NodeJS TCP ping example (Typescript)

The following Typescript example allows you to “ping” an IP address or host name not using ICMP but using TCP connection to a given port. If the TCP connection is accepted, the ping is resolved as true. If no connection can be established, it is returned as false. In any case, no data is exchanged and the connection is closed immediately after establishing it.

import { Socket } from "net";

/**
 * Basic TCP ping that returns true if the connection is successful, false if it fails
 * The socket is closed after the connection attempt, no data is exchanged.
 */
export function TCPConnectPing(ipAddress, timeout=5000, port=80): Promise<boolean> {
    return new Promise((resolve) => {
      const socket = new Socket();
      let connected = false;
  
      // Set a timeout for the connection attempt
      const timer = setTimeout(() => {
        if (!connected) {
          socket.destroy();
          resolve(false); // Connection timed out
        }
      }, timeout);
  
      socket.connect(port, ipAddress, () => {
        clearTimeout(timer);
        connected = true;
        socket.destroy();
        resolve(true); // Connection successful
      });
  
      socket.on('error', (error) => {
        clearTimeout(timer);
        if (!connected) {
          resolve(false); // Connection failed due to error
        }
      });
    });
  }