'use strict'; const http = require('http'); const cluster = require('cluster'); function handleRequest(request, response) { response.end('hello world\n'); } const NUMBER_OF_WORKERS = 2; var workersOnline = 0; if (cluster.isMaster) { cluster.on('online', function() { if (++workersOnline === NUMBER_OF_WORKERS) { console.error('all workers are running'); } }); process.on('message', function(msg) { if (msg.type === 'getpids') { const pids = []; pids.push(process.pid); for (var key in cluster.workers) pids.push(cluster.workers[key].process.pid); process.send({ type: 'pids', pids: pids }); } }); for (var i = 0; i < NUMBER_OF_WORKERS; i++) { cluster.fork(); } } else { const server = http.createServer(handleRequest); server.listen(0); }