Tunnel Client (CLI)

The tunnel-client is a Node.js CLI tool that exposes your local server to the internet.

How it Works

1. Connection: The CLI connects to the Tunnel Server via a WebSocket (wss://tunnel.mohammadrasel.com).
2. Registration: It sends a register event to claim a subdomain (e.g., myapp).
3. Listening: It keeps the WebSocket open, waiting for requests.
4. Forwarding:
   • When the Tunnel Server receives a public HTTP request (e.g., https://myapp.tunnel.mohammadrasel.com), it serializes the request and sends it to the CLI over the WebSocket.
   • The CLI receives this message.
   • The CLI uses axios to make the actual HTTP request to your local service (e.g., http://localhost:3000).
   • The CLI captures the response (status, headers, body).
   • The CLI sends the response back to the Tunnel Server over the WebSocket.
5. Response: The Tunnel Server deserializes the response and sends it to the original public user.

Usage

# Start a tunnel forwarding to localhost:3000
dt start --port 3000 --subdomain myapp --server wss://tunnel.mohammadrasel.com

# Options
--port, -p      Local port to expose (default: 3000)
--subdomain, -s Requested subdomain (default: random)
--server        Tunnel server URL (default: ws://localhost:8000)

Architecture Diagram

sequenceDiagram
    participant PublicUser
    participant TunnelServer
    participant CLI
    participant LocalApp

    CLI->>TunnelServer: WebSocket Connect (Register 'myapp')
    TunnelServer-->>CLI: Registered 'myapp.devtunnel.net'

    PublicUser->>TunnelServer: HTTP GET https://myapp.devtunnel.net/api/users
    TunnelServer->>CLI: WS Message (type: request, path: /api/users)
    CLI->>LocalApp: HTTP GET http://localhost:3000/api/users
    LocalApp-->>CLI: JSON Response { "users": [] }
    CLI->>TunnelServer: WS Message (type: response, body: {...})
    TunnelServer-->>PublicUser: HTTP 200 OK { "users": [] }