ruby-on-rails - 一个模型中相同类型的多个多态关系 - MongoID

Question

我不知道如何正确使用标题，所以让我解释一下。

我有我的课喜欢:

class Like
  include Mongoid::Document
  belongs_to :likable, polymorphic: true
  belongs_to :user
end

class Submission
  include Mongoid::Document

  belongs_to :creator, class_name: 'User', inverse_of: :submissions
  has_many :likes, :as => :likable, :dependent => :destroy
end

然后是导致问题的类:

class User
  include Mongoid::Document
  has_many :submissions, :dependent => :destroy

  has_many :liked_submissions, :as => :likable, :dependent => :destroy, class_name: 'Like'
  has_many :liked_comments, :as => :likable, :dependent => :destroy, class_name: 'Like'
end

现在，问题是我不知道如何在用户类中正确地同时拥有“喜欢的评论”和“喜欢的评论”。当我像上面那样得到它时，我收到错误:不明确的关系:liked_submissions，:liked_comments defined on User. 当试图为提交创建一个喜欢时。

我环顾四周，发现一个 Github issue 说这可能是不可能的，但我又找不到这个 issue，我什至不确定它是否与这个 issue 有关。

这是否可能，如果不可能，有什么绕过它的建议吗？我也想在 BlogPost 模型中使用点赞，但如果这不起作用，我将不得不寻找另一种方法。

提前致谢。

Answer 1

我试过了，它可以使用 mongoid 版本 4.0.2:

class Like
  include Mongoid::Document

  belongs_to :likable, polymorphic: true
  belongs_to :user, inverse_of: :user
end

class Submission
  include Mongoid::Document

  belongs_to :creator, class_name: 'User', inverse_of: :submissions
  has_many :likes, as: :likable, dependent: :destroy
end

class User
  include Mongoid::Document

  has_many :submissions, dependent: :destroy

  has_many :likes, as: :user
  has_many :liked_submissions, as: :likable, dependent: :destroy, class_name: 'Like'
  has_many :liked_comments, as: :likable, dependent: :destroy, class_name: 'Like'
end

class BlogPost
  include Mongoid::Document

  has_many :likes, as: :likable, dependent: :destroy
end

另外 user.liked_submissions 和 user.liked_comments 是相同的关系，所以它等同于声明这样的别名:

class User
  include Mongoid::Document

  has_many :submissions, dependent: :destroy

  has_many :likes, as: :user
  has_many :liked_submissions, as: :likable, dependent: :destroy, class_name: 'Like'

  alias :liked_comments :liked_submissions
end