DRY code. always a pleasure to see it in the wild

lib/report/chainable.rb

@@ -78,6 +78,10 @@ class Report < ActiveRecord::Base
       engine.chain_initializer.push block
     end
 
+    def self.cache_key
+      @cache_key ||= underscore_name
+    end
+
     inherited_attribute :label, :default => :translation_needed
     inherited_attribute :properties, :list => true
 

lib/report/filter/base.rb

@@ -16,10 +16,6 @@ class Report::Filter
 
     attr_accessor :values
 
-    def self.cache_key
-      @cache_key ||= underscore_name
-    end
-
     def cache_key
       self.class.cache_key + operator.to_s + Array(values).join(',')
     end

lib/report/group_by/base.rb

@@ -16,10 +16,6 @@ class Report::GroupBy
       child.filter?
     end
 
-    def self.cache_key
-      @cache_key ||= underscore_name
-    end
-
     def cache_key
       self.class.cache_key + type.to_s[0,1]
     end