Contact emailsdome...@chromium.org, jbro...@chromium.org, liviuti...@chromium.org
Explainer https://github.com/WICG/nav-speculation/blob/main/triggers.md#no-vary-search-hint <https://wicg.github.io/nav-speculation/prerendering.html> Specificationhttps://wicg.github.io/nav-speculation/prerendering.html Summary Adds a hint to speculation rules that informs the navigation prerender cache that the URL to be prerendered expects to receive the same No-Vary-Search header in the response. The hint is useful because prerenders that depend on No-Vary-Search to match to navigations do not benefit the user if the navigation happens before prerender headers return from the server. Using the hint, the web browser will expect, but verify, that the No-Vary-Search hint matches with the No-Vary-Search header. If the No-Vary-Search hint does not match the No-Vary-Search header received then the web browser will send a new request. Blink componentInternals>Preload>Prerender <https://bugs.chromium.org/p/chromium/issues/list?q=component:Internals%3EPreload%3EPrerender> Motivation Adds a hint to speculation rules that informs the navigation prerender cache that the URL to be prerendered expects to receive the same No-Vary-Search header in the response. The hint is useful because prerenders that depend on No-Vary-Search to match to navigations do not benefit the user if the navigation happens before prerender headers return from the server. Using the hint, the web browser will expect, but verify, that the No-Vary-Search hint matches with the No-Vary-Search header. If the No-Vary-Search hint does not match the No-Vary-Search header received then the web browser will send a new request. Initial public proposal https://github.com/WICG/nav-speculation/blob/main/triggers.md#no-vary-search-hint <https://wicg.github.io/nav-speculation/prerendering.html> TAG reviewNot applicable. The TAG has already given a negative opinion on the overall complexity of speculation rules ( https://github.com/w3ctag/design-reviews/issues/721), so we anticipate it would not be a good use of their time to review additions to the syntax. The addition itself is small and any architectural questions about it would be covered under the general closed speculation rules review. TAG review statusNot applicable. Risks Interoperability and Compatibility None *Gecko*: No signal *WebKit*: No signal *Web developers*: No signals *Other signals*: No-Vary-Search Hint for Prefetch Speculation Rules has been discussed, together with No-Vary-Search header at Web Perf WG meeting at TPAC 2023 <https://docs.google.com/presentation/d/1GK92nCORW5vKd7LgGtTsgy35eqTV7P71l05pHsni8ok/edit#slide=id.g240fd6541f7_0_31>. This feature implements the same No-Vary-Search Hint behaviour for prerender Speculation Rules. 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 The No-Vary-Search hint is represented as a new json attribute ("expects_no_vary_search") in prerender Speculation Rules. The Speculation Rules can be viewed in DevTools on the Application tab under Speculative loads->Rules. Is this feature fully tested by web-platform-tests <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> ?Yes, Web Platform Tests will be added. Flag name on chrome://flagsNone Finch feature namePrerender2NoVarySearch - shared with No-Vary-Search support for Prerender <https://chromestatus.com/feature/5099218903760896?gate=6293413152686080> Non-finch justificationNone Requires code in //chrome?False Estimated milestones No milestones specified Link to entry on the Chrome Platform Status https://chromestatus.com/feature/5190922953555968?gate=5169870617706496 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+unsubscr...@chromium.org. To view this discussion on the web visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHaAqYLUJmP7s2u%3DZ8UtMhV-ZviMSievv2eN2S4GgrkgFdg%3DrA%40mail.gmail.com.
