source: trip-planner-front/node_modules/socks/docs/examples/javascript/bindExample.md@ bdd6491

# socks examples

## Example for SOCKS 'bind' command

The bind command tells the SOCKS proxy server to bind and listen on a new TCP port for an incoming connection. It communicates the newly opened port back to the origin client. Once a incoming connection is accepted by the SOCKS proxy server it then communicates the remote host that connected to the SOCKS proxy back through the same initial connection via the origin client.

This can be used for things such as FTP clients which require incoming TCP connections, etc.

**Connection Steps**

1. Client -(bind)-> Proxy    (Tells the proxy to bind to a new port)
2. Client <-(port)- Proxy    (Tells the origin client which port it opened)
3. Client2 --> Proxy    (Other client connects to the proxy on this port)
4. Client <--(client2's host info)  (Proxy tells the origin client who connected to it)
5. Original connection to the proxy is now a full TCP stream between client (you) and client2.
6. Client <--> Proxy <--> Client2


## Usage

The 'bind' command can only be used by creating a new SocksClient instance and listening for 'bound' and 'established' events.


```typescript
const SocksClient = require('socks').SocksClient;

const options = {
  proxy: {
    host: '104.131.124.203',
    port: 1081,
    type: 5
  },

  // This should be the ip and port of the expected client that will connect to the SOCKS proxy server on the newly bound port.
  // Most SOCKS servers accept 0.0.0.0 as a wildcard address to accept any client.
  destination: {
    host: '0.0.0.0',
    port: 0
  },

  command: 'bind'
};

const client = new SocksClient(options);

// This event is fired when the SOCKS server has started listening on a new port for incoming connections.
client.on('bound', (info) => {
  console.log(info);
  /*
  {
    socket: <Socket ...>,
    remoteHost: { // This is the remote ip and port of the SOCKS proxy that is now accepting incoming connections.
      host: '104.131.124.203',
      port: 49928
    }
  }
  */
});

// This event is fired when the SOCKS server has accepted an incoming connection on the newly bound port.
client.on('established', (info) => {
  console.log(info);
  /*
  {
    socket: <Socket ...>,
    remoteHost: { // This is the remote ip and port that connected to the SOCKS proxy on the newly bound port.
      host: '1.2.3.4',
      port: 58232
    }
  }
  */

  // At this point info.socket is a regular net.Socket TCP connection between client and client2 (1.2.3.4) (the client which connected to the proxy on the newly bound port.)

  console.log(info.socket);
  // <Socket ...>  (this is a raw net.Socket that is established to the destination host through the given proxy servers)
});

// SOCKS proxy failed to bind.
client.on('error', () => {
  // Handle errors
});
```