NodeJS Clusters

nodejs_clusters.js

'use strict';

const cluster = require('cluster');
const http = require('http');
const numCores = 3;

var workerIds = [];

if (cluster.isMaster) {
  console.log(`Master ${process.pid} is running`);

  // Fork workers.
  for (let i = 0; i < numCores; i++) {
    cluster.fork();
  }

  // add workers to array
  for (const id in cluster.workers) {
    workerIds.push(cluster.workers[id].id)
  }

  cluster.on('exit', (worker, code, signal) => {
    console.log(`worker ${worker.process.pid} died`);
  });
} else {
  
  var worker = cluster.worker.id;

  if(worker == 1){ // start server
  	console.log("I'll start server");
    http.createServer((req, res) => {
      res.writeHead(200);
      res.end('hello world\n');
    }).listen(8000);
  }

  if(worker == 2){ // run bull
  	console.log("I'll run bull");
  }

  if(worker == 3){ // run a third party server
  	console.log("Some random stuff...");
  }

  console.log(`Worker ${process.pid} started`);
}