ws-serial-gateway

A tiny WebSocket‑to‑Serial‑Port gateway written in Rust.

• A client connects to ws://<host>:<port>/<endpoint>
• The gateway opens the serial device configured for <endpoint> and forwards all data both ways.

Features

Feature	Description
Cross‑platform	Works on Windows, Linux and macOS
Simple configuration	YAML file mapping endpoint names to serial ports and baud rates
MIT licensed	Free to use, modify and distribute

Safety and Security

Do not expose this service to untrusted networks.

I am not interested in adding TLS to this software directly. Serve this behind a reverse proxy (e.g. nginx) that can handle TLS termination, access control, etc.

Scalability

Each serial port is still a serial port. That means it's inherently a single- user device, and you can only have one client connected to it at a time. If another program on your server is accessing the same serial port, do not expect to be able to connect via this server at the same time.

Getting started

Prerequisites

• Rust toolchain (stable) – install via https://rustup.rs
• A serial device (e.g. Arduino, USB‑UART, etc.)

Clone the repository

You know what to do.

Configuration

Edit config.yaml in the project root to configure your server endpoint and serial devices.

Build and run

cargo run --release

The server will listen on the configured IP and port.
Open a WebSocket client to ws://<host>:<port>/mydevice (replace mydevice with an endpoint you defined).

Example client (Node.js)

const WebSocket = require('ws');
const ws = new WebSocket('ws://127.0.0.1:4400/mydevice');

ws.binaryType = 'arraybuffer';

ws.on('open', () => {
  console.log('WebSocket opened');
  // Send a command to the serial device
  ws.send(Buffer.from('AT\r\n'));
});

ws.on('message', data => {
  console.log('From serial:', Buffer.from(data).toString());
});

Stopping the server

Press Ctrl‑C in the terminal where cargo run is executing or send SIGINT to the process.

License

This software is licensed under the MIT License – see the LICENSE file for details.