Question

I have the following models:

class Publication < ActiveRecord::Base
  has_many :reviews
  has_many :users, :through => :owned_publications
  has_many :owned_publications
end

class User < ActiveRecord::Base
  has_many :publications, :through => :owned_publications
  has_many :owned_publications
end

class OwnedPublication < ActiveRecord::Base
  belongs_to :publication
  belongs_to :user
  has_one :review, :conditions => "user_id = #{self.user.id} AND publication_id = #{self.publication.id}"
end

In the third model, I’m trying to set a condition with a pair of variables. It seems like the syntax works, except that self is not an instance of OwnedPublication. Is it possible to get the current instance of OwnedPublication and place it into a condition?

Answer 1

I think your best bet is to just have the Review record belong_to an OwnedPublication, and setup your Publication model to get the reviews via a method:

def reviews
  review_objects = [] 
  owned_publications.each do |op|
    review_objects << op
  end
  review_objects
end

Might be a more efficient way if you use a subquery to get the information, but it removes the concept of having unnecessary associations.