Extracts attachment change handler to module

app/models/message.rb

@@ -29,6 +29,8 @@
 
 class Message < ActiveRecord::Base
   include Redmine::SafeAttributes
+  include OpenProject::Journal::AttachmentHelper
+
   belongs_to :board
   belongs_to :author, :class_name => 'User', :foreign_key => 'author_id'
   acts_as_tree :counter_cache => :replies_count, :order => "#{Message.table_name}.created_on ASC"
@@ -133,12 +135,4 @@ class Message < ActiveRecord::Base
     watchers(true)
     watcher_users(true)
   end
-
-  # ACTS AS ATTACHABLE
-  def attachments_changed(obj)
-    unless new_record?
-      add_journal
-      save!
-    end
-  end
 end

app/models/work_package.rb

@@ -36,6 +36,8 @@ class WorkPackage < ActiveRecord::Base
   include WorkPackage::SchedulingRules
   include WorkPackage::StatusTransitions
 
+  include OpenProject::Journal::AttachmentHelper
+
   # >>> issues.rb >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
   include Redmine::SafeAttributes
 
@@ -283,14 +285,6 @@ class WorkPackage < ActiveRecord::Base
     !due_date.nil? && (due_date < Date.today) && !status.is_closed?
   end
 
-  # ACTS AS ATTACHABLE
-  def attachments_changed(obj)
-    unless new_record?
-      add_journal
-      save
-    end
-  end
-
   # ACTS AS JOURNALIZED
   def activity_type
     "work_packages"

lib/open_project/journal/attachment_helper.rb

@@ -0,0 +1,41 @@
+#-- encoding: UTF-8
+#-- copyright
+# OpenProject is a project management system.
+# Copyright (C) 2012-2013 the OpenProject Foundation (OPF)
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License version 3.
+#
+# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
+# Copyright (C) 2006-2013 Jean-Philippe Lang
+# Copyright (C) 2010-2013 the ChiliProject Team
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+#
+# See doc/COPYRIGHT.rdoc for more details.
+#++
+
+module OpenProject
+  module Journal
+    module AttachmentHelper
+      def attachments_changed(obj)
+        unless new_record?
+          add_journal
+          save
+        end
+      end
+    end
+  end
+end