Service worker issue: page never loads when page is refreshed with "update on reload" checked

9
votes

Demo video: https://www.youtube.com/watch?v=UBfnvx6jC_A

I followed along with Udacity's Offline Web Applications course in order to get my app working offline. Here is my code:

main.js

// other stuff above
if (navigator.serviceWorker) {
  navigator.serviceWorker.register('/service-worker.js').catch(function() {
    console.log('Service worker registration failed.');
  });
}

service-worker.js

let currCacheName = 'premium-poker-tools-1';

self.addEventListener('install', function(event) {
  event.waitUntil(
    caches.open(currCacheName).then(function(cache) {
      let promise = cache.addAll([
        '/',
        'app.js',
        // 'c7d016677eb7e912bc40.worker.js',
        // 'f328c7e2b379df12fa4c.worker.js',
        'static/logo.png',
        'static/favicon.png',
        'static/loading.svg',
        'static/cards/ace-of-clubs.png',
        'static/cards/king-of-clubs.png',
        'static/cards/queen-of-clubs.png',
        'static/cards/jack-of-clubs.png',
        'static/cards/ten-of-clubs.png',
        'static/cards/nine-of-clubs.png',
        'static/cards/eight-of-clubs.png',
        'static/cards/seven-of-clubs.png',
        'static/cards/six-of-clubs.png',
        'static/cards/five-of-clubs.png',
        'static/cards/four-of-clubs.png',
        'static/cards/three-of-clubs.png',
        'static/cards/two-of-clubs.png',
        'static/cards/ace-of-spades.png',
        'static/cards/king-of-spades.png',
        'static/cards/queen-of-spades.png',
        'static/cards/jack-of-spades.png',
        'static/cards/ten-of-spades.png',
        'static/cards/nine-of-spades.png',
        'static/cards/eight-of-spades.png',
        'static/cards/seven-of-spades.png',
        'static/cards/six-of-spades.png',
        'static/cards/five-of-spades.png',
        'static/cards/four-of-spades.png',
        'static/cards/three-of-spades.png',
        'static/cards/two-of-spades.png',
        'static/cards/ace-of-hearts.png',
        'static/cards/king-of-hearts.png',
        'static/cards/queen-of-hearts.png',
        'static/cards/jack-of-hearts.png',
        'static/cards/ten-of-hearts.png',
        'static/cards/nine-of-hearts.png',
        'static/cards/eight-of-hearts.png',
        'static/cards/seven-of-hearts.png',
        'static/cards/six-of-hearts.png',
        'static/cards/five-of-hearts.png',
        'static/cards/four-of-hearts.png',
        'static/cards/three-of-hearts.png',
        'static/cards/two-of-hearts.png',
        'static/cards/ace-of-diamonds.png',
        'static/cards/king-of-diamonds.png',
        'static/cards/queen-of-diamonds.png',
        'static/cards/jack-of-diamonds.png',
        'static/cards/ten-of-diamonds.png',
        'static/cards/nine-of-diamonds.png',
        'static/cards/eight-of-diamonds.png',
        'static/cards/seven-of-diamonds.png',
        'static/cards/six-of-diamonds.png',
        'static/cards/five-of-diamonds.png',
        'static/cards/four-of-diamonds.png',
        'static/cards/three-of-diamonds.png',
        'static/cards/two-of-diamonds.png',
        'static/feedback/1.png',
        'static/feedback/2.png',
        'static/feedback/3.png',
        'static/feedback/4.png',
        'static/feedback/flop-selector.png',
        'static/feedback/green-grid-squares.png',
        'static/feedback/user-set-range-to-simulate-to-street.png',
        'static/guides/beginners-guide/1.png',
        'static/guides/beginners-guide/2.png',
        'static/guides/beginners-guide/3.png',
        'static/guides/beginners-guide/4.png',
        'static/guides/beginners-guide/5.png',
        'static/guides/beginners-guide/6.png',
        'static/guides/beginners-guide/7.png',
        'static/guides/beginners-guide/8.png',
        'static/guides/beginners-guide/9.png',
        'static/guides/beginners-guide/10.png',
        'static/guides/beginners-guide/11.png',
        'static/guides/beginners-guide/12.png',
        'static/guides/beginners-guide/13.png',
        'static/guides/beginners-guide/14.png',
        'static/guides/beginners-guide/15.png',
        'static/guides/beginners-guide/16.png',
        'static/guides/beginners-guide/17.png',
        'static/guides/beginners-guide/18.png',
        'static/guides/beginners-guide/19.png',
        'static/guides/beginners-guide/20.png',
        'static/guides/beginners-guide/21.png',
        'static/guides/faq/double-counting/1.png',
        'static/guides/faq/hit-percentage-calculation/1.png',
        'static/guides/faq/hit-percentage-calculation/2.png',
        'static/guides/faq/hit-percentage-calculation/3.png',
        'static/guides/faq/insights/1.png',
        'static/guides/faq/insights/2.png',
        'static/guides/faq/insights/3.png',
        'static/guides/faq/insights/4.png',
        'static/guides/faq/insights/5.png',
        'static/guides/faq/insights/6.png',
        'static/guides/faq/insights/7.png',
        'static/guides/faq/insights/8.png',
        'static/guides/faq/set-checks-to-default/1.png',
        'static/guides/quick-guide/1.png',
        'static/guides/quick-guide/2.png',
        'static/guides/quick-guide/3.png',
        'static/guides/quick-guide/4.png',
        'static/guides/quick-guide/5.png',
        'static/guides/quick-guide/6.png',
        'static/guides/quick-guide/7.png',
        'static/guides/quick-guide/8.png',
        'static/guides/quick-guide/save-load-scenario.png',
        'static/home/1.png',
        'static/home/2.png',
        'static/home/3.png',
        'static/settings/equity-calculator-insights-not-visible.png',
        'static/settings/equity-calculator-insights-visible.png',
        'static/settings/outcome-analyzer-checkboxes-collapsed-1.png',
        'static/settings/outcome-analyzer-checkboxes-collapsed-2.png',
        'static/settings/outcome-analyzer-checkboxes-included-1.png',
        'static/settings/outcome-analyzer-checkboxes-included-2.png',
        'static/settings/outcome-analyzer-hands.png',
        'static/settings/outcome-analyzer-insights-not-visible.png',
        'static/settings/outcome-analyzer-insights-visible.png',
        'static/settings/saved-ranges-1.png',
        'static/settings/saved-ranges-2.png',
        'static/settings/saved-ranges-3.png',
        'static/settings/saved-ranges-4.png',
        'static/settings/included-selectors/double-slider-selector.png',
        'static/settings/included-selectors/log-double-slider-selector.png',
        'static/settings/included-selectors/saved-ranges-selector.png',
        'static/settings/included-selectors/single-slider-selector.png',
        'static/settings/included-selectors/tier-and-category-selector.png',
        'static/settings/tiers/tiers.png',
        'static/settings/visual/dont-show-num-combos-in-range.png',
        'static/settings/visual/green-grid-squares.png',
        'static/settings/visual/multicolored-grid-squares.png',
        'static/settings/visual/show-num-combos-in-range.png',
      ]).then(function () {
        console.log('Successfully cached everything.')
      }).catch(function (error) {
        console.log('Problem caching: ', error);
      });

      return promise;
    }).catch(function () {
      console.error('Error with caches.open or cache.addAll');
    })
  );
});

self.addEventListener('activate', function(event) {
  console.log('activate');
  event.waitUntil(
    caches.keys()
      .then(function getOldCachesThatBeginWithPremiumPokerToolsDash (cacheNames) {
        console.log(cacheNames);
        return cacheNames.filter(function (cacheName) {
          return cacheName.startsWith('premium-poker-tools-') && (cacheName !== currCacheName);
        });
      })
      .then(function removeOldCachesThatBeginWithPremiumPokerToolsDash (oldCachesThatBeginWithPremiumPokerToolsDash) {
        console.log(oldCachesThatBeginWithPremiumPokerToolsDash)
        let removeCachePromises = [];

        oldCachesThatBeginWithPremiumPokerToolsDash.forEach(function (oldCacheThatBeginsWithPremiumPokerToolsDash) {
          removeCachePromises.push(caches.delete(oldCacheThatBeginsWithPremiumPokerToolsDash));
        });

        console.log(removeCachePromises);
        return Promise.all(removeCachePromises);
      })
  );
});

self.addEventListener('fetch', function(event) {
  console.log('fetch');
  event.respondWith(
    caches.match(event.request).then(function (response) {
      if (response) {
        return response;
      }

      return fetch(event.request);
    }).catch(function () {
      console.error('Error trying to match event request to cache.');
    })
  );
});

The issue comes when I am in a state where I have a service worker installed and active, and I have all of my stuff cached. When I have the dev tools open and have "update on reload" checked in Chrome, if I reload:

  • The page looks the same, but has the spinner indicating that it is still loading.
  • In the dev tools, it shows that a new service worker is "waiting to activate".
  • In the network tab, it shows that the request to http://localhost:8080/ is continually pending.
  • "Successfully cached everything." is the only thing that gets logged to the console. "activate" doesn't get logged, and neither does "fetch".

But if I press the "x" in Chrome to tell it to stop loading, and then refresh again, it loads perfectly.

I can't seem to figure out what is wrong. / is in the premium-poker-tools-1 cache, so shouldn't the request hit the service worker and return the cached HTML? And even if it doesn't find it there, shouldn't it be sending a request out to the server to get the response? How is it getting hung up?

Edit: I now understand that the service worker is replaced when "Update on reload" is checked even if the service worker hasn't changed.

1
javascriptservice-worker
"update on reload" tells chrome to update the service worker every time you reload the page, hence why you see it updating every time... – miknik
@miknik I see. Thanks for clarifying. – Adam Zerner
Have you set History to "Never Remember Anything"? If so, page w service worker will never load. – Ronnie Royston
@RonRoyston I'm not familiar with that setting. Would you mind letting me know where it is so I can check it's state? – Adam Zerner
@AdamZerner Can't find it in Chrome but in Firefox it's about:preferences#privacy. I remember I had this problem once recently. Also, take care that you're not in 'offline mode' bcs that disallows your browser from fetching/loading/initializing the service worker if it was deleted/not installed before going to offline mode. Hope that helps... – Ronnie Royston

1 Answers

0
votes

This answer is moved from the bottom of the question, to make it clearer what the underlying issue is:

I now understand that the service worker is replaced when "Update on reload" is checked even if the service worker hasn't changed.