Question

我遇到了Rails＆＃39; Validator＆＃39; 我有一个表FollowingRelationship来存储几个用户，我应该在其中验证follower_id != followed_id（用户无法自己跟踪）。

这是我的模特：

class FollowingRelationship < ApplicationRecord

  belongs_to :followed, class_name: "User"
  belongs_to :follower, class_name: "User"

  validates :follower_id, presence: true
  validates :followed_id, presence: true, followed_id: true
  validates_uniqueness_of :follower_id, scope: :followed_id 

  class FollowedValidator < ActiveModel::EachValidator

    def validate_each(record, attribute, value)
      record.errors.add attribute, "User can't follow itselves" unless record.follower_id != value
    end
  end
end

但验证器仍无法正常工作

FollowingRelationship.create(:follower_id => 1, :followed_id => 1)不应该创建记录，但它有效。

有人能帮帮我吗？感谢。

Answer 1

构建自定义验证器类对于单个方法验证来说有点多（除非需要在多个模型中使用）。试试这个

class FollowingRelationship < ApplicationRecord

  belongs_to :followed, class_name: "User"
  belongs_to :follower, class_name: "User"

  validates :follower_id, presence: true
  validates :followed_id, presence: true, followed_id: true
  validates_uniqueness_of :follower_id, scope: :followed_id
  validate  :does_not_follow_self

  def does_not_follow_self
    self.errors.add attribute, "User can't follow itself" unless self.follower != self.followed
  end
end

Answer 2

我为我的facebook克隆做了这样的验证器。

你可以找到它here。

基本版本看起来像这样

    def stop_friending_yourself
        errors.add(:user_id, "can't friend themself") if user_id == friend_id
    end

Rails

2 个答案: