ZeroMQ + Node.js Messaging Queue

consumer.js

var os = require('os');
var cluster = require('cluster');
var zmq = require('zmq');

if(cluster.isMaster) {
    var cpuCount = os.cpus().length;
    for(var i = 0; i < cpuCount; i++) cluster.fork();
} else {
  var socket = zmq.socket('pull')
  socket.identity = 'consumer' + process.pid;

  socket.on('message', function(msg) {
      console.log(socket.identity + ' received: ' + msg.toString());
  });

  socket.connect('tcp://0.0.0.0:9999');
  console.log(socket.identity + 'connected on 9999');
}

device.js

var zmq = require('zmq');
var inflow = zmq.socket('pull');
var outflow = zmq.socket('push');

inflow.bind('tcp://0.0.0.0:9998', function(err) {
  if(err) throw err;
  console.log('inflow listening on 9998');

  inflow.on('message', function(msg){
    console.log('relaying: ' + msg);
    outflow.send(msg);
  });
});

outflow.bind('tcp://0.0.0.0:9999', function(err) {
  if(err) throw err;
  console.log('outflow listening on 9999');
});

producer.js

var zmq = require('zmq');
var socket = zmq.socket('push');
var counter = 0;

socket.connect('tcp://0.0.0.0:9998'); // connect to device.inflow
console.log('producer connected on 9998');

setInterval(function(){
    console.log('sending %d', counter++);
    socket.send(counter);
}, 100);