padrino && websockets

Question

i'm looking for a way to open and use websockets from within a Padrino application. i know Padrino works with a single thread but i'm looking for a way to open websockets and share variables between its "onopen" "onclose" "onmessage" methods and Padrino controllers.

any idea how it's done ?

links i looked into:

Examples of Eventmachine usage with Padrino and Sinatra (only Sinatra worked for me) em-websocket on GitHub

UPDATE 1: this is my main.rb:

    require 'rubygems'      # <-- Added this require
require 'em-websocket'
require 'padrino-core'
require 'thin'

require File.expand_path("../config/boot.rb", __FILE__)

SOCKETS = []
EventMachine.run do     # <-- Changed EM to EventMachine
#  class App < Sinatra::Base
#      get '/' do
#          SOCKETS.each {|s| s.send "fooooo"}
#          return "foo"
#      end
#  end

  EventMachine::WebSocket.start(:host => '0.0.0.0', :port => 8080) do |ws| # <-- Added |ws|
      # Websocket code here
      ws.onopen {
          ws.send "connected!!!!"
          SOCKETS << ws
      }

      ws.onmessage { |msg|
          puts "got message #{msg}"
          ws.send "ECHO: #{msg}"
      }

      ws.onclose   {
          ws.send "WebSocket closed"
          SOCKETS.delete ws
      }

  end

  # You could also use Rainbows! instead of Thin.
  # Any EM based Rack handler should do.
  #App.run!({:port => 3000})    # <-- Changed this line from Thin.start to App.run!
  Thin::Server.start Padrino.application, '0.0.0.0', 3000

end

i'm getting this exception:

/home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/thin-1.2.11/lib/thin/daemonizing.rb:2:in `require': no such file to load -- daemons (LoadError)
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/thin-1.2.11/lib/thin/daemonizing.rb:2:in `<top (required)>'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/thin-1.2.11/lib/thin/server.rb:50:in `<class:Server>'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/thin-1.2.11/lib/thin/server.rb:48:in `<module:Thin>'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/thin-1.2.11/lib/thin/server.rb:1:in `<top (required)>'
    from main.rb:39:in `block in <main>'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `call'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run_machine'
    from /home/cstore/.rvm/gems/ruby-1.9.2-p290@runtime/gems/eventmachine-0.12.10/lib/eventmachine.rb:256:in `run'
    from main.rb:9:in `<main>'

UPDATE 2: Resolved thanks to Nathan ! I just added 'daemons' to Gemfile and reloaded my application.

Answer 1

Maybe you need to install daemons:

Edit your Gemfile:

# Adding this
gem 'daemons'

Install missing gems:

$ bundle install

Answer 2

What in particular from this example: https://github.com/igrigorik/em-websocket and Any success with Sinatra working together with EventMachine WebSockets? didn't work with Padrino but did with Sinatra? Can you explain the errors you got and why those examples failed (stacktraces)? Maybe we can help investigate.