [
    '--no-sandbox',
    '--disable-setuid-sandbox',
    '--enable-features=NetworkService',
  ],
  ignoreHTTPSErrors: true,
});

const page = await browser.newPage();

await page.goto(`${hostname}${port}`);
await page.evaluate('navigator.serviceWorker.ready');

await page.setRequestInterception(true); //toggle this
page.on('request', req => {
   console.log('requesting', req.url());
   req.continue().catch(e => e /* not intercepting */);
});

await page.reload({waitUntil: 'domcontentloaded'});

await browser.close();

1. Set await page.setRequestInterception(true)
2. Run test, only URLs not previously cached by service worker are logged
3. Set await page.setRequestInterception(false) (or remove Service Worker registration)
4. Run test, all URLs are logged

Are requests intercepted only when requests are sent through to the network, or is this a bug?

[aslushnikov]

@angus-c we decided not to land #4095.

Summary: yes, requests are not intercepted when they come to service worker. Ideally, we want:

• connect to page’s service worker
• expose ServiceWorker network API similar to the page’s one: serviceWorker.on('request'), serviceWorker.on('response'), serviceWorker.setRequestInterception(true).
• page’s network events should relate to all network requests initiated by page
• serviceWorker network events should relate to all network requests initiated by SW

While we don’t have this implemented, Puppeteer simply doesn’t fire any request events if they are captured by SW and request interception is enabled. If this is a no-go, one can use DevTools protocol to enable SW by-passing for network:

page._client.send('Network.setBypassServiceWorker', {bypass: true})

[JulianSoto]

What’s the purpose of have a HTTPResponse.fromServiceWorker() method if it won’t work when request interception is set true?