Thanks for working on this, as I'm enthusiastically supportive of tackling this use case!
One thing I wish y'all have done, and that I haven't seen any evidence of (but please correct me if I'm wrong) is discuss this design with the HTTPWG at the IETF. That is feedback that I believe you got at TPAC 22, as well as on the TAG review. While this is not strictly blocking this intent (as the prefetch cache is a web concept), as the explainer rightfully states, this is a concept that can very well be expanded to encompass HTTP caches, both inside and outside the browser. It'd be great if that eventual expansion is compatible with the prefetch cache. Would y'all be open to bringing the design to discussion at the HTTPWG, and potentially move the header's semantic definition there? (while eventually moving the web processing model to a web standards venue) +David Schinazi <dschin...@google.com> for his thoughts on the above On Wed, Nov 8, 2023 at 4:20 PM Daniel Bratell <bratel...@gmail.com> wrote: > LGTM2 > > /Daniel > On 2023-11-07 01:57, Mike Taylor wrote: > > Thanks Liviu. > > I've spent some time today reviewing the explainer and spec, and find the > use cases compelling. > > LGTM1 to ship. A non-blocking request would be to add the security & > privacy considerations from the explainer into the draft WICG spec (or > something similar). > > (Also, kudos to all who contributed to the explainer - it's very thorough > and answered every question I had as I began to review in depth. Excellent > work.) > On 11/6/23 5:08 PM, Liviu Tinta wrote: > > > Are there any open issues that would result in breaking changes, after > we ship? > > There are 2 open issues related to No-Vary-Search: > https://github.com/WICG/nav-speculation/labels/no-vary-search. None of > the open issues requires modifying No-Vary-Search header. We are not > expecting breaking changes after we ship. > > On Monday, November 6, 2023 at 1:43:06 PM UTC-5 Mike Taylor wrote: > >> On 11/1/23 9:59 AM, Liviu Tinta wrote: >> >> Contact emails dome...@chromium.org, jbro...@chromium.org, >> liviuti...@chromium.org >> >> Explainer >> https://github.com/WICG/nav-speculation/blob/main/no-vary-search.md >> >> Specification https://wicg.github.io/nav-speculation/no-vary-search.html >> >> Summary >> >> Enables prefetch to match even if URL query parameters change. The >> No-Vary-Search HTTP response header declares that some or all parts of a >> URL's query can be ignored for cache matching purposes. It can declare that >> the order of query parameter keys should not cause cache misses, that >> specific query parameters should not cause cache misses or that only >> certain known query parameters should cause cache misses. It could apply to >> multiple caches, but this entry refers to support for prefetch cache. >> >> We would like to ship "No-Vary-Search support in navigation prefetch >> cache" together with "No-Vary-Search Hint for Prefetch Speculation >> Rules" (https://chromestatus.com/feature/4887338302308352). >> >> Blink component Internals>Preload >> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Internals%3EPreload> >> >> TAG review https://github.com/w3ctag/design-reviews/issues/797 >> >> TAG review status Positive. >> >> Chromium Trial Name NoVarySearchPrefetch >> >> Link to origin trial feedback summary >> https://github.com/WICG/nav-speculation/issues >> >> Are there any open issues that would result in breaking changes, after we >> ship? >> >> >> Origin Trial documentation link >> https://developer.chrome.com/origintrials/#/view_trial/4146689356901384193 >> >> Risks >> >> >> Interoperability and Compatibility >> >> *Gecko*: No signal ( >> https://github.com/mozilla/standards-positions/issues/717) >> >> *WebKit*: No signal ( >> https://github.com/WebKit/standards-positions/issues/106) >> >> *Web developers*: Google Search has been experimenting with No-Vary-Search >> header / Speculation Rules "expects_no_vary_search". This functionality >> helps Google Search to match prefetched content to the next user >> navigation. Developers can use parameters in the prefetched URL that are >> not needed when navigating to the actual link (e.g. the source of the link >> click). The server can customize behavior using these parameters without >> causing a cache miss in the browser. >> "expects_no_vary_search" addition to Speculation Rules allows the browser >> to completely handle the case where the user navigates to a URL that is >> currently prefetched by waiting for the ongoing prefetch instead of >> directly requesting the page from the server. >> Google Search conducted experiments prefetching Search results pages from >> the search box and other links that lead to another Search results page. >> There was significant latency improvement for navigating to Search result >> pages prefetched using No-Vary-Search header and "expects_no_vary_search". >> >> *Other signals*: No-Vary-Search header has been discussed, together with >> No-Vary-Search Hint for Prefetch Speculation Rules at Web Perf WG >> meeting at TPAC 2023 >> <https://docs.google.com/presentation/d/1GK92nCORW5vKd7LgGtTsgy35eqTV7P71l05pHsni8ok/edit#slide=id.g240fd6541f7_0_31> >> . >> >> Ergonomics >> >> No-Vary-Search will be used in tandem with Speculation Rules ( >> https://wicg.github.io/nav-speculation/speculation-rules.html). The >> default usage of No-Vary-Search will not make it hard for Chrome to >> maintain good performance. >> >> >> Activation >> >> It will not be challenging for developers to take advantage of this >> feature immediately. >> >> >> Security >> >> See: >> https://github.com/WICG/nav-speculation/blob/main/no-vary-search-security-privacy-questionnaire.md >> >> >> 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 website owner can debug the feature in DevTools by making sure that, >> when navigating to a prefetched page by using a URL that matches under >> No-Vary-Search conditions, the navigation happens from the prefetch cache >> by looking at the Size column in the Network tab. In case of success, when >> hovering over the Size column in the Network tab of Dev Tools, they should >> see: "Served from prefetch cache, resource size: yyyB". >> >> No-Vary-Search header value for the prefetch is available on the Network >> tab. Developers can also use the preloading panel ( >> https://crbug.com/1361483) which shows all ongoing preloads. >> >> >> Will this feature be supported on all six Blink platforms (Windows, Mac, >> Linux, Chrome OS, 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> >> ? Yes >> >> >> https://wpt.fyi/results/speculation-rules/prefetch/no-vary-search?label=experimental&label=master&aligned >> >> >> Flag name on chrome://flags >> >> Finch feature name NoVarySearchPrefetch >> >> Requires code in //chrome? False >> >> Tracking bug >> https://bugs.chromium.org/p/chromium/issues/detail?id=1378075 >> >> Non-OSS dependencies >> >> Does the feature depend on any code or APIs outside the Chromium open >> source repository and its open-source dependencies to function? >> No. >> >> Estimated milestones >> Shipping on desktop 121 >> OriginTrial desktop last 120 >> OriginTrial desktop first 110 >> DevTrial on desktop 110 >> Shipping on Android 121 >> OriginTrial Android last 120 >> OriginTrial Android first 110 >> DevTrial on Android 110 >> Shipping on WebView 121 >> OriginTrial webView last 120 >> OriginTrial webView first 110 >> >> 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/5071247189213184 >> >> Links to previous Intent discussions Intent to prototype: >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHaAqYKutrvgMxR%3DnfAQOfBHNJo9ifrmFRSbiE0heDyeW0uKJA%40mail.gmail.com >> >> Intent to Experiment: >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHaAqYLGT%2BV3_u_oumjHCZD05RRYY5guMjz1vb7501sNF1CANg%40mail.gmail.com >> Intent to Extend Experiment: >> https://groups.google.com/a/chromium.org/g/blink-dev/c/7oMlGWmVv2Q/m/B2PACBSnBgAJ >> >> -- >> 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/CAHaAqYKL2psmkYpQQ6KjrM_41yt8f%3DvH_-m0%3DT4idWT4zSumHw%40mail.gmail.com >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHaAqYKL2psmkYpQQ6KjrM_41yt8f%3DvH_-m0%3DT4idWT4zSumHw%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+unsubscr...@chromium.org. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/b878e749-5d1a-4205-8612-3bd36db82fb3%40chromium.org > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/b878e749-5d1a-4205-8612-3bd36db82fb3%40chromium.org?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+unsubscr...@chromium.org. > To view this discussion on the web visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/265d9c2a-08fc-4ee8-b1ec-f125a910c91f%40gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/265d9c2a-08fc-4ee8-b1ec-f125a910c91f%40gmail.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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