rails asset pipeline - auto invoke javascript based on controller / action

_javascript_object_invoke.html.erb

<!-- 
1) include in layout files after all other javascript includes
2) if you have coffeescript classes that match your controller name - they will be invoked automatically


WARNING: as a general rule don't write js like this with ruby mixed in, 
         this is one of those rare cases where it 'works' well
-->
<script>
  $(document).ready(function () {
    var o;
    if (window.APP) {
      if (window.APP.<%= controller_name.classify %>) {
        o = new window.APP.<%= controller_name.classify %>();
        if (o.<%= action_name %>) {
          o.<%= action_name %>();
        } else {
          log("NO: window.APP.<%= controller_name.classify %>.<%= action_name %>");
        }
      } else {
        log("NO: window.APP.<%= controller_name.classify %>");
      }      
    }
    else {
      log("NO: window.APP");
    }
  });
</script>

users.js.coffee

# CoffeeScript class maps to controller, methods map to actions
class User
  
  new: ->
    @bindForNewUserForm()

  create: -> 
    @bindForNewUserForm() # incase of server side validation rendering new view in create action

  profile: ->
    # call other re-usable js 'component'
    new window.APP.Users.Profile().run()

# bind objects to APP namespace
window.APP ?= {}
window.APP.User = User