websockets.rb

require 'redis'
require 'em-websocket'
require 'sinatra/base'
require 'sinatra'

SOCKETS = []
#@redis = Redis.new(:host => '127.0.0.1', :post => 6379)
@redis = Redis.new



# Creating a thread for the EM event loop
Thread.new do
  EventMachine.run do
    
    class App < Sinatra::Base
      # Sinatra code here
      get '/' do
        erb :index
      end
    end
    
    # Creates a websocket listener
    EventMachine::WebSocket.start(:host => '0.0.0.0', :port => 8080) do |ws|
      ws.onopen do
        # When someone connects I want to add that socket to the SOCKETS array that
        # I instantiated above
        puts 'creating socket'
        SOCKETS << ws
      end
      
      ws.onmessage do |message|
        #@sockets.each {|s| s.send message}
        @redis.publish('ws', message)
      end

      ws.onclose do
        # Upon the close of the connection I remove it from my list of running sockets
        puts 'closing socket'
        SOCKETS.delete ws
      end
    end #EventMachine::WebSocket
    
    App.run!({:port => 3000})
    
  end #EventMachine.run
end #Thread

# Creating a thread for the redis subscribe block
Thread.new do
  @redis.subscribe('ws') do |on|
    # When a message is published to 'ws'
    on.message do |chan, msg|
     puts "sending message: #{msg}"
     # Send out the message on each open socket
     SOCKETS.each {|s| s.send msg} 
    end
  end
end

sleep