feat(ws): Add compio-ws: Async WebSocket support for compio runtime

[krishvishal]

This PR adds compio-ws, a WebSocket library that brings async WebSocket support to the compio runtime. It integrates the tungstenite WebSocket protocol implementation with compio. The structure of this project is mainly based on tokio-tungstenite.

Features

• Client & Server APIs - Functions for both accepting connections and initiating client connections
• Full WebSocket Protocol Support - Built on tungstenite for spec-compliant WebSocket handling
• Optional TLS Support - Secure WebSocket connections via rustls.
• Added GrowableSyncStream - a SyncStream like structure but with growable internal read/write buffers.
• Autobahn Test Suite - Scripts and configurations for protocol compliance testing

Feature flags

• connect - Enables client connection functionality (requires compio-net)
• rustls - TLS support via rustls
• rustls-native-certs - Use system native certificates
• webpki-roots - Use Mozilla's CA roots

Examples

• echo_server / echo_server_tls - Simple echo servers
• client / client_tls - Client examples
• autobahn-client / autobahn-server - Autobahn test suite integration

---

You can test server and client using the following from the compio root dir:

Run cargo run -p compio-ws --example echo_server --features connect to spin up a WS server and in a separate terminal run cargo run -p compio-ws --example client --features connect

[Copilot]

Pull Request Overview

This PR adds WebSocket support to the compio runtime by introducing a new compio-ws crate. It provides async WebSocket functionality built on top of the tungstenite library, with optional TLS support via rustls.

Key Changes:

• New compio-ws crate with client/server WebSocket support
• Growable sync stream adapter for bridging async/sync I/O
• TLS integration with optional certificate loading features
• Examples demonstrating usage and Autobahn test suite integration

Reviewed Changes

Copilot reviewed 17 out of 18 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
compio-ws/src/lib.rs	Core WebSocket stream implementation and handshake functions
compio-ws/src/growable_sync_stream.rs	Buffered stream adapter with dynamic growth
compio-ws/src/stream.rs	MaybeTlsStream enum for plain/TLS abstraction
compio-ws/src/rustls.rs	TLS client support with certificate loading
compio-ws/Cargo.toml	Package configuration with feature flags
compio-ws/examples/*	Example servers and clients
compio-ws/scripts/*	Autobahn test automation scripts
Cargo.toml	Workspace configuration update

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[Berrysoft]

You might want to pass the CI first:)

[krishvishal]

@Berrysoft I've fixed fmt and clippy issues.

I've overlooked that the project uses nightly.

Please run the CI again.

[Berrysoft]

It would be better if there are some tests.

[krishvishal]

@Berrysoft I've added some tests that test basic websocket functionality and addressed the review comments. Please review when you can.

[Berrysoft]

Thank you very much! There are some more comments:

• Would you want to replace the SyncStream in compio-io directly? Well it's OK to keep the current one, and I'll do that if you don't want to spend more time.
• I hesitated whether to make compio-ws as a separate project, but now it seems that it's not a large codebase, so it's OK. It is necessary to also add compio-ws as the dependency of compio crate, and to add an alias ws, too. The important features of compio-ws should be reflected in the features of compio, so that users won't need to write another individual dependency.
  • Note that although you have added the tests, they didn't run because they need new features. You may add the features to the all feature in compio.
• @George-Miao is a bit busy now. He commented that tungstenite is a little inefficient because there's a buffer inside, and now we need to add another buffer for the gap between sync code and async code. If you have some other ideas about that, feel free to discuss about it.

[krishvishal]

@Berrysoft

1. I'm short on time. I won't able to work on replacing SyncStream.
2. I've addressed this in the recent commit.
3. I think we have to implement a compio specific websocket protocol implementation that can work with owned buffers. Can be considered as a future performance optimization work. Tungstenite is the defacto standard in rust ecosystem but its not the fastest one.

Please review when you can.

[Berrysoft]

Thanks, @krishvishal ! But it seems that you haven't pushed the recent changes...

[krishvishal]

@Berrysoft oops, sorry. I've pushed now. Please check.

[Berrysoft]

LGTM. Here's a plan that I'll do next:

• Move GrowableSyncStream to compio-io.
• Cleanup the features of compio, maybe?
• Think about whether to make MaybeTlsStream public. It'll be useful for cyper.

Don't worry about the lint CI. I'll squash the commits.

[AsakuraMizu]

Has anyone missed it?

[Berrysoft]

Oh, it should be removed.

[Berrysoft]

Addressed in #508