Methods
Instance Public methods
serialize(attr_name, class_name_or_coder = 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.
Parameters
-
attr_name
- The field name that should be serialized. -
class_name_or_coder
- Optional, a coder object, which responds to `.load` / `.dump` or a class name that the object type should be equal to.
Example
# Serialize a preferences attribute.
class User < ActiveRecord::Base
serialize :preferences
end
# Serialize preferences using JSON as coder.
class User < ActiveRecord::Base
serialize :preferences, JSON
end
# Serialize preferences as Hash using YAML coder.
class User < ActiveRecord::Base
serialize :preferences, Hash
end
# File activerecord/lib/active_record/attribute_methods/serialization.rb, line 49 def serialize(attr_name, class_name_or_coder = Object) include Behavior coder = if [:load, :dump].all? { |x| class_name_or_coder.respond_to?(x) } class_name_or_coder else Coders::YAMLColumn.new(class_name_or_coder) 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