nodejs send data to arduino

serialtest.js

const SerialPort = require('serialport');
const port = new SerialPort('/dev/cu.usbmodem****', {
  parser: SerialPort.parsers.readline('\n'),
  baudrate: 9600
})

port.on('open', function () {
  console.log('Serial open.');
})

port.on('data', function (data) {
  console.log('Data: ' + data)
  // send rgb data
  write(data)
})

function write(data) {
    console.log('Write: ' + data);
    port.write(new Buffer(data), function(err, results) {
      if(err) {
        console.log('Err: ' + err)
        console.log('Results: ' + results)
      }
  })
}