ruby-on-rails - 在销毁相关模型更新之前，错误不会传播

Question

我有一个父模型，它正在通过像“@client.update_attributes(params[:client]”这样的参数进行更新。在我的参数中是一个销毁“client_card”的调用。我在 client_card 上有一个 before_destroy 方法防止它被销毁等。我的 before_destroy 方法正在运行，但是，before_destroy 上的错误在更新时不会传播到相关模型。关于如何在更新时将此模型错误传播到关联模型有什么建议吗？

class Client < ActiveRecord::Base
  has_many :client_cards, :dependent => :destroy
  validates_associated :client_cards

class ClientCard < ActiveRecord::Base
  belongs_to :client, :foreign_key => 'client_id'

  attr_accessible :id, :client_id, :card_hash, :last_four, :exp_date

  before_destroy :check_relationships

  def check_finished_appointments
    appointments = Appointment.select { |a| a.client_card == self && !a.has_started }
    if(appointments && appointments.length > 0 )
      errors.add(:base, "This card is tied to an appointment that hasn't occurred yet.")
      return false
    else
      return true
    end
  end

end

Answer 1

我怀疑validates_associated只对 ClientCard 运行显式声明的验证，并且不会触发您在 before_destroy 中添加的错误打回来。您最好的选择可能是 before_update回调Client :

class Client < ActiveRecord::Base
  has_many :client_cards, :dependent => :destroy

  before_update :check_client_cards

  # stuff

  def check_client_cards
    if client_cards.any_future_appointments?
      errors.add(:base, "One or more client cards has a future appointment.")
    end
  end
end

然后 ClientCard :

class ClientCard < ActiveRecord::Base
  belongs_to :client, :foreign_key => 'client_id'

  # stuff

  def self.any_future_appointments?
    all.detect {|card| !card.check_finished_appointments }
  end
end