open serialport and log data automatically under various events - node.js

Question

I am using a COM3 port and iam using the serialport module to read from the serialport. What I want is an automatic logging system which logs the data from serialport under the following events.
1.close program and reopening the program
2.restart my pc
3.unplug the usb cable and plug it again
4.restart the Arduino device
I want to open the serialport and log data received from it automatically whenever the above events occur. How to handle these cases.
Currently, this is the code iam using
var fs = require('fs');
const SerialPort = require('serialport')
const Readline = require('#serialport/parser-readline')
const port = new SerialPort('COM3')
const parser = new Readline()
port.pipe(parser)
parser.on('data', function (data) {
const index = data.indexOf('*#SENSOR_DATA')
if(index != -1){
fs.appendFileSync("sensor_data.txt", new Date(), 'utf8')
fs.appendFileSync("sensor_data.txt", data, 'utf8')
}
})
port.on('error', function(err) {
fs.appendFileSync("sensor_data.txt", new Date(), 'utf8')
fs.appendFileSync("sensor_data.txt", err, 'utf8')
console.log(err);
})
port.write('ROBOT PLEASE RESPOND\n')
How can I handle the above mentioned cases?

Answer 1

close program and reopening the program
Logging the data from the port on starting of the program, should be straight forward, i.e. the running of your script.
Closing of the program, depends on what you scenarios you want to handle, graceful or non graceful exits of the program. To implement this you can add event listeners on the nodeJS process object. You can register event handlers for when the process is going to exit to do some action.
process.on('SIGINT', () => {
// read my data from Serial
process.exit(-1);
})
restart my pc
Depending on what your OS is, you could configure your nodejs process as a service, or you could run it via cron. For example cron (depending on the OS) has the option for scheduling jobs on reboot. Regardless of your OS, you will be able to schedule jobs or create a service to ensure your process starts when your machine restarts.
unplug the usb cable and plug it again &
restart the Arduino device
For this I would look at the different parsers that are available for serialport. For example the ReadyParser.