When using discriminator_value on child classes, it throws an exception when trying to retrieve that document from the parent class.
ie.:
class Parent include Mongoid::Document end class Child < Parent self.discriminator_value = 'ch' end
So if I create a record, I can retrieve the record from both child and parent class:
> Child.create => #<Child _id: 5fd29615a50a9012f69d1255 > > Child.last => #<Child _id: 5fd29615a50a9012f69d1255 > > Parent.last => #<Child _id: 5fd29615a50a9012f69d1255 >
However, if I terminate the console session and start again, I get the following:
~ rails c > Parent.last Mongoid::Errors::UnknownModel () message: Attempted to instantiate an object of the unknown model 'Ch'. summary: A document with the value 'ch' at the key '_type' was used to instantiate a model object but Mongoid cannot find the Class. resolution: The _type field is a reserved one used by Mongoid to determine the class for instantiating an object. Please don't save data in this field or ensure that any values in this field correspond to valid Models. > Child.last => #<Children _id: 5fd29615a50a9012f69d1255 > > Parent.last => #<Child _id: 5fd29615a50a9012f69d1255 >
- is caused by
-
MONGOID-4816 Inheritance: Allow override of discriminator values in _type field used to denote subclass
-
- Released
-
- links to