Example subscription decorator structure.

example.rb

class ChargifySubscription < SimpleDelegator
  def addons_count
    # Implementacion aqui
  end
  
  def price
    # Implementacion aqui
  end
end

class BraintreeSubscription  < SimpleDelegator

  def addons_count
    # Implementacion aqui
  end
  
  def price
    # Implementacion aqui
  end
end


class Subscription
  attr_accessible :api

  def addons_count
    decorate.addons_count
  end
  
  def price
    decorate.price
  end

  def decorate
    if api == "braintree"
      BraintreeSubscription.new(self)
    elsif api == "chargify"
      ChargifySubscription.new(self)
    end
  end