Cheery - Minimal Relay Server

A high-performance relay server designed to facilitate peer-to-peer connections between clients using a simple binary protocol.

Features

• 🚀 Ultra-fast C implementation using epoll
• 🔄 Simple binary protocol
• ⏱️ Automatic connection timeouts
• 🔒 No external dependencies
• 💻 Cross-platform (Linux/Unix)

Build & Run

1. Clone the repository:

   git clone https://github.com/yourusername/cheery.git
   cd cheery

2. Build the server:

   make

3. Run the server:

   ./build/main

The server will listen on 0.0.0.0:8765 by default.

Binary Protocol

Packet Structure

All packets start with a 1-byte command followed by optional payload.

Commands

0x01 - Create Room

Create a new room with a 4-byte room code.

[0x01][code:4]

0x02 - Join Room

Join an existing room with a 4-byte room code.

[0x02][code:4]

Responses:

• 0x04 - Matched with peer
• 0x05 - Waiting for peer

0x03 - Relay Data

Send data to the paired peer.

[0x03][data...]

Get User IP

{
    "type": "get_ip",
    "target": "username_to_query"
}

Server Responses

• User List Update (sent to all clients when user list changes):

  {
      "type": "user_list",
      "users": ["user1", "user2"]
  }

• IP Response (response to get_ip request):

  {
      "type": "ip_response",
      "target": "queried_username",
      "ip": "192.168.1.100"
  }

  or if user is not found:

  {
      "type": "ip_response",
      "target": "nonexistent_user",
      "error": "User offline"
  }

Project Structure

• main.py - Main server implementation
• pyproject.toml - Project configuration and dependencies
• poetry.lock - Lock file for reproducible builds

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.