basic_amoeba_setup

class Post < ActiveRecord::Base
  has_many   :comments
  belongs_to :approved_version, class_name: name
  has_one    :draft, class_name: name, foreign_key: :approved_version_id

  amoeba do
    include_association :comments
    exclude_association [:approved, :draft]

    customize(lambda {|live_obj, draft_obj|
      # This only sets approved_version_id on Post model, doesn't get passed down to its child comments
      draft_obj.approved_version_id = live_obj.id
    })
  end
end

class Comment < ActiveRecord::Base
  belongs_to :post
  has_many   :ratings
  belongs_to :approved_version, class_name: name
  has_one    :draft, class_name: name, foreign_key: :approved_version_id

  amoeba do
    include_association :ratings
    exclude_association [:approved, :draft]

    customize(lambda {|live_obj, draft_obj|
      # This only sets approved_version_id on Comment model, doesn't get passed down to its child ratings
      draft_obj.approved_version_id = live_obj.id
    })
  end
end

class Rating < ActiveRecord::Base
  belongs_to :comment
  belongs_to :approved_version, class_name: name
  has_one    :draft, class_name: name, foreign_key: :approved_version_id
  # Ah crap, the approved_version_id isn't getting set
end