WebSocket

[ronag]

https://fetch.spec.whatwg.org/#websocket-protocol

[mcollina]

cc @lpinca

[szmarczak]

This should be quite easy. Reference: https://github.com/szmarczak/http2-wrapper/blob/master/examples/ws/index.js

[lpinca]

@szmarczak I know it is a demo but that example basically skips the opening handshake. There is no validation and no subprotocol/extension negotiation.

[WenheLI]

Interested in this one. Would try to implement if it is availabe!

[joshxyzhimself]

Are there any advantages in building websockets here on top of undici compared to what exists in https://github.com/websockets/ws? (maybe performance?)

[mcollina]

I'm totally ok in using ws for this. It's a great module by @lpinca and I hope we will emebed it in core one day.

[jodevsa]

@mcollina this would be really a great opportunity for me to learn more about WS. Can I start working on this?

[mcollina]

I don't think we should do another implementation, I think the ws module is great, we might just pull it in as a dep.

cc @lpinca @KhafraDev

[KhafraDev]

ws is great but I think the implementation is too different from the spec WebSocket. There's also outstanding issues where it uses a custom EventTarget (websockets/ws#1818). Then there's a bunch of webidl issues I could spot with a cursory glance (Websocket extends EventEmitter, underscore indexed properties) and the fact that WPTs aren't being run.

Undici (or maybe the nodejs org) should fork or add ws as a git submodule where we could make breaking changes from the ws api & run WPTs, to ensure cross compatibility.

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Basically I see this as another spec fetch vs. node-fetch issue. Both might share a similar API but are different enough that there isn't a cross-compatibility guarantee.

[lpinca]

Following the https://websockets.spec.whatwg.org/ spec in every single detail is a non-goal for ws. It is limiting and there is no real advantage in my opinion.

I think jsdom runs the websockets web-platform-tests. They use ws under the hood with some minor adjustments.

[mcollina]

I think we should have our own implementation then. Maybe reusing ws or some parts of it under the hood.