It's probably also worth noting that adding encodings to the compression streams API would require browsers to bundle the compression code for the relevant encodings (where they only pull in the decompression code for network-level content encodings).
Not saying the discussions shouldn't happen, just that they are separate discussions that should have the appropriate use cases and justifications laid out. On Tue, Sep 26, 2023 at 1:54 PM Patrick Meenan <pmee...@chromium.org> wrote: > We had put the compression stream API out of scope > <https://github.com/WICG/compression-dictionary-transport#compression-api> > for the dictionary work because the dictionaries would require a different > constructor that allows for specifying the dictionary bytes (or stream). > That's independent of supporting zstd and br on the compression streams API > itself though (which would be necessary to add dictionary support). > > On Tue, Sep 26, 2023 at 1:17 PM Alex Russell <slightly...@chromium.org> > wrote: > >> Hey folks, >> >> Glad to see there's excitement around the OT; was wondering if there has >> been any work to extend Compression Streams for zstd as part of this >> effort? I don't see it in the explainer, and it would be great for us not >> to be adding new ecodings that aren't also exposed to userland. >> >> Best, >> >> Alex >> >> On Thursday, August 3, 2023 at 9:23:13 PM UTC-7 Tsuyoshi Horo wrote: >> >>> Hi, blink-dev@ members. >>> >>> The origin trial for the new CompressionDictionaryTransport feature is >>> now available in the Origin Trial console at: >>> https://developer.chrome.com/origintrials/ >>> >>> We have also published a document that provides more information about >>> the feature and how to participate in the trial. The document can be found >>> here: >>> >>> https://chromium.googlesource.com/chromium/src/+/main/docs/experiments/compression-dictionary-transport.md >>> >>> We hope this information is helpful. Please let us know if you have any >>> questions. >>> >>> Thanks. >>> >>> >>> On Thu, Jul 27, 2023 at 12:29 AM Mike Taylor <miketa...@chromium.org> >>> wrote: >>> >>>> LGTM to experiment from 117 to 122 inclusive. >>>> >>>> (Good luck, looks cool!) >>>> On 7/25/23 9:52 PM, Tsuyoshi Horo wrote: >>>> >>>> Contact emails h...@chromium.org, pmee...@chromium.org, >>>> yoavwe...@chromium.org, kenjibah...@chromium.org >>>> >>>> Explainer https://github.com/WICG/compression-dictionary-transport >>>> >>>> Specification https://github.com/WICG/compression-dictionary-transport >>>> >>>> Design docs >>>> >>>> https://docs.google.com/document/d/1IcRHLv-e9boECgPA5J4t8NDv9FPHDGgn0C12kfBgANg/edit >>>> https://github.com/WICG/compression-dictionary-transport >>>> >>>> https://datatracker.ietf.org/doc/draft-meenan-httpbis-compression-dictionary >>>> >>>> Summary >>>> >>>> This feature adds support for using designated previous responses, as >>>> an external dictionary for Brotli-compressing HTTP responses. >>>> >>>> >>>> Blink component Blink>Network >>>> <https://bugs.chromium.org/p/chromium/issues/list?q=component:Blink%3ENetwork> >>>> >>>> TAG review https://github.com/w3ctag/design-reviews/issues/877 >>>> >>>> TAG review status Pending >>>> >>>> Risks >>>> >>>> >>>> Interoperability and Compatibility >>>> >>>> Interoperability and Compatibility risk are low. This feature >>>> introduces a new compression method for transporting resources over HTTP. >>>> Web sites can know the browser support for the new feature by checking >>>> `document.createElement('link').relList.supports('dictionary')`. Also web >>>> servers can know the browser support by checking the `Accept-Encoding` >>>> request header and the new `Use-As-Dictionary` request header. This feature >>>> is an opt-in feature. And the dictionary storage is isolated using the top >>>> level site and the frame origin as the key. That means, if there is no >>>> dictionary registered for the site, the behavior of Chrome will not change >>>> while browsing the site. Also this feature is usable only on >>>> secure-context. So this feature will not increase the risk of >>>> non-supporting network proxies misunderstanding the content’s encoding. >>>> >>>> >>>> *Gecko*: Positive ( >>>> https://github.com/mozilla/standards-positions/issues/771) >>>> >>>> *WebKit*: No signal ( >>>> https://github.com/WebKit/standards-positions/issues/160) >>>> >>>> *Web developers*: No signals >>>> >>>> *Other signals*: >>>> >>>> Ergonomics >>>> >>>> To reduce memory usage in network services, dictionary metadata is >>>> stored in a database on disk. And to avoid performance degradation for >>>> normal requests that do not use a dictionary, the reading of this metadata >>>> is designed not to block network requests. In other words, if the reading >>>> of metadata from the database is not completed before the request header is >>>> ready to be sent to the server, the dictionary may not be used even if it >>>> is already registered in the database. >>>> >>>> >>>> Activation >>>> >>>> To adopt this feature, web developers need to make changes in their web >>>> servers. Currently there is no major server softwares which supports >>>> compression dictionaries. >>>> >>>> >>>> Security >>>> >>>> Chrome registers the response as a dictionary only when the response is >>>> CORS-readable from the document origin. Also we use a registered dictionary >>>> to decompress the response only when the response is CORS-readable from the >>>> document origin. Additionally, the dictionary and the compressed resource >>>> are required to be from the same origin as each other. So this should not >>>> introduce any new attack vector of stealing information. The dictionaries >>>> are partitioned with the storage cache and are cleared whenever cookies or >>>> cache is cleared to ensure that the dictionaries can not be abused as a >>>> tracking vector. >>>> >>>> >>>> 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? >>>> >>>> >>>> Goals for experimentation We would like to collect feedback on the >>>> Compression Dictionary Transport feature of API design. We would also like >>>> to run some experiments using this feature to measure its performance >>>> impact. >>>> >>>> Ongoing technical constraints >>>> >>>> None >>>> >>>> >>>> Debuggability >>>> >>>> We have introduced chrome://net-internals/#sharedDictionary. Using it, >>>> web developers can manage the registered dictionaries. Also web developers >>>> can check the related HTTP request and response headers (Use-As-Dictionary, >>>> Sec-Available-Dictionary, Accept-Encoding, Content-Encoding) using >>>> DevTools' Network tab. >>>> >>>> >>>> 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> >>>> ? No. We will rewrite some browser_tests to WPT. >>>> >>>> Flag name on chrome://flags >>>> chrome://flags/#enable-compression-dictionary-transport-backend >>>> chrome://flags/#enable-compression-dictionary-transport >>>> >>>> Finch feature name CompressionDictionaryTransportBackend >>>> CompressionDictionaryTransport >>>> >>>> Requires code in //chrome? True >>>> >>>> Tracking bug https://crbug.com/1413922 >>>> >>>> Launch bug https://launch.corp.google.com/launch/4266286 >>>> >>>> Estimated milestones >>>> OriginTrial desktop last 122 >>>> OriginTrial desktop first 117 >>>> OriginTrial Android last 122 >>>> OriginTrial Android first 117 >>>> >>>> Link to entry on the Chrome Platform Status >>>> https://chromestatus.com/feature/5124977788977152 >>>> >>>> Links to previous Intent discussions Intent to prototype: >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADk0S-Vb1ON2XT2%2BBP27tJ4ivjgyu63jcd667am4TwcVFGsbuw%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+unsubscr...@chromium.org. >>>> To view this discussion on the web visit >>>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADk0S-WyukWVPpFMFYSWVZ1%2BOuXVjtNfWiCqKvDYcdRwaApZLA%40mail.gmail.com >>>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CADk0S-WyukWVPpFMFYSWVZ1%2BOuXVjtNfWiCqKvDYcdRwaApZLA%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/CAPq58w5yGbTOKXbXFMLVQULb8JZYY1um1CAgTDH2wm5rBR7jAw%40mail.gmail.com.
