Methods
Instance Public methods
serialize(attr_name, class_name = Object)
Link
If you have an attribute that needs to be saved to the database as an
object, and retrieved as the same object, then specify the name of that
attribute using this method and it will be handled automatically. The
serialization is done through YAML. If class_name
is
specified, the serialized object must be of that class on retrieval or
SerializationTypeMismatch
will be raised.
A notable side effect of serialized attributes is that the model will be updated on every save, even if it is not dirty.
Parameters
-
attr_name
- The field name that should be serialized. -
class_name
- Optional, class name that the object type should be equal to.
Example
# Serialize a preferences attribute.
class User < ActiveRecord::Base
serialize :preferences
end
# File activerecord/lib/active_record/attribute_methods/serialization.rb, line 41 def serialize(attr_name, class_name = Object) include Behavior coder = if [:load, :dump].all? { |x| class_name.respond_to?(x) } class_name else Coders::YAMLColumn.new(class_name) end # merge new serialized attribute and create new hash to ensure that each class in inheritance hierarchy # has its own hash of own serialized attributes self.serialized_attributes = serialized_attributes.merge(attr_name.to_s => coder) end