对于proxy_owner在ActiveRecord的替代方法 [英] Alternative method for proxy_owner in ActiveRecord

问题描述

ActiveRecord的proxy_owner现在是很precated这里的解释很含糊如何去改变它，所以我不知道如何使用它我的情况：   http://apidock.com/rails/ActiveRecord/Associations/AssociationProxy

ActiveRecord proxy_owner is now deprecated and the explanation here is very vague on how to change it, so I'm not sure how to use it my case: http://apidock.com/rails/ActiveRecord/Associations/AssociationProxy

下面是我想要做什么：

class Library < ActiveRecord::Base
  has_many :books do
    def some_method
      proxy_owner.author
    end
  end
end

我得到一个警告，当我运行此$ C C的proxy_owner $是pcated德$ P $：

I get a warning when I run this code that proxy_owner is deprecated:

DEPRECATION WARNING: Calling record.books.proxy_owner is deprecated. Please use record.association(:books).owner instead.

我可以代替proxy_owner.author有：

I can replace proxy_owner.author with:

@associaton.owner.author

本作品;然而，似乎危险。我失去了一些东西呢？

This works; however, it seems dangerous. Am I missing something here?

推荐答案

我认为这是比较安全的发送：所有者到 proxy_association 来代替：

I think it's safer to send :owner to proxy_association instead:

class Library < ActiveRecord::Base
  has_many :books do
    def some_method
      proxy_association.owner.author
    end
  end
end

使用 proxy_association 目前在<一提到href="http://api.rubyonrails.org/classes/ActiveRecord/Associations/ClassMethods.html#label-Association+extensions">documentation:

不过，里面的实际扩展code，您将无法访问   记录（record.association（：项目）.owner）同上。在这种情况下，您可以访问proxy_association。   例如，record.association（：项）和   record.items.proxy_association将返回相同对象，允许   你做出像proxy_association.owner内部关联电话   扩展。

However, inside the actual extension code, you will not have access to the record (record.association(:items).owner) as above. In this case, you can access proxy_association. For example, record.association(:items) and record.items.proxy_association will return the same object, allowing you to make calls like proxy_association.owner inside association extensions.

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