cache.rb in ar-simple-idmap-0.2.4

- old
+ new
@@ -1,89 +1,116 @@
-module ActiveRecord
-  class Base
-  	module ThreadIdentityMap
-	  class ClassIdMap
-		def initialize(klass)
-		  @objects = {}
-		  @object = klass.allocate
-		  @object.instance_variable_set(:@attributes, {:id=>nil})
-		  @object.instance_variable_set(:@attributes_cache, {})
-		end
-		
-		def [](id)
-		  @object.id = id
-		  @objects[@object.id]
-		end
-		
-		def []=(id, v)
-		  @object.id = id
-		  @objects[@object.id] = v
-		end
-		
-		def delete(id)
-		  @object.id = id
-		  @objects.delete(@object.id)
-		end
-	  end
-	  
-	  class IdMap
-	  
-		def initialize
-		  @objects = {}
-		end
-	  
-		def for_class(klass)
-		  @objects[ klass.base_class ] ||= ClassIdMap.new(klass)
-		end
-		
-	  end
-	  
-	  module ClassMethods
-	  	def create_identity_map
-	  	  set_thread_id_map IdMap.new
-	  	end
-	  	
-	  	def drop_identity_map
-	  	  set_thread_id_map nil
-	  	end
-	  	
-		def with_id_map( fresh = true)
-		  old = thread_id_map
-		  create_identity_map if fresh || old.nil?
-		  yield
-		ensure
-		  set_thread_id_map old
-		end
-		
-		def without_id_map
-		  old = thread_id_map
-		  drop_identity_map
-		  yield
-		ensure
-		  set_thread_id_map old
-		end
-		
-#		def uncached_with_identity_map( &block )
-#		  without_id_map do
-#		  	uncached_without_identity_map &block
-#		  end
-#		end
-		
-		protected
-		
-		  def thread_id_map
-			Thread.current[:ar_identity_map]
-		  end
-		  
-		  def thread_id_map=(v)
-			Thread.current[:ar_identity_map] = v
-		  end
-		  
-		  alias set_thread_id_map thread_id_map=
-		
-	  end
+module ActiveRecord # :nodoc:
+  class Base # :nodoc:
+    module ThreadIdentityMap # :nodoc:
+      # ClassIdMap do the job of properly use typecasted +id+ value of model object
+      # for search in a cache
+      class ClassIdMap
+        def initialize(klass)
+          @objects = {}
+          @object = klass.allocate
+          @object.instance_variable_set(:@attributes, {:id=>nil})
+          @object.instance_variable_set(:@attributes_cache, {})
+        end
+        
+        def [](id)
+          @object.id = id
+          @objects[@object.id]
+        end
+        
+        def []=(id, v)
+          @object.id = id
+          @objects[@object.id] = v
+        end
+        
+        def delete(id)
+          @object.id = id
+          @objects.delete(@object.id)
+        end
+      end
+      
+      # Manages separated object caches for each model
+      class IdMap
+      
+        def initialize
+          @objects = {}
+        end
+      
+        def for_class(klass)
+          @objects[ klass.base_class ] ||= ClassIdMap.new(klass)
+        end
+        
+      end
+      
+      module ClassMethods
+        # Creates new identity map and put it in thread local storage
+        #
+        # For most use cases +with_id_map+ should be used instead.
+        #
+        # Usage:
+        #   ActiveRecord::Base.create_identity_map
+        def create_identity_map
+          set_thread_id_map IdMap.new
+        end
+        
+        # Remove identity map from thread local storage
+        #
+        # For most use cases +without_id_map+ should be used instead.
+        #
+        # Usage:
+        #   ActiveRecord::Base.drop_identity_map
+        def drop_identity_map
+          set_thread_id_map nil
+        end
+        
+        # Execute block with identity map.
+        #
+        # If it called with +true+, then new instance of identity map would be used
+        # regardless of any present.
+        #
+        # If it called with +false+, then it only ensures that identity map created if absent.
+        #
+        # Default is +true+
+        #
+        # Usage:
+        #   ActiveRecord::Base.with_id_map do
+        #     #do_some_actions
+        #   end
+        def with_id_map( fresh = true)
+          old = thread_id_map
+          create_identity_map if fresh || old.nil?
+          yield
+        ensure
+          set_thread_id_map old
+        end
+        
+        # Execute block with identity map turned off.
+        #
+        # Usage:
+        #   ActiveRecord::Base.without_id_map do
+        #     #do_some_actions
+        #   end
+        def without_id_map
+          old = thread_id_map
+          drop_identity_map
+          yield
+        ensure
+          set_thread_id_map old
+        end
+        
+        protected
+        
+          def thread_id_map
+            Thread.current[:ar_identity_map]
+          end
+          
+          def thread_id_map=(v)
+            Thread.current[:ar_identity_map] = v
+          end
+          
+          alias set_thread_id_map thread_id_map=
+        
+      end
     end
-	
-	extend ThreadIdentityMap::ClassMethods
-#	self.class.send :alias_method_chain, :uncached, :identity_map
+    
+    extend ThreadIdentityMap::ClassMethods
   end
 end