ruby - Rails : Find with deep Association -

i have models :

ad.rb

class ad < activerecord::base        belongs_to :seller, polymorphic: true    scope :published, -> { where(state: "published") }  end 

car.rb

class car < ad  end 

dealership.rb

class dealership < activerecord::base    belongs_to :agent   has_many :cars, as: :seller  end 

agent.rb

class agent < user    has_one :dealership, dependent: :destroy  end 

user.rb

class user < activerecord::base    has_many :ads, as: :seller   has_many :subscriptions    def has_valid_subscription?     !subscription.valid(self.id).blank?   end  end 

i know there's lot of polymorphism... try keep databases simple possible. clean model focus on problem.

i try ads has seller user valid subscription !

but there 2 levels of association between model... , can't !

can show me way ?

thank lot.

add seller_user association ad model

class ad < activerecord::base   belongs_to :seller, polymorphic: true   belongs_to :seller_user, :foreign_key => :seller_id, :class_name => "user", conditions: { ads: { seller_type: "user"}}   scope :published, -> { where(state: "published") } end 

now can do

ad.all.collect{|ad| ad.seller_user && ad.seller_user.has_valid_subscripion?} 

if need ads of user subscription, can do

ad.joins(:seller_user => :subscriptions)