Support wasi-keyvalue

[endocrimes]

wasi-keyvalue is relatively complete as an interface and the core interface (https://github.com/WebAssembly/wasi-keyvalue/blob/main/wit/store.wit) is almost identical to spin-kv (https://github.com/fermyon/spin/blob/main/wit/key-value.wit) with the primary difference being the exists function.

We should add support for wasi-keyvalue to get broader ecosystem compatibility - and the ability to benefit from the extended interfaces over time.

[itowlson]

@endocrimes Can you expand on the difference you identified around the exists function please? They look the same to me but I'm not terribly au fait with the wasi-keyvalue side.

(The main difference I did run into was around list-keys accepting a cursor for paging.)

[endocrimes]

Past me forgot to link to a revision, but that got added since I last looked 😅 - now there's no meaningful difference 🎉

[mikkelhegn]

@itowlson - We talked about this in today's Spin Up meeting. There is a release going out early next week. If there is an opporutnity to get this in, it's possible. If not, we can move it to post release in the board.

[itowlson]

@mikkelhegn There is a PR out. The first step towards a release would be to get feedback on that, specifically on the critical question of how to manage the Spin world versioning. I'll ping the reviewers.

[lann]

the critical question of how to manage the Spin world versioning

Notably, this is basically the entire focus of WASI 0.2.1 and afaik we still haven't even completely figured out versioning for that upstream.

[itowlson]

@mikkelhegn given ^^ I think it is fair to say this will not be part of 2.6