*Contact emails* pmee...@chromium.org *Explainer* https://docs.google.com/document/d/1uAutnUWpC6V-ka_MA-4m74YV12LAA6qP1sYjy97S2-0/edit?usp=sharing
*Specification* https://github.com/httpwg/http-extensions/issues/2649 *Design docs* https://docs.google.com/document/d/1uAutnUWpC6V-ka_MA-4m74YV12LAA6qP1sYjy97S2-0/edit?usp=sharing *Summary* Adds support for an explicit time-to-live for dictionaries used in Compression Dictionary Transport. This is a backward-compatible extension to the "Use-As-Dictionary" HTTP response header that adds a "ttl" parameter. The ttl is the number of seconds after the dictionary was last fetched that it is usable as a compression dictionary and overrides the default expiration (which is to expire when the underlying resource expires from the HTTP cache). For example: Use-AsDictionary: match="/*", ttl=600 Would make the response available as a compression dictionary for 10 minutes independent of the HTTP caching headers. This capability was part of the original feature but dropped during the standards process because of a lack of compelling use cases at the time. New use cases have emerged as the feature gains adoption that make it useful to add as an extension. *Blink component* Blink>Network <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ENetwork%22> *Web Feature ID* compression-dictionary-transport <https://webstatus.dev/features/compression-dictionary-transport> *TAG review* None *TAG review status* Pending *Risks* *Interoperability and Compatibility*This feature is backwards-compatible with the existing compression dictionary transport spec. Browsers that do not implement support for "ttl" will fall back to using the cache lifetime of the response. *Gecko*: No signal *WebKit*: No signal *Web developers*: No signals *Other signals*: *Security*The "ttl" can only extend the lifetime of a dictionary for responses that are otherwise cacheable but with a short (or zero) max-age. Responses that are not allowed to be stored in the HTTP cache (no-store or no-cache) will still not be used as a dictionary and can not be extended. *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 *Goals for experimentation* Explore the usefulness of an explicit dictionary lifetime to see if it adds enough value to justify adding it as an extension to the Compression Dictionary Transport spec. *Ongoing technical constraints* None *Debuggability* None *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 *Flag name on about://flags* enable-compression-dictionary-ttl *Finch feature name* CompressionDictionaryTTL *Requires code in //chrome?* False *Estimated milestones* DevTrial on desktop 142 DevTrial on Android 142 *Link to entry on the Chrome Platform Status* https://chromestatus.com/feature/6408307086589952 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 visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAPq58w70PvZzw%2BxM_RhGRa78nxtcSgq9UVvVaFYRSgQJ%3Dfkpzg%40mail.gmail.com.
