#<User::ActiveRecord_Associations_CollectionProxy 的未定义方法“推荐”：

Question

我正在实施推荐系统 rails 5.1。我想推荐到第 8 代。我的隶属关系 class 如下：

class Affiliation < ApplicationRecord
  belongs_to :affiliate, :class_name => "User", :foreign_key => "affiliate_id"
  belongs_to :referred, :class_name => "User", :foreign_key => "referred_id"
     validates_presence_of :affiliate, :referred
     validates_uniqueness_of :referred_id
       private
        def validate
          errors.add_to_base("Affiliate and Referrer can't be the same 
        user.") if affiliate and (affiliate == referred)
        end
       end

我的User.rb

class User < ApplicationRecord
 has_many :affiliations, :foreign_key => "affiliate_id", :dependent => :destroy
   has_many :referrals, :through => :affiliations, :source => :referred
  # map.affiliate_referral 'a/:referrer_code', :controller => 
 'referrals', :action => 'new'
  def affiliate_link
    "https://localhost:3000/members/new/?referrer_code=#
    {self.affiliate_code}"
 end

现在推荐系统正在运行，我可以为他们的推荐人创建成员

挑战在于如何看待第 1 代到第 8 代。我收到此错误：

undefined method `referrals' for #<User::ActiveRecord_Associations_CollectionProxy:0x00007f48e4c2d2e0>

我可以推荐第一代，但从第二代开始就不行了。

请帮忙...？？？这是我的仪表板控制器

class DashboardController < ApplicationController
         def dashboard
                 # storage for referrals and affilations through eight 
         generations

           #generate first generation referrals
             def flatten_scopes(scopes)
            scopes.inject([]) { |a,r| r.is_a?(Array) ? a += flatten_scopes(r) : a.push(r) }
   end

       @firstgeners = referral_gen(current_user)
       @secondgeners ||= []
       @thirdgeners ||= []
       @fourthgeners ||= []
      @fifthgeners ||= []
      @sixthgeners ||= []
     @seventhgeners ||= []
     @eightgeners ||= []
            #loop first generation referrals to get the affiliates to 
         form our second 
        generation affiliations 
        #@firstgeners = @firstgeners1.flatten

        #@secondgeners1 = []
               @firstgeners = flatten_scopes(@firstgeners)
             if  @firstgeners.any?
            @firstgeners.each do |u| 
        if u.referrals.any?

           @secondgeners << u.referrals
           end
       end
        end

      #@secondgeners = @secondgeners1.flatten
      #from second generation referrals generate the affiliations 
      # @thirdgeners1 = []
      @secondgeners = flatten_scopes(@secondgeners)
      if @secondgeners.any?
      @secondgeners.each do |u| 
      if u.referrals.any?
     @thirdgeners << u.referrals
       end
     end
    end
    #@thirdgeners = @thirdgeners1.flatten

     @thirdgeners = flatten_scopes(@thirdgeners)
     #from third generation referrals generate the affiliations
    if @thirdgeners.any?
      @thirdgeners.each do |u| 
     if u.referrals.any?
      @fourthgeners << u.referrals
    end
    end
    end 
    #@fourthgeners = @fourthgeners1.flatten



      #from third generation referrals generate the affiliations
        @fourthgeners = flatten_scopes(@fourthgeners)
        if @fourthgeners.any?
       @fourthgeners.each do |u| 
       if u.referrals.any?
       @fifthgeners << u.referrals
       end
       end
       end 
    # @fifthgeners = @fifthgeners1.flatten

     @fifthgeners = flatten_scopes(@fifthgeners)
     if @fifthgeners.any?
        @fifthgeners.each do |u| 
         if u.referrals.any?
           @sixthgeners << u.referrals
          end
          end
          end

       #  @sixthgeners = @sixthgeners1.flatten 
        @sixthgeners = flatten_scopes(@sixthgeners)
         if @sixthgeners.any?
          @sixthgeners.each do |u| 
          if u.referrals.any?
          @seventhgeners << u.referrals
          end
         end
         end
         #@seventhgeners = @seventhgeners.flatten

        @secondgeners = flatten_scopes(@seventhgeners)
         if @seventhgeners.any?
           @seventhgeners.each do |u| 
           if u.referrals.any?
            @eightgeners << u.referrals
           end
          end
           end 

         #@eightgeners = @eightgeners1.flatten
         end

         #generate all affiliations  of current_user

               def referral_gen(user)
                 referrals = user.referrals
                 return referrals
               end

Answer 1

错误来自仪表板控制器这一行

                  if u.referrals.any?
                  @thirdgeners << u.referrals

这条线在下面的区块内..一旦我的第一代推荐人推荐了其他人。发生错误。如果他们没有，它运作良好。只是打电话给我的推荐人就可以了，因为我有这样的活动记录协会。但我认为 current_user.referrals 会给我用户数组。我可以遍历他们并获得他们的推荐，就像 user.referrals 一样重复 8 次。但不是那样工作的。

 @secondgeners = flatten_scopes(@secondgeners)
       if @secondgeners.any?
           @secondgeners.each do |u| 
           if u.referrals.any?
              @thirdgeners << u.referrals
         end
         end
        end

Answer 2

现在我开始工作了。完整的用户对象仅在第一次调用集合 @user.referrals 时可用，在此级别之后，之前的调用无法获得此用户所推荐的用户组的唯一关联。所以我做了这样的事情：我使用数据库中的推荐代码进行搜索并 return 正确的推荐。即使性能缓慢，它也可以向上工作到第 8 代。

if @firstgeners.any?
  @firstgeners.each do |u|
  @users.each do |e|
    if e.referrer_code == u.affiliate_code
      @secondgeners.push(e)
    end
  end
end
end

#<User::ActiveRecord_Associations_CollectionProxy 的未定义方法“推荐”：

undefined method `referrals' for #<User::ActiveRecord_Associations_CollectionProxy:

ruby

ruby-on-rails

ruby-on-rails-5.1