Broadcast Server

A small experimental WebSocket broadcast server CLI program written in Rust. The server accepts WebSocket connections and broadcasts text messages received from one client to all other connected clients.

This repository currently contains only the server module. A separate client implementation is planned for later. You can test the server now using a CLI WebSocket client such as wscat.

What this project is

• Language: Rust
• Runtime: smol
• WebSocket library: async-tungstenite
• Purpose: simple broadcast server useful for learning or small demos; accepts connections, relays text messages between clients, and gracefully shuts down on Ctrl+C.

Current status

• Server module implemented and listening on 127.0.0.1:8080 by default.
• Client module: not implemented yet.

Prerequisites

• Rust toolchain (rustup + cargo). Install via https://rustup.rs/
• Node.js/npm (optional) for wscat if you want to use it to test the server.

To install wscat (global):

npm install -g wscat

Build and run

From the repository root:

# build (optional)
cargo build --release

# run in debug (fast compile & run)
cargo run

# or run the release binary
cargo run --release

Testing with wscat

First start the broadcast server with the start command:

cargo run start

Then open two or more terminals and connect to the running server:

wscat -c ws://127.0.0.1:8080

Type a message in one terminal and press Enter — the text should appear in the other connected terminals (the message sender does not receive its own message back).

Example session:

1. Terminal A: wscat -c ws://127.0.0.1:8080
2. Terminal B: wscat -c ws://127.0.0.1:8080
3. In A: hello everyone -> B receives hello everyone

When you press Ctrl+C in the server terminal, the server will attempt a graceful shutdown and notify connected clients with a close frame.

Troubleshooting

• If you see an error that the address is in use, either stop the process using that port or change the bind address/port in src/server/mod.rs.
• If wscat is not connecting, verify the server is running and that you used 127.0.0.1 rather than localhost (the server binds to the loopback address in the current implementation).

Next steps (planned)

• Implement a client module in Rust (WebSocket client library).

Notes for contributors

• The server currently uses smol and channels for brokered broadcasting. The registry limits client id to 0..=255 (u8). Consider increasing the id type if you expect many clients.
• See src/server/mod.rs for the primary server implementation and src/main.rs / src/cli.rs for how the server is started.