lib/ruote/part/block_participant.rb in ruote-2.2.0 vs lib/ruote/part/block_participant.rb in ruote-2.3.0

@@ -1,7 +1,7 @@
 #--
-# Copyright (c) 2005-2011, John Mettraux, [e-mail]
+# Copyright (c) 2005-2012, John Mettraux, [e-mail]
 #
 # 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
@@ -20,13 +20,11 @@
 # THE SOFTWARE.
 #
 # Made in Japan.
 #++
 
-require 'ruote/part/local_participant'
 
-
 module Ruote
 
   #
   # One of the simplest participants. Simply passes a workitem to a block
   # of ruby code.
@@ -46,23 +44,24 @@
   #
   #
   # == do_not_thread
   #
   # By default, this participant (like most other participants) is executed
-  # in its own thread (in a Ruby runtime where EventMachine is running,
-  # EM.next_tick is used instead of a new thread).
+  # in its own thread.
   #
-  # You can change that behaviour (beware block thats monopolises the whole
-  # engine !) by doing
   #
-  #   alpha = engine.register_participant :alpha do |workitem|
-  #     workitem.fields['time'] = Time.now
-  #   end
+  # == context
   #
-  #   alpha.do_not_thread = true
+  # As it includes Ruote::LocalParticipant, the block partitcipant has
+  # access to:
   #
-  # (you could also override do_not_thread, the method ...)
+  # * #context: the ruote context
+  # * #workitem: the current workitem (usually passed as arg to the block)
+  # * #fei: the current flow expression id
+  # * #fexp: the current flow expression
+  # * #flavour: only used in #on_cancel (nil or 'kill')
+  # * #lookup_variable(key): looks up a variable...
   #
   class BlockParticipant
 
     include LocalParticipant
 
@@ -71,30 +70,18 @@
     def initialize(opts)
 
       @opts = opts
     end
 
-    def do_not_thread
+    def on_workitem
 
-      @opts['do_not_thread']
-    end
+      block = get_block('on_workitem', 'block')
 
-    def consume(workitem)
-
-      block = @opts['block']
-
-      @context.treechecker.block_check(block)
-        # raises in case of 'security' violation
-
-      #block = eval(block, @context.send(:binding))
-        # doesn't work with ruby 1.9.2-p136
-      block = eval(block, @context.instance_eval { binding })
-        # works OK with ruby 1.8.7-249 and 1.9.2-p136
-
       r = if block.arity == 1
 
         block.call(workitem)
+
       else
 
         block.call(
           workitem, Ruote::Exp::FlowExpression.fetch(@context, workitem.h.fei))
       end
@@ -106,10 +93,60 @@
       reply_to_engine(workitem)
     end
 
     def cancel(fei, flavour)
 
-      # do nothing
+      if block = get_block('on_cancel')
+        block.call(fei, flavour)
+      end
+    end
+
+    def on_reply(workitem)
+
+      if block = get_block('on_reply')
+        block.call(workitem)
+      end
+    end
+
+    def accept?(workitem)
+
+      if block = get_block('accept?')
+        block.call(workitem)
+      else
+        true
+      end
+    end
+
+    def do_not_thread(workitem)
+
+      dnt = @opts['do_not_thread']
+
+      return dnt unless dnt.is_a?(String)
+
+      block = get_block('do_not_thread')
+
+      block.call(workitem)
+    end
+
+    protected
+
+    def get_block(*keys)
+
+      key = keys.find { |k| @opts[k] }
+
+      return nil unless key
+
+      block = @opts[key]
+
+      @context.treechecker.block_check(block)
+        # raises in case of 'security' violation
+
+      #eval(block, @context.send(:binding))
+        # doesn't work with ruby 1.9.2-p136
+      #eval(block, @context.instance_eval { binding })
+        # works OK with ruby 1.8.7-249 and 1.9.2-p136
+      eval(block, self.instance_eval { binding })
+        # works OK with ruby 1.8.7-249 and 1.9.2-p136
     end
   end
 end