Thanks for getting the spec PR landed, and for the clarifications on when the preload will be triggered. LGTM1.
-- Dan On Sunday, July 27, 2025 at 10:06:56 PM UTC-7 yyana...@chromium.org wrote: > > > 2025年7月28日(月) 13:05 Shunya Shishido <sisid...@chromium.org>: > >> >> >> On Fri, Jul 25, 2025 at 2:37 PM Yoshisato Yanagisawa < >> yyana...@chromium.org> wrote: >> >>> >>> >>> 2025年7月25日(金) 10:44 'Daniel Clark' via blink-dev <blin...@chromium.org>: >>> >>>> This looks like a nice optimization. >>>> >>>> > Specification >>>> > https://github.com/w3c/ServiceWorker/pull/1756 >>>> >>>> What needs to happen for this PR to land? It looks like there are a >>>> couple minor things from 2 weeks ago that need to be addressed. Since the >>>> WebKit reviewer has now approved, could it be landed after that? >>>> >>> >>> I am a reviewer of the PR, and the remaining part is addressing comments >>> there. >>> >> Comments were resolved, I believe now it's ready to be landed. >> >> > > Thank you. LGTM, merged. > > >> >>> >>>> Regarding a site's eligibility for the feature -- could you clarify the >>>> criteria you plan to ship with? The explainer section at >>>> https://github.com/WICG/service-worker-auto-preload?tab=readme-ov-file#eligibility-criteria >>>> seems >>>> to have been written before the experiment >>>> <https://github.com/WICG/service-worker-auto-preload/issues/3>, so I'm >>>> curious as to whether your thinking on that is still the same. >>>> >>> >>> Upon the PR, there are no additional criteria needed. Network requests >>> may always be sent if the feature is not explicitly disabled. >>> I hope @Shunya Shishido to explain the details. >>> >> Yes. The spec says that a user agent may dispatch a network request >> unless there is an opt-out >> <https://github.com/WICG/service-worker-auto-preload?tab=readme-ov-file#opt-out> >> >> signal via the static routing API. In Chrome, based on the previous >> experiment result >> <https://github.com/WICG/service-worker-auto-preload/issues/3>, we'll >> enable this optimization when the service worker is not running. In the >> future, we may want to implement another criteria such as higher rates of >> fetch handler results are fallback for further optimization. >> >> >>> >>> >>>> Also, point (1) there is not so clear :"Higher rates of fetch handler >>>> results are fallback." Is there a specific rate you have in mind, and how >>>> is that determined? >>>> >>> Again we'll enable this when the service worker is not running. For the >> fetch handler fallback rate, we don't have this mechanism yet, and we need >> another study to determine the threshold. But we believe it's worth >> exploring in the future since there are so many sites using service workers >> and the main resource fetch handler results are always fallback. >> >> Have you talked to the WebKit folks to see what eligibility criteria they >>>> plan to use for their version of the feature? >>>> >>> Yes. I understand their criteria is also when the service worker is not >> running. Please check this comment >> <https://github.com/WICG/proposals/issues/155#issuecomment-2873318636>. >> >> >>> >>>> -- Dan >>>> >>>> ------------------------------ >>>> *From:* Shunya Shishido <sisid...@chromium.org> >>>> *Sent:* Wednesday, July 23, 2025 12:54 AM >>>> *To:* blink-dev <blin...@chromium.org> >>>> *Subject:* [EXTERNAL] [blink-dev] Intent to Ship: >>>> ServiceWorkerAutoPreload >>>> >>>> You don't often get email from sisid...@chromium.org. Learn why this >>>> is important <https://aka.ms/LearnAboutSenderIdentification> >>>> Contact emails >>>> sisid...@chromium.org >>>> >>>> Explainer >>>> https://github.com/WICG/service-worker-auto-preload >>>> >>>> Specification >>>> https://github.com/w3c/ServiceWorker/pull/1756 >>>> >>>> Summary >>>> >>>> ServiceWorkerAutoPreload is a mode where the browser issues the network >>>> request in parallel with the service worker bootstrap, and consumes the >>>> network request result inside the fetch handler if the fetch handler >>>> returns the response with `respondWith()`. If the fetch handler result is >>>> fallback, it passes the network response directly to the browser. >>>> ServiceWorkerAutoPreload is defined as an optional browser optimization, >>>> which will change the existing service worker behavior. We expect the >>>> impact on Enterprise is low, but the temporary enterprise policy called >>>> ServiceWorkerAutoPreloadEnabled will be added to control this feature. >>>> >>>> >>>> Blink component >>>> Blink>ServiceWorker >>>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EServiceWorker%22> >>>> >>>> TAG review >>>> https://github.com/w3ctag/design-reviews/issues/1108 >>>> https://github.com/w3ctag/design-reviews/issues/963 >>>> >>>> TAG review status >>>> Pending >>>> >>>> Risks >>>> >>>> >>>> Interoperability and Compatibility >>>> >>>> For compatibility risks, the main concern was about how this feature >>>> works with the navigation preload API. But we don't think this feature >>>> introduces major compatibility issues because this feature respects the >>>> navigation preload API, and is not exposed when the navigation preload API >>>> is already enabled. The only cost is the server side cost to respond to >>>> the >>>> network requests, which may not be used if the fetch handler returns a >>>> result from the disk cache. This cost can be reduced by applying the >>>> feature only when the service worker is not started, or only for websites >>>> that meet some criteria e.g. fetch handler always fallback to the network. >>>> >>>> >>>> *Gecko*: No signal ( >>>> https://github.com/mozilla/standards-positions/issues/1036) >>>> >>>> *WebKit*: No signal ( >>>> https://github.com/WebKit/standards-positions/issues/359) Although we >>>> are still waiting for WebKit's official standard position, we believe they >>>> are supportive. A reply on the proposal mentioned that it 'seems inline >>>> with what WebKit is implementing,' and a WebKit reviewer has already >>>> approved our spec change PR. >>>> https://github.com/WICG/proposals/issues/155#issuecomment-2873318636 >>>> https://github.com/w3c/ServiceWorker/pull/1756 >>>> >>>> *Web developers*: No signals >>>> >>>> *Other signals*: >>>> >>>> WebView application risks >>>> >>>> *Does this intent deprecate or change behavior of existing APIs, such >>>> that it has potentially high risk for Android WebView-based applications?* >>>> >>>> None >>>> >>>> >>>> Debuggability >>>> >>>> We have a plan to show some info when the preload requests by this >>>> feature are triggered on DevTools. It's tracked in crbug.com/344912796 >>>> >>>> >>>> Will this feature be supported on all six Blink platforms (Windows, >>>> Mac, Linux, ChromeOS, Android, and Android WebView)? >>>> Yes >>>> >>>> Is this feature fully tested by web-platform-tests >>>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >>>> ? >>>> No >>>> >>>> Currently we don't have WPT tests. As this feature is only exposed with >>>> heuristics and it doesn't have an API surface, it's not testable on the >>>> WPT >>>> infrastructure. >>>> >>>> >>>> Flag name on about://flags >>>> service-worker-auto-preload >>>> >>>> Finch feature name >>>> ServiceWorkerAutoPreload >>>> >>>> Rollout plan >>>> Will ship enabled for all users >>>> >>>> Requires code in //chrome? >>>> False >>>> >>>> Tracking bug >>>> https://crbug.com/40278676 >>>> >>>> Estimated milestones >>>> >>>> Shipping on desktop >>>> 140 >>>> Origin trial desktop first >>>> 131 >>>> Origin trial desktop last >>>> 136 >>>> DevTrial on desktop >>>> 126 >>>> Shipping on Android >>>> 140 >>>> Origin trial Android first >>>> 131 >>>> Origin trial Android last >>>> 136 >>>> DevTrial on Android >>>> 126 >>>> Shipping on WebView >>>> 140 >>>> >>>> >>>> Anticipated spec changes >>>> >>>> *Open questions about a feature may be a source of future web compat or >>>> interop issues. Please list open issues (e.g. links to known github issues >>>> in the project for the feature specification) whose resolution may >>>> introduce web compat/interop risk (e.g., changing to naming or structure >>>> of >>>> the API in a non-backward-compatible way).* >>>> None >>>> >>>> Link to entry on the Chrome Platform Status >>>> https://chromestatus.com/feature/5194817700364288?gate=6249384911306752 >>>> >>>> Links to previous Intent discussions >>>> Intent to Prototype: >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGMyg-btkw3n_k0Vr9GgW%2B_c%2BT5K%3D_1_BPFstqAVi0y%3DxxT-pg%40mail.gmail.com >>>> Intent to Experiment: >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGMyg-YF1qRNkBUPGxN-GgDGG3yvqCijZ56QEQYgNA4a9YrfMg%40mail.gmail.com >>>> >>>> >>>> This intent message was generated by Chrome Platform Status >>>> <https://chromestatus.com/>. >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "blink-dev" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to blink-dev+...@chromium.org. >>>> To view this discussion visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGMyg-YGDFiHciHb701OhxBf3QUQbs-11o%2BjY03AAxvrrYmxow%40mail.gmail.com >>>> >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGMyg-YGDFiHciHb701OhxBf3QUQbs-11o%2BjY03AAxvrrYmxow%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "blink-dev" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to blink-dev+...@chromium.org. >>>> To view this discussion visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CH4PR00MB23298ED82DCB351D28A07555C559A%40CH4PR00MB2329.namprd00.prod.outlook.com >>>> >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CH4PR00MB23298ED82DCB351D28A07555C559A%40CH4PR00MB2329.namprd00.prod.outlook.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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