Feature: WASI Preview 2 Support

[nickchomey]

Feature description

As best as I can tell, WASI Preview 2 is now the official version of WASI, while Preview 1 was moved to the legacy directory in their repo.

They marked the first official release (0.2.0) of WASI on April 24, 2024, which corresponds with Preview 2.

It has APIs defined for HTTP, filesystem and more - which would be very useful in general, and for a Benthos processor in particular (which we discussed here).

So, it would be great if Conduit Processor SDK could move to support the Preview 2 APIs.

[hariso]

Thanks for the issue @nickchomey ! It seems to me that we need to wait for the support in Go first: golang/go#65333.

[nickchomey]

Ah, I wasn't aware. Well, at least this issue can serve as a reminder/tracker for progress there.

[hariso]

Yup, definitely good to have a tracker issue!

[lovromazgon]

I moved this issue to the main Conduit repo, as the WASI Preview 2 support needs to be added on the host (i.e. Conduit).

[nickchomey]

This seems to be very promising progress. Could it be used to make a tinygo wasm component out of, say, Benthos and then include as a processor in conduit somehow?

https://wasmcloud.com/blog/compile-go-directly-to-webassembly-components-with-tinygo-and-wasi-p2

[nickchomey]

I looked a bit more into this and, of course, while this is progress you still need a wasm implementation that handles wasi preview 2. According to WASI, only wasmtime and jco do.

https://github.com/WebAssembly/WASI/blob/main/preview2/README.md#wasi-preview-2-implementations

I've created an issue at wazero to add support for wasip2 tetratelabs/wazero#2289

An alternative would be using wasmtime-go, but i assume you're not interested as it isn't pure Go, like wazero https://github.com/bytecodealliance/wasmtime-go

[nickchomey]

Well, Wazero made it extremely clear there that they have no intention to support any further WASI previews until it reaches 1.0 and is in W3C spec. Not sure if/how that affects Conduit's plans

[hariso]

Well, some of the features that are introduced in Preview 2 are really handy, such as HTTP. We're currently focusing on schema support in Conduit, but the team will discuss this when we are done with it. Thanks for looking into this and brining this up @nickchomey !