favourable.rb

class PreferedImplementation < Ruote::ProcessObserver
  def on_launch(wfid, workitem, variables)  # stash and pdef could also be there
    $stderr.puts "Hey! #{wfid} started with #{workitem.fields}"
  end

  def on_end(wfid, workitem)
    $stderr.puts "#{wfid} finaly made it! (the workitem ended up as #{workitem.fields})"
  end

  def on_flunk(wfid, workitem, error)
    $stderr.puts "Hey, #{wfid} flunked with #{error.class.name}: #{error.message} - looking like #{workitem.fields}"
  end

  def on_cancel(wfid, workitem)
    $stderr.puts "To bad... #{wfid} got canceled"
  end

  def on_step(wfid, workitem)
    $stderr.puts "I'm just a simplified version of on_msg called when the participant changes ;)"
  end
end

observer.rb

module Ruote
  # take on_msg and translate it into more detailed actions
  class ProcessObserver
    attr_accessor :context, :options

    def initialize(context, options)
      @context = context; @option = options
    end

    def on_msg(msg)
      case msg['action']
      when 'launch'
        on_laucnh(msg)
      # ... etc ...
      end
    end

    def on_launch(msg)
    end

    def on_end(msg)   # or on_terminate
    end
   
    def on_flunk(msg)
    end

    def on_cancel(msg)
    end

    def on_step(msg)
    end
  end
end