Node.js - get reference to processes spawned by child_process.spawn

Question

Is it possible to somehow find a reference to child processes spawned by current process in node.js? I have some code that uses a third party library that spawns a new process. I would like to find a reference to this process and attach some events to it and react to output.

I want to do something like this.

thirdparty.js

const cp = require('child_process');

function spawn(executable, args, stdio) {
  cp.spawn(executable, args, stdio);
}

module.exports = spawn

main.js

const spawn = require('thirdparty');

spawn()
const child = findTheProcess()
child.stdout.on('data', data => {
  // do stuff
});


child.on('message', data => {
  // do stuff

});

One idea that I had was to override cp.spawn but that sounds horrible.

Answer 1

If you return newly created process in thirdpaty.js you'll be able to reference it in main.js

Modified code to list current directory:

thirdparty.js

const cp = require('child_process');

function spawn(executable, args, stdio) {
  return cp.spawn(executable, args, stdio);
}

module.exports = spawn

main.js

const spawn = require("./thirdparty")

const child = spawn("ls")

child.stdout.on("data", (data) => {
  console.log(data.toString())
})

child.on("message", (data) => {
  console.log(data.toString())
})