reuse code for copying attributes from Chef object

libraries/pacemaker/cib_object.rb

@@ -67,6 +67,15 @@ module Pacemaker
           obj
         end
       end
+
+      def from_chef_resource(resource)
+        new(resource.name).copy_attrs_from_chef_resource(resource,
+                                                         *attrs_to_copy_from_chef)
+      end
+
+      def attrs_to_copy_from_chef
+        raise NotImplementedError, "#{self.class} didn't implement attrs_to_copy_from_chef"
+      end
     end
 
     def initialize(name)

libraries/pacemaker/constraint/colocation.rb

@@ -6,9 +6,8 @@ class Pacemaker::Constraint::Colocation < Pacemaker::Constraint
 
   attr_accessor :score, :resources
 
-  def self.from_chef_resource(resource)
-    attrs = %w(score resources)
-    new(resource.name).copy_attrs_from_chef_resource(resource, *attrs)
+  def self.attrs_to_copy_from_chef
+    %w(score resources)
   end
 
   def parse_definition

libraries/pacemaker/resource.rb

@@ -49,6 +49,5 @@ module Pacemaker
       end
       h
     end
-
   end
 end

libraries/pacemaker/resource/group.rb

@@ -9,9 +9,8 @@ class Pacemaker::Resource::Group < Pacemaker::Resource
 
   attr_accessor :members
 
-  def self.from_chef_resource(resource)
-    attrs = %w(members meta)
-    new(resource.name).copy_attrs_from_chef_resource(resource, *attrs)
+  def self.attrs_to_copy_from_chef
+    %w(members meta)
   end
 
   def parse_definition

libraries/pacemaker/resource/primitive.rb

@@ -16,8 +16,8 @@ class Pacemaker::Resource::Primitive < Pacemaker::Resource
     @agent = nil
   end
 
-  def self.from_chef_resource(resource)
-    new(resource.name).copy_attrs_from_chef_resource(resource, *%w(agent params meta op))
+  def self.attrs_to_copy_from_chef
+    %w(agent params meta op)
   end
 
   def parse_definition