嵌套有许多通过插件和命名范围

Question

我有一个用户模型（：名称，：密码，：电子邮件），事件模型（：名称，：等）和兴趣模型（：名称）[＆gt;所有单数＆lt;]

然后我创建了两个连接表 -＆gt;用户兴趣和事件兴趣；每个不包含主键，仅分别由 user_id/interest_id 和 event_id/interest_id 组成。 [>plural<]

我的模型使用 Nested Has Many Through 插件

user.rb => has_many :users_interests
 has_many :interests, :through => :users_interests
 has_many :events_interests, :through => :interests
 has_many :events, :through => :events_interests

event.rb => has_many :events_interests
  has_many :interests, :through => :events_interests
     has_many :users_interests, :through => :interests
  has_many :users, :through => :users_interests

interest.rb => has_and_belongs_to_many :users
               has_and_belongs_to_many :events

events_interests.rb => belongs_to :interests
                    belongs_to :events
users_interests.rb => belongs_to :users
                   belongs_to :interests

唷..ok 所以我想要创建一个命名范围，查找与特定用户共享兴趣的所有事件。这是有人帮助我的一些代码。

named_scope :shares_interest_with_users, lambda {|user|
{ :joins => :users_interests,
  :conditions => {:users_interests => {:user_id => user}}
   }}

当我从控制器运行时 =>

@user = User.find(1) 
@events = Event.shares_interest_with_user(@user)

我收到错误：

uninitialized constant Event::EventsInterest

任何人都可以看到我搞砸了什么吗？

Answer 1

你一定是一路上命名错了。乍一看，我会说你有一个文件或类命名不正确。请记住，模型名称必须始终是单数，无论是在文件名还是类名中，否则 Rails 将无法建立连接。问题的另一个根源是belongs_to 的参数也必须是单数。即使您做对了，当您运行命名范围时，HABTM 与用户的利益关系也会引发错误。

我能够使用以下模型解决您的错误。

user.rb

class User < ActiveRecord::Base
has_many :users_interests
  has_many :interests, :through => :users_interests
  has_many :events_interests, :through => :interests
  has_many :events, :through => :events_interests
end

users_interest.rb

class UsersInterest < ActiveRecord::Base
  belongs_to :user
  belongs_to :interest
end

interest.rb

class Interest < ActiveRecord::Base 
  has_many :users,:through => :users_interests
  has_many :users_interests
  has_many :events_interests
  has_many :events, :through => :events_interests
end

**events_interest.rb

class EventsInterest <ActiveRecord::Base
  belongs_to :interest
  belongs_to :event
end

event.rb

class Event <ActiveRecord::Base 
  has_many :events_interests
  has_many :interests, :through => :events_interests
  has_many :users_interests, :through => :interests
  has_many :users, :through => :users_interests


  named_scope :shares_interest_with_users, lambda {|user|
    { :joins => :users_interests,
      :conditions => {:users_interests => {:user_id => user}}
    }
  }

end