ZeroMQ + Node.js + Socket.io + UI for sending message from Ruby to a Javascript UI running on Node.js

Readme.md

Install the following requirements:

brew info zeromq
npm install zmq
npm install socket.io
gem install ffi-rzmq

Within the app directory run the following commands in different panes.

ruby worker.rb
node app.js
ruby ventilator.rb

app.js

var app = require('http').createServer(handler), 
    io = require('socket.io').listen(app),
    fs = require('fs'),
    zmq  = require('zmq'), 
    receiver = zmq.socket('pull');

app.listen(8080);

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }
 
    res.writeHead(200);
    res.end(data);
  });
}

io.configure( function(){
  io.set('log level', 3);
  io.set('transports', [ 'websocket', ]);
});

io.sockets.on('connection', function (socket) {
  receiver.on('message', function(message) {
    socket.emit('marker', { 'message': escape(message) });
  });
});
 
receiver.bindSync("tcp://*:5558");

index.html

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script type="text/javascript" src="node_modules/socket.io/node_modules/socket.io-client/dist/socket.io.js"></script>

<script>
  var socket = io.connect('http://localhost:8080');

  socket.on('marker', function (data) {
    console.log(data.message);
  });
</script>

ventilator.rb

require 'rubygems'
require 'ffi-rzmq'

context = ZMQ::Context.new(1)

# Socket to send messages on
sender = context.socket(ZMQ::PUSH)
sender.bind("tcp://*:5557")

# The first message is "0" and signals start of batch
sender.send_string('0')

# Send 50 tasks
50.times do |workload|
  $stdout << "#{workload}."

  sender.send_string(workload.to_s)
  sleep(0.2)
end

Kernel.sleep(1)  # Give 0MQ time to deliver

worker.rb

require 'rubygems'
require 'ffi-rzmq'

context = ZMQ::Context.new(1)

# Socket to receive messages on
receiver = context.socket(ZMQ::PULL)
receiver.connect("tcp://localhost:5557")

# Socket to send messages to
sender = context.socket(ZMQ::PUSH)
sender.connect("tcp://localhost:5558")

# Process tasks forever
while true
  receiver.recv_string(msec = '')
  $stdout << "#{msec}."
  sender.send_string(msec)
end