fe_misc.rb in ruote-0.9.20

- old
+ new

@@ -1,43 +1,29 @@
-#
 #--
-# Copyright (c) 2006-2008, John Mettraux, OpenWFE.org
-# All rights reserved.
+# Copyright (c) 2006-2009, John Mettraux, jmettraux@gmail.com
 #
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are met:
+# 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:
 #
-# . Redistributions of source code must retain the above copyright notice, this
-#   list of conditions and the following disclaimer.
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
 #
-# . Redistributions in binary form must reproduce the above copyright notice,
-#   this list of conditions and the following disclaimer in the documentation
-#   and/or other materials provided with the distribution.
+# 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.
 #
-# . Neither the name of the "OpenWFE" nor the names of its contributors may be
-#   used to endorse or promote products derived from this software without
-#   specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
-# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
-# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-# POSSIBILITY OF SUCH DAMAGE.
+# Made in Japan.
 #++
-#
 
-#
-# "made in Japan"
-#
-# John Mettraux at openwfe.org
-#
 
 require 'openwfe/expressions/flowexpression'
 require 'openwfe/expressions/value'
 require 'openwfe/util/treechecker'
 
@@ -81,11 +67,11 @@
 
       set_variable(vname, text)
       set_variable(DESC, text) unless lookup_variable(DESC)
         # set default if not set
 
-      reply_to_parent workitem
+      reply_to_parent(workitem)
     end
   end
 
   #
   # A debug/test expression (it's mostly used in the test suite
@@ -109,11 +95,11 @@
   # OpenWFEru test suite uses this expression).
   #
   class PrintExpression < FlowExpression
     include ValueMixin
 
-    names :print
+    names :print, :echo
 
     def reply (workitem)
 
       text = workitem.get_result.to_s
       text << "\n"
@@ -124,11 +110,11 @@
         tracer << text
       else
         puts text
       end
 
-      reply_to_parent workitem
+      reply_to_parent(workitem)
     end
   end
 
   #
   # Evals some Ruby code contained within the process definition
@@ -160,19 +146,34 @@
   #       """
   #     end
   #   end
   #
   # Don't embed too much Ruby into your process definitions, it might
-  # hurt...
+  # hurt... It's probably better to embed some ruby code in a BlockParticipant,
+  # like in
   #
+  #   engine.register_participant :compute_total do |workitem|
+  #     sum = workitem.items.inject(0) do |sum, item|
+  #       sum += item['count'] * item['price']
+  #     end
+  #   end
+  #
+  # 2 advantages : not too much ruby code in the process definition, and the
+  # participant can be reused for another process.
+  #
   # Reval can also be used with the 'code' attribute (or 'field-code' or
   # 'variable-code') :
   #
   #   <reval field-code="f0" />
   #
   # to eval the Ruby code held in the field named "f0".
   #
+  # Note that currently, the actual evaluation of the ruby code is done in
+  # the work thread, so while this ruby code is executing, there is no
+  # chance for other process instances to progress. Using a block participant
+  # (like explained a few paragraphs up here) avoids this problem altogether.
+  #
   class RevalExpression < FlowExpression
     include ValueMixin
 
     names :reval
 
@@ -186,18 +187,18 @@
       code = code.to_s
 
       wi = workitem
         # so that the ruby code being evaluated sees 'wi' and 'workitem'
 
-      get_tree_checker.check code
+      get_tree_checker.check(code)
 
-      result = eval code, binding()
+      result = eval(code, binding())
 
       workitem.set_result(result) \
         if result != nil  # as 'false' is a valid result
 
-      reply_to_parent workitem
+      reply_to_parent(workitem)
     end
   end
 
   #
   # An advanced expression : it takes the value in a field or variable (or
@@ -222,45 +223,25 @@
   class EvalExpression < FlowExpression
     include ValueMixin
 
     names :eval
 
-
     def reply (workitem)
 
-      raise "dynamic evaluation of process definitions is not allowed" \
+      raise 'dynamic evaluation of process definitions is not allowed' \
         if @application_context[:dynamic_eval_allowed] != true
 
       df = lookup_vf_attribute(workitem, 'def') || workitem.get_result
 
       return reply_to_parent(workitem) unless df
         #
         # currently, 'nothing to eval' means, 'just go on'
 
-      ldebug { "apply() def is >#{df}<" }
+      tree = get_def_parser.determine_rep(df)
 
-      raw_expression = build_raw_expression df
-
-      #puts
-      #puts "======================================"
-      #puts raw_expression.to_s
-      #puts raw_expression.raw_representation
-      #puts "======================================"
-      #puts
-
-      raw_expression.apply workitem
+      get_expression_pool.substitute_and_apply(self, tree, workitem)
     end
-
-    protected
-
-      def build_raw_expression (df)
-
-        procdf = get_expression_pool.determine_rep df
-
-        RawExpression.new_raw(
-          fei, parent_id, environment_id, application_context, procdf)
-      end
   end
 
   #
   # Some kind of limited 'eval' expression.
   #
@@ -296,77 +277,57 @@
   #
   class ExpExpression < RawExpression
 
     names :exp
 
-    #--
-    #def initialize (fei, parent_id, env_id, app_context, att)
-    #  #
-    #  # this responds to the FlowExpression constructor...
-    #  super fei, parent_id, env_id, app_context, nil
-    #    #
-    #    # but this triggers the RawExpression constructor :)
-    #  @attributes = att
-    #    #
-    #    # as this is not done by the RawExpression constructor
-    #end
-    #++
-
     def apply (workitem)
 
       @applied_workitem = workitem
 
       super
     end
 
     protected
 
-      #
-      # Evaluates the 'name' attribute, if it's not present or empty,
-      # will return the value for the 'default' attribute.
-      #
-      def expression_name
+    #
+    # Evaluates the 'name' attribute, if it's not present or empty,
+    # will return the value for the 'default' attribute.
+    #
+    def expression_name
 
-        n = lookup_attribute :name, @applied_workitem
+      n = lookup_attribute(:name, @applied_workitem)
 
-        return lookup_attribute(:default, @applied_workitem) \
-          if (not n) or (n.strip == '')
+      return lookup_attribute(:default, @applied_workitem) \
+        if (not n) or (n.strip == '')
+      n
+    end
 
-        n
-      end
+    #
+    # If the 'attributes' attribute is present, will return its
+    # value. Else, will simply return the attributes of the 'exp'
+    # expression itself ('name' and 'default' included).
+    #
+    def extract_attributes
 
-      #
-      # If the 'attributes' attribute is present, will return its
-      # value. Else, will simply return the attributes of the 'exp'
-      # expression itself ('name' and 'default' included).
-      #
-      def extract_attributes
+      att = lookup_vf_attribute(@applied_workitem, :attributes)
+        # will currently only work with an attribute hash
+        # whose keys are strings... symbols :(
 
-        att = lookup_vf_attribute @applied_workitem, :attributes
-          # will currently only work with an attribute hash
-          # whose keys are strings... symbols :(
+      att || @attributes
+    end
 
-        att || @attributes
-      end
+    def extract_children
+      @children
+    end
 
-      #--
-      #def extract_descriptions
-      #  []
-      #end
-      #++
-
-      def extract_children
-        @children
-      end
-
-      def extract_parameters
-        []
-      end
+    def extract_parameters
+      []
+    end
   end
 
   #
   # This expression simply emits a message to the application
-  # log (by default logs/openwferu.log).
+  # log (by default logs/ruote.log).
   #
   #   <sequence>
   #     <log>before participant alpha</log>
   #     <participant ref="alpha" />
   #     <log>after participant alpha</log>