Webrtc wasm-ext

[DougAnderson444]

Description

Beginning of exploring an idea from @MarcoPolo about using the wasm-ext Transport with js-libp2p/webrtc imports in order to provide WebRTC through browser WebAssembly

Notes & open questions

I'm really not sure how well this will work, but worth a try to binding to the JS WebRTC browser code that is already working to the Rust library.

• Currently I am stuck on how to implement StreamMuxer for the Connection and need some insight and direction from those who know it well.
• Are the Transports going to be separated like they are in js-libp2p, for private and direct? I am assuming yes
• This is a starting point for feedback, input and ideas from others to collab -- it is by no means ready (hence the draft status)

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• A changelog entry has been made in the appropriate crates

[DougAnderson444]

Currently stuck on impl libp2p_core::StreamMuxer for Connection and could use input on how to make it work (poll_inbound/outbound`):

https://github.com/DougAnderson444/rust-libp2p/blob/d9e6f155102a839df7638be7d11632403b777c67/transports/wasm-ext/src/lib.rs#L677

[thomaseizinger]

Even though the scope is a bit bigger, I think you'll be better off binding directly to the browser APIs using web-sys instead of pulling in all of js-libp2p.

I am worried that using js-libp2p in between creates way too many layers that are quite hard to debug.

We already have a webtransport impl that uses web-sys, I'd imagine that that would be quite a good starting point to do something similar for WebRTC! :)

[thomaseizinger]

We consider wasm-ext to be deprecated and would like to move away from it for WebSockets as well but so far that isn't quite ready: #4102.

[DougAnderson444]

Even though the scope is a bit bigger, I think you'll be better off binding directly to the browser APIs using web-sys instead of pulling in all of js-libp2p.

I had a feeling you were going to say that... but you are right, it's worth the extra effort in the long run.

We already have a webtransport impl that uses web-sys, I'd imagine that that would be quite a good starting point to do something similar for WebRTC! :)

I did see that indeed, I'll have a look and see if I've got the bandwidth to take a crack at it.

Are draft Pull Requests from a fork the preferred way to do these sorts of "build in public" work?

[thomaseizinger]

We already have a webtransport impl that uses web-sys, I'd imagine that that would be quite a good starting point to do something similar for WebRTC! :)

I did see that indeed, I'll have a look and see if I've got the bandwidth to take a crack at it.

Are draft Pull Requests from a fork the preferred way to do these sorts of "build in public" work?

💯!

Much appreciated, thank you! :)

The API is the same as what js-libp2p interacts with so you should also be able to get some inspiration from there!

[DougAnderson444]

Opened a WIP draft PR #4248 working towards web_sys bindings instead