Question

我有这个模特：

class Vote
  include Mongoid::Document
  include Mongoid::Timestamps

  field :vote, :type=>Integer

  embedded_in :voteable, :inverse_of => :votes
  referenced_in :user

  attr_accessible :vote, :user, :voteable

  validates :vote,:inclusion => [-1, 1]
  validates :user ,:presence=> true,:uniqueness=>true

end

问题是每次投票的用户唯一性验证不起作用，同一个用户可以创建多个投票，这不是我想要的。任何想法如何解决？

Answer 1

看起来这是一个已知问题。

http://groups.google.com/group/mongoid/browse_thread/thread/e319b50d87327292/14ab7fe39337418a?lnk=gst&q=validates#14ab7fe39337418a

https://github.com/mongoid/mongoid/issuesearch?state=open&q=validates#issue/373

可以编写自定义验证来强制执行唯一性。这是一个快速测试：

class UserUniquenessValidator < ActiveModel::EachValidator
  def validate_each(record, attribute, value)
    record.errors[attribute] << "value #{value} is not unique" unless is_unique_within_votes(record, attribute, value)
  end

  def is_unique_within_votes(vote, attribute, value)
    vote.voteable.votes.each do |sibling|
      return false if sibling != vote && vote.user == sibling.user
    end
    true
  end
end

class Vote
  ...
  validates :user ,:presence => true, :user_uniqueness => true
end

Mongoid参考唯一性

1 个答案: