Using node.js to recognize when Arduino Micro is plugged into USB - node.js

Question

First off, I'm new to both node.js and the concept of async functions and would greatly appreciate any help I can get here.
I've been trying to write a script using the node.js serialport module to scan the ports on my Windows machine and do simple stuff once an Arduino Micro is connected to a port. The below works fine if the Arduino is already connected, but I can't work out how to extend it so that it will wait, indefinitely, until the Micro is plugged in. It just terminates if nothing is found.
const serialPort = require('serialport');
var portName;
serialPort.list().then(function(ports){
ports.forEach(function(portInfo){
if (portInfo.vendorId == 2341 && portInfo.productId == 8037) {
portName = portInfo.path;
var myPort = new serialPort(portName);
myPort.on('open' , function() {
showPortOpen();
myPort.write('RL'); // command to initiate functions in Arduino code
});
myPort.on('data' , readSerialData); // echo data from Arduino
myPort.on('close', showPortClose);
}
})
});
function readSerialData(data) {
console.log(data);
}
function showPortOpen() {
console.log(portName,'opened');
}
function showPortClose() {
console.log(portName,'closed');
}

Answer 1

Problem solved in double-quick time. Thank you :-)
Not sure if it's the cleanest approach but by re-calling the setInterval function when the port closes, I have a script that waits and finds the Arduino once it's plugged into the USB and, if subsequently unplugged, will find it again once it's plugged in again. Just what I want!
const serialPort = require('serialport');
var portName;
loop(); // start searching for Arduino on a port
function loop() {
loopId = setInterval(function() {
serialPort.list().then(function(ports){
ports.forEach(function(portInfo){
if (portInfo.vendorId == 2341 && portInfo.productId == 8037) {
portName = portInfo.path;
var myPort = new serialPort(portName);
myPort.on('open' , function() {
showPortOpen();
myPort.write('RL'); // command to initiate Arduino functions
});
myPort.on('data' , readSerialData); // echo data from Arduino
myPort.on('close', showPortClose);
}
})
})
}, 1000)
};
function readSerialData(data) {
console.log(data);
}
function showPortOpen() {
console.log(portName,'opened');
clearInterval(loopId); // stop looping once Arduino found on port
}
function showPortClose() {
console.log(portName,'closed');
loop(); // start over when Arduino port is closed
}