为什么我的 ActiveRecord 模型没有调用 before_save？

Question

当我使用 IRB 创建新模型实例并保存时，控制台没有任何内容打印出来，并且我收到“ActiveRecord::StatementInvalid: Mysql::Error: Column 'user_id' cannot be null”错误，所以我假设before_save 没有被调用。我不知道为什么。我什至尝试过使用 before_save 过滤器。这是我的代码：

require 'secure_resource/secure_resource_encryption'

class Database < ActiveRecord::Base
  belongs_to :username_encryption, :class_name => "Encryption", :foreign_key => :username_encryption_id
  belongs_to :password_encryption, :class_name => "Encryption", :foreign_key => :password_encryption_id

  # Virtual attribute to retrieve the decrypted username.
  def username
    if self.username_encryption.nil?
      return nil
    end

    begin
      return self.username_encryption.encryption
    rescue SecureResourceError
      raise SecureResourceError
    end
  end

  # Provides a way to reset the username.
  def username=(username)
    if self.username_encryption.nil?
      self.username_encryption = Encryption.new
      self.username_encryption.encryption = username
    end
  end

  # Virtual attribute to retrieve the decrypted password.
  def password
    if password_encryption.nil?
      return nil
    end

    begin
      return password_encryption.encryption
    rescue SecureResourceError
      raise SecureResourceError
    end
  end

  # Provides a way to reset the password.
  def password=(password)
    if self.password_encryption.nil?
      self.password_encryption = Encryption.new
      self.password_encryption.encryption = password
    end
  end

  def before_save
    p 'ZZZZZZZZZZZZZZZ'
    p self.user_id.to_s + ' ZZZZZZ'
    p 'ZZZZZZZZZZZZZZZ'
    self.username_encryption.user_id = self.user_id
    self.username_encryption.save
    self.username_encryption_id = self.username_encryption.id

    self.password_encryption.user_id = self.user_id
    self.password_encryption.save
    self.password_encryption_id = self.password_encryption.id
  end
end

Answer 1

如您所见，in the documentation、before_save 发生在 验证之后。在您的情况下，验证将失败，并且永远不会调用 before_save。

由于您的回调目标是在验证发生之前将您的对象设置为有效状态，因此请尝试 before_validation 回调。