在不同的模块（Node.js）中使用 Socket.io 发射

Question

I've been struggling to get this working for a day now, I'm hoping someone can help with some foundation for me as I've tried to read up on this with little success.

Purpose of app: My app takes a username and password from a user, launches a module that runs puppeteer to automate tasks while providing the user with live updates on the puppeteer progress.

2 users connected at the same time can enter different credentials and puppeteer should run simultaneously outputting progress to that specific user of their job.

I'm using node.js + express + ejs + socket.io created with the express generator.

The file structure looks like this:

bin/
--www.js
app.js
scraper.js
views/
--index.js
routes/
--index.ejs
public/
  ...

I've got socket.io working in the www.js module where the server is configured, what I've set up is where a user clicks the submit button on the front end, socket.io emits a unique message received (in www.js) and calls the function launchScraper inside scraper.js .

I want launchScraper to then emit the live updates to that individual user. ie logged in successfully, job done etc.

Question: I cannot seem to get scraper.js to emit the message to that unique user (using their socket.id ), I think I'm missing some theory. Here's my code:

www.js

const scraper = require('../scraper');
const socketio = require('socket.io');
...
const server = http.createServer(app);
const io = socketio(server);
...
io.on('connection', (socket) => {
console.log('New connection: '+ socket.id);
...
  socket.on('launchScraper', (socket) =>{
  console.log('received client launchScraper');
  scraper.launchScraper(io,userCredentials);
  })

scraper.js

 const puppeteer = require('puppeteer'); 

//This emits the message to all users, but I've tried variations sending `socket.id` in etc and I cannot seem to get it to work.
function emitMessage(io,msg){
io.emit('message',msg);
console.log(msg);
}

async function launchScraper(io,userData) {

emitMessage(io, 'Launching Scraper...'); //Sending io in
const browser = await puppeteer.launch({..});
const page = await browser.newPage();
...

Can anyone help or suggest a better way to do this? I just don't want a lot of code is the www.js as I don't believe the code should live there..

I'm a newbie on Node and I'm struggling to understand instances, constructors etc.

Answer 1

Turns out I needed to send the "socket" with my request and not the "io" instance.

Doing that seemed to resolve it.