ruby-on-rails – Rails 4：after_update回调导致无限循环

型号User.rb

after_update :check_phone

check_phone
  phone_validation if phone_changed?
end

def phone_validation
  code = Array.new(8){rand(36).to_s(36)}.join
  self.phone_verification_code = code
  self.save
end

然而,这导致无限循环.问题是在phone_validation方法中的self.save之后再次调用回调. phone_changed？显然仍然是真的.我该如何改变这种行为？

User.rb

attr_accessor  :phone_checked

after_update :check_phone, :unless => "phone_checked"

check_phone
  phone_validation if phone_changed?
end

def phone_validation
  code = Array.new(8){rand(36).to_s(36)}.join
  self.phone_verification_code = code
  self.phone_checked = true  # update flag
  self.save
end

要么

谨慎使用：skip callbacks

def phone_validation
 code = Array.new(8){rand(36).to_s(36)}.join
 self.update_column(:phone_verification_code => code)
end