Set webpack dev server to use next avail open port in a range

webpack.config.js

const net = require('net');

const getOpenPort = async (port, maxPort) => {
  const isPortAvail = (currentPort) => new Promise((resolve, reject) => {
    const tester = net.createServer()
      .once('error', (err) => (err.code === 'EADDRINUSE' ? resolve(false) : reject(err)))
      .once('listening', () => tester.once('close', () => resolve(true)).close())
      .listen(currentPort);
  });
  
  /* eslint-disable-next-line */
  console.log(`Trying port ${port}`);
  
  if (await isPortAvail(port)) {
    return port;
  }
  if (port < maxPort) {
    return getOpenPort(port + 1, maxPort);
  }
  return new Error('no avail port');
};

// truncated config
module.exports = {
  devServer: {
    port: await getOpenPort(51256, 51259)
  }
}