When subclassing - why isn't _type returned on query?

[cmc476]

ie...

class Pet
  include Mongoid::Document
  field :name, type: String
end

class Dog < Pet
  field :breed, type: String
  field :average_weight, type: Integer
end

class Cat < Pet
  field :minion_strength, type: Integer
end

get '/pets' do
  Pet.all.to_json
end

get returns all attributes but _type...though it's in db.

[p-mongo]

Hi @cmc476 ,

I'm not sure why this is Mongoid's behavior, but if ActiveRecord does return its STI class value in the equivalent scenario we would consider changing Mongoid to match.

[neilshweky]

Hi there! I have created the following jira ticket to investigate your report: https://jira.mongodb.org/browse/MONGOID-5367

[neilshweky]

Hi there, after some investigation I have found that there is a Mongoid configuration option called include_type_for_serialization which, when set to true, will include the _type field in the results of as_json. You can set it as follows:

Mongoid.include_type_for_serialization = true

or in your mongoid.yml.