Single Table Inheritance and 'type' value for namespaced classes

Question

While working on Rails 2.3.18 to Rails 3.2.x migration I am facing name issue in type column

Here is the relation that is defined.

app/models/reservation.rb

class Reservation
end

class Reservation::Guest < Reservation
end

class Reservation::Event < Reservation
end

While saving Reservation::Guest Or Reservation::Event instance, the type value being saved is Reservation::Guest and Reservation::Event in Rails 3. But in Rails 2 it saves without namespace i.e., Guest or Event.

It requires lots of efforts to migrate existing data and change all the places which expects type without namespace.

Would it be possible to save type without namespace and rest work without making lots of modification across the application?

Answer 1

Take a look at sti_name and find_sti_class. (The methods responsible for setting and getting the sti_name)

---

You can customize them as follows:

class Reservation
  def self.find_sti_class(type_name)
    type_name = self.name
    super
  end
end

class Reservation::Guest < Reservation
  def self.sti_name
    "Guest"
  end
end

class Reservation::Event < Reservation
  def self.sti_name
    "Event"
  end
end