Rails 嵌套模型验证问题

Rails nested model validation issue

我有以下包含一些验证的收件人模型(为了简单起见,只显示前 2 个):

 class Recipient < ActiveRecord::Base
  belongs_to :offer
  belongs_to :offer_acceptance
  validates :name, presence: true
  validates :aba_transit_number, presence: true, aba_checksum: true, format: { with: /\A((0[0-9])|(1[0-2])|(2[1-9])|(3[0-2])|(6[1-9])|(7[0-2])|80)([0-9]{7})\Z/, message: "has an invalid format" },  if: "to_usd?"

  def belongs_to_offer?
    #Check if recipient is from offer
    offer_id != nil && offer_acceptance_id == nil
  end

  def to_usd?
    (belongs_to_offer? && offer && offer.currency_to === "usd") || (!belongs_to_offer? &&  offer_acceptance && offer_acceptance.offer.currency_from === "usd")
  end
...

这是报价模型

class Offer < ActiveRecord::Base
  has_one :recipient
  accepts_nested_attributes_for :recipient
  validates_associated :recipient
  ....

如您所见,aba_transit_number 验证仅在 recipient.offer.currency_to === "usd" 时发生。 当我像这样在控制台上创建一个新的收件人时,验证工作正常:

o = Offer.create!(currency_to: "usd")
r = Recipient.create!(offer: o, name:"John")
ActiveRecord::RecordInvalid: Validation failed: Aba transit number can't be blank, Aba transit number has an invalid format, ...

但是,当我从嵌套表单尝试此操作时,对收件人进行的唯一验证是名称验证。我认为原因是 to_usd? returns false 因为报价尚未创建,所以没有 offer_id 或 offer_acceptance_id.

有没有办法让收件人模型知道记录正在由 currency_to 设置为 "usd" 的报价保存?即,在嵌套形式创建时,父属性是否可以传递给子模型?

我发现唯一需要做的就是在商品上添加关联#create 操作

@recipient = Recipient.new(offer_params[:recipient_attributes])
@recipient.offer = @offer