Returns true
if the provided attribute is being cached.
# File lib/active_record/attribute_methods/read.rb, line 34 def cache_attribute?(attr_name) cached_attributes.include?(attr_name) end
cache_attributes
allows you to declare which converted
attribute values should be cached. Usually caching only pays off for
attributes with expensive conversion methods, like time related columns
(e.g. created_at
, updated_at
).
# File lib/active_record/attribute_methods/read.rb, line 22 def cache_attributes(*attribute_names) attribute_names.each {|attr| cached_attributes << attr.to_s} end
Returns the attributes which are cached. By default time related columns
with datatype :datetime, :timestamp, :time, :date
are cached.
# File lib/active_record/attribute_methods/read.rb, line 28 def cached_attributes @cached_attributes ||= columns.select{|c| attribute_types_cached_by_default.include?(c.type)}.map{|col| col.name}.to_set end
# File lib/active_record/attribute_methods/read.rb, line 39 def define_method_attribute(attr_name) if self.serialized_attributes[attr_name] define_read_method_for_serialized_attribute(attr_name) else define_read_method(attr_name, attr_name, columns_hash[attr_name]) end if attr_name == primary_key && attr_name != "id" define_read_method('id', attr_name, columns_hash[attr_name]) end end