ypz.rb

require 'ruote'

ruote = Ruote::Dashboard.new(Ruote::Worker.new(Ruote::HashStorage.new))

class GrabUptime < Ruote::Participant
  def on_workitem
    node = workitem.params['node']
    workitem.fields["uptime_#{node}"] = `ssh #{node} uptime`
    reply
  end
end

ruote.register 'grab_uptime', GrabUptime

pdef =
  Ruote.define do
    concurrent_iterator :on => %w[ n1 n2 n3 n4 n5 ], :mt => :union do
      grab_uptime :node => '${v:i}'
    end
  end

wfid = ruote.launch(pdef)

# ...