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Has_many inverse with polymorphism

I have an interesting dilemma, and I'm not sure if this Rails can even handle something or not, so naked with me ...

I have two models: users and projects. The idea is that users can keep track of both projects and other users. Naturally, users and projects are part of a polymorphic “follow-up” type. Now, using a custom model, I would like to get three things:

user.followed_users
user.followed_projects
user.followers

The first two are working fine; This is the third one I'm having problems with. This is a kind of reverse lookup when the foreign key becomes the “followable_id” column in the following table, but no matter how I model it, I cannot get the query to work correctly.

User model

has_many :follows, :dependent => :destroy
has_many :followed_projects, :through => :follows, :source => :followable, :source_type => "Project"
has_many :followed_users, :through => :follows, :source => :followable, :source_type => "User"
has_many :followers, :through => :follows, :as => :followable, :foreign_key => "followable", :source => :user, :class_name => "User"

Follow the model

class Follow < ActiveRecord::Base
  belongs_to :followable, :polymorphic => true
  belongs_to :user
end

:    followable_id  followable_type

, , :

SELECT `users`.* FROM `users` INNER JOIN `follows` ON `users`.`id` = `follows`.`user_id` WHERE `follows`.`user_id` = 7

"followable_id = 7 AND followable_type =" ", " user_id = 7 "

?

+5
2

. , - ( ), ( ).

    has_many    :follows,
                        :dependent => :destroy

    has_many    :followed_projects,
                        :through => :follows,
                        :source => :followable,
                        :source_type => "Project"

    has_many    :followed_users,
                        :through => :follows,
                        :source => :followable,
                        :source_type => "User"

    has_many    :reverse_follows,
                        :as => :followable,
                        :foreign_key => :followable_id,
                        :class_name => "Follow"

    has_many    :followers,
                        :through => :reverse_follows,
                        :source => :user

, !

+5

, . :

:foreign_key => "followable"

:

:foreign_key => "followable_id"

:

has_many :followers, :through => :follows, :as => :followable, :foreign_key => "followable_id", :source => :user, :class_name => "User"
0

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