Websocket on Rails

Short showcase how to use the awesome websocket technology in a Rails project using websocket-rails

Transcript

1. Websocket on rails Building realtime webapps
3. I'm a Java Developer who likes to ride the rails!
4. The future is now!
5. What's so great about Websocket?
6. HTTP is half-duplex
7. Asynchronous full-duplex communication Websocket is asynchronous & full-duplex
8. So, a little less of this...
9. So instead of this... Or this...
10. Or this...
11. You tell me... what's new?
12. Push
13. So, how to ride the rails with this?
14. Introducing websocket-rails 1. echo "gem 'thin'" >> Gemfile 2. echo "gem 'websocket-rails'" >> Gemfile 3. bundle install 4. rails g websocket_rails:install
16. Ruby eventmachine
18. Map events to controller actions WebsocketRails::EventMap.describe do # You can use this file to map incoming events to controller actions. # One event can be mapped to any number of controller actions. The # actions will be executed in the order they were subscribed. namespace :rsvp do subscribe :new, :to => RsvpController, :with_method => : rsvp end end
19. Use rails-like controllers class RsvpController < WebsocketRails::BaseController def initialize_session # initialize application scoped variables here @rsvp_yes_count = 0 end def rsvp @rsvp_yes_count += 1 if message broadcast_message :new_rsvp, @rsvp_yes_count end end
20. Trigger and bind to events in the client $ -> dispatcher = new WebSocketRails('localhost:3000/websocket') dispatcher.on_open = (data) -> console.log "Connection has been established: #{data}" $('#rsvp_yes').bind 'click', (message) => dispatcher.trigger 'rsvp.new', true dispatcher.bind 'new_rsvp', (rsvp_yes_count) => $('#rsvp_yes_count').html rsvp_yes_count
21. Broadcast to anyone out there, or...
22. ...only push to whom is interested
23. Use complex messages and channels (1) class RsvpController < WebsocketRails::BaseController ... def rsvp @rsvp_yes_count += 1 if message[:attending] rsvp = { :yes => @rsvp_yes_count } WebsocketRails[:rsvp].trigger 'new', rsvp end end
24. Use complex messages and channels (2) $ -> dispatcher = new WebSocketRails('localhost:3000/websocket') $('#rsvp_yes').bind 'click', (message) => rsvp = attending: true dispatcher.trigger 'rsvp.new', rsvp channel = dispatcher.subscribe 'rsvp' channel.bind 'new', (rsvp) => $('#rsvp_yes_count').html rsvp.yes
25. Demo
26. References Websocket spec • http://dev.w3.org/html5/websockets/ Websocket-rails project page • http://danknox.github.com/websocket-rails/ My project • https://github.com/jeroenr/followup Ruby eventmachine • http://rubyeventmachine.com/