Added ActiveRecord::Base#to_json/from_json (currently does not support :include like to_xml) [DHH]. Added ActiveRecord::Base#from_xml [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7519 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 59 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/serialization.rb b/activerecord/lib/active_record/serialization.rb
new file mode 100644
index 0000000000..f10d1b3b7e
--- /dev/null
+++ b/activerecord/lib/active_record/serialization.rb
@@ -0,0 +1,59 @@
+module ActiveRecord #:nodoc:
+  module Serialization
+    class Serializer #:nodoc:
+      attr_reader :options
+    
+      def initialize(record, options = {})
+        @record, @options = record, options.dup
+      end
+
+      # To replicate the behavior in ActiveRecord#attributes,
+      # :except takes precedence over :only.  If :only is not set
+      # for a N level model but is set for the N+1 level models,
+      # then because :except is set to a default value, the second
+      # level model can have both :except and :only set.  So if
+      # :only is set, always delete :except.
+      def serializable_attribute_names
+        attribute_names = @record.attribute_names
+
+        if options[:only]
+          options.delete(:except)
+          attribute_names = attribute_names & Array(options[:only]).collect { |n| n.to_s }
+        else
+          options[:except] = Array(options[:except]) | Array(@record.class.inheritance_column)
+          attribute_names = attribute_names - options[:except].collect { |n| n.to_s }
+        end
+      
+        attribute_names
+      end
+
+      def serializable_method_names
+        Array(options[:methods]).inject([]) do |method_attributes, name|
+          method_attributes << :name if @record.respond_to?(name.to_s)
+          method_attributes
+        end
+      end
+      
+      def serializable_names
+        serializable_attribute_names + serializable_method_names
+      end
+
+      def serializable_record
+        returning(serializable_record = {}) do
+          serializable_names.each { |name| serializable_record[name] = @record.send(name) }
+        end
+      end
+
+      def serialize
+        # overwrite to implement
+      end        
+    
+      def to_s(&block)
+        serialize(&block)
+      end
+    end
+  end
+end
+
+require 'active_record/serializers/xml_serializer'
+require 'active_record/serializers/json_serializer'
\ No newline at end of file