reintroduction of the 'listener' concept : lib/ruote/part/listener.rb

CHANGELOG.txt

@@ -4,6 +4,7 @@
 
 == ruote - 2.1.10    not yet released
 
+- reintroduction of the 'listener' concept : lib/ruote/part/listener.rb
 - LocalParticpant : added a reject(workitem) method
 - participant exp : dispatched = true set right after dispatch
 

lib/ruote/part/listener.rb

@@ -0,0 +1,71 @@
+#--
+# Copyright (c) 2005-2010, John Mettraux, jmettraux@gmail.com
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+#
+# Made in Japan.
+#++
+
+
+module Ruote
+
+  #
+  # Listening to workitems coming [back] to the engine.
+  #
+  # This module contains the base methods necessary for a Listener
+  # implementation.
+  #
+  # This module is included in the LocalParticipant one. The reply_to_engine
+  # method is present in both concepts.
+  #
+  # Hypothetically, a listener implementation might look like :
+  #
+  #   require 'ruote/part/listener'
+  #
+  #   class MyMqListener
+  #     include Ruote::Listener
+  #     def initialize (queue)
+  #       @queue = queue
+  #     end
+  #     def start_pooling
+  #       while workitem = @queue.blocking_pop
+  #         reply_to_engine(workitem)
+  #       end
+  #     end
+  #   end
+  #
+  module Listener
+
+    attr_accessor :context
+
+    # Sends back the workitem to the ruote engine.
+    #
+    def reply_to_engine (workitem)
+
+      # the local participant knows how to deal with the storage directly
+
+      @context.storage.put_msg(
+        'receive',
+        'fei' => workitem.h.fei,
+        'workitem' => workitem.h,
+        'participant_name' => workitem.participant_name)
+    end
+  end
+end
+

lib/ruote/part/local_participant.rb

@@ -22,6 +22,8 @@
 # Made in Japan.
 #++
 
+require 'ruote/part/listener'
+
 
 module Ruote
 
@@ -35,20 +37,8 @@ module Ruote
   #
   module LocalParticipant
 
-    attr_accessor :context
-
-    # Sends back the workitem to the ruote engine.
-    #
-    def reply_to_engine (workitem)
-
-      # the local participant knows how to deal with the storage directly
-
-      @context.storage.put_msg(
-        'receive',
-        'fei' => workitem.h.fei,
-        'workitem' => workitem.h,
-        'participant_name' => workitem.participant_name)
-    end
+    include Listener
+      # the reply_to_engine method is there
 
     # WARNING : this method is only for 'stateless' participants, ie
     # participants that are registered in the engine by passing their class