Check Port Availability

portAvailable.js

import net from "net";

export default (port) =>
  new Promise((resolve) => {
    const remove = (client) => {
      client.removeAllListeners("connect");
      client.removeAllListeners("error");
      client.end();
      client.destroy();
      client.unref();
    };
    const client = new net.Socket();
    client.once("connect", () => {
      resolve(false);
      remove(client);
    });
    client.once("error", (err) => {
      if (err.code === "ECONNREFUSED") resolve(false);
      else resolve(true);
      remove(client);
    });
    client.connect(port, () => {});
  });