A base class for process observers, just to provide convenience. It (heavily) sugar coats the Ruote::Observer and translate the messages into actions. Each such action is provided with pre-distilled information relevant for processes.

Example implementation

  class WebsocketSubscriber < Ruote::ProcessObserver
     # override initialize to warm-up a websocket client
     def initialize(context, options={})
       super
       @client = WebsocketClient.new()
     end

     # tell the listeners that a new process launched
     def on_launch(wfid, opts)
       @client.publish(
         "/process/launch",
         { :name       => opts[:workitem].wf_name,
           :wfid       => wfid,
           :definition => opts[:pdef],
         }
       )
     end

     # tell the listeners that a new process ended
     def on_end(wfid)
       @client.publish("/process/#{wfid}", { :end => true })
     end
  end

Actions

The ProcessObserver adheres closely to the message actions, it calls the following methods:

And others, but if you are interested in those; you might be better of using the more low-level Ruote::Observer

Arguments

The methods are called with (wfid[, options])

You can provide a method-signature like:

  def on_launch(wfid, options)
  def on_launch(wfid)

If the ProcessObserver cannot call the method with the options, it tries to call without options

Options

The following options are provided:

Error handling

If anywhere in your implementation an action raises an error, it is caught by the ProcessObserver and silently ignored.