UUID

[jakearchibald]

UUIDs seem to be the best way to express equality between instances of a concept, especially if that data lives between browser restarts.

Is this worth having in infra?

[annevk]

Yeah, it might be worth doing a survey to see where UUID is used as a primitive and what characteristics are assumed. And then define it and provide some guidance around it.

Service workers also expose it, right? And I think File API does too. Might be good to have serialization requirements too then.

[jakearchibald]

Service worker uses https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-id and exposes it via https://w3c.github.io/ServiceWorker/#dom-client-id.

I'm looking to use it in background fetch to distinguish instances of https://wicg.github.io/background-fetch/#background-fetch-concept, but it won't be exposed.

[annevk]

https://w3c.github.io/FileAPI/#ABNFUUID has a whole ABNF. I wonder if that's actually implemented as such though.

[annevk]

mozilla/standards-positions#511 (comment) by @bcoe lists some more places. Perhaps that specification can become the central point of reference though.

[jakearchibald]

Related: In the session history PR I'm introducing the idea of a unique internal value https://whatpr.org/html/6315/common-microsyntaxes.html#unique-values