EM-based pubsub

gistfile1.rb

require 'eventmachine'
require 'awesome_print'

class Channel
  def initialize
    @sockets = []
  end

  def subscribe(socket)
    @sockets << socket
  end

  def publish(message)
    @sockets.each { |socket| socket.send_data(message) }
  end

  def unsubscribe(socket)
    @sockets.delete(socket)
  end
end

$channel = Channel.new

module PubSub
  def post_init
    puts 'connection established'
    $channel.subscribe(self)
  end

  def receive_data(data)
    puts "received data: #{data.ai}"
    $channel.publish(data)
  end

  def unbind
    puts 'connection closed'
    $channel.unsubscribe(self)
  end
end

EM.run do
  EM.start_server('0.0.0.0', 8081, PubSub)

  Signal.trap('INT')  { EM.stop }
  Signal.trap('TERM') { EM.stop }
end