read_attribute

# File activerecord/lib/active_record/attribute_methods/read.rb, line 29
      def read_attribute(attr_name, &block)
        name = attr_name.to_s
        name = self.class.attribute_aliases[name] || name

        return @attributes.fetch_value(name, &block) unless name == "id" && @primary_key

        if self.class.composite_primary_key?
          @attributes.fetch_value("id", &block)
        else
          if @primary_key != "id"
            ActiveRecord.deprecator.warn(              Using read_attribute(:id) to read the primary key value is deprecated.              Use #id instead..squish)
          end
          @attributes.fetch_value(@primary_key, &block)
        end
      end