Rails 3.1 limit user created objects

Question

I would like to limit the number of model Objects a user can create. I\'ve tried the below but it is not working. I understand some changes have happened in rails 3.1 and

Answer 1

Try something like this:

class User < ActiveRecord::Base
  has_many :things
end

class Things  :create

  def thing_count_within_limit
    if self.user.things(:reload).count >= 5
      errors.add(:base, "Exceeded thing limit")
    end
  end
end

Edit: updated for Rails 3