如何禁用belongs_to的default_scope? [英] How to disable default_scope for a belongs_to?

问题描述

有没有办法为单个 belongs_to 关联禁用 default_scope?default_scope 适用于所有但我想绕过范围的单个 belongs_to.我对 with_exclusive_scope 很熟悉，但我认为它不能与belongs_to 一起使用.

Is there a way to disable the default_scope for a single belongs_to association? The default_scope is fine for all but a single belongs_to that I would like to bypass the scope. I'm familiar with with_exclusive_scope however I don't think that can be used with belongs_to.

有什么建议吗?

上下文:我试图在 acts_as_revisable 中允许 branch_source 关联指向不是最新的修订版(revisable_is_current 为假).

Context: I'm trying to allow the branch_source association in acts_as_revisable to point to a revision that is not the latest (revisable_is_current is false).

推荐答案

参加聚会可能有点晚(仅差 3 年)，但遇到了同样的问题，Tobias 的解决方案肯定是正确的方向，但它可以简化为 Rails 3.2+.我唯一仍然不喜欢的是 Document 的硬编码"类名，也许可以使用反射来变形...

Probably a bit late to the party (just short of 3 years), but just run into the same problem and the solution from Tobias is certainly the right direction, but it can be simplified for Rails 3.2+. The only thing I still don't like is the "hard coded" class name for Document, maybe it's possible to inflect using reflection...

无论如何这是我想出的:

Anyhow this is what I've come up with:

class Comment < ActiveRecord::Base
  # Document has some kind of default_scope
  belongs_to :document

  # Ensure document is not scoped, because Rails 3.2 uses modules it's
  # possible to use simple inheritance.
  def document
    Document.unscoped { super }
  end
end

更新:基于reflect_on_associationhttps://gist.github.com/2923336<获得了通用解决方案/a>

Update: got a generic solution, based on reflect_on_association https://gist.github.com/2923336

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