How do you model “Likes” in rails?

Question

I have 3 models: User, Object, Likes

Currently, I have the model: a user has many Objects. How do I go about modeling:

1) A user can like many objects

2

Answer 1

You are close; to use a :through, relation, you first must set up the relationship you're going through:

class User < ActiveRecord::Base
  has_many :likes
  has_many :objects, :through => :likes
end

class Likes < ActiveRecord::Base
  belongs_to :user
  belongs_to :object
end

class Objects < ActiveRecord::Base
  has_many :likes
  has_many :users, :through => :likes    
end

Note that Objects should has_many :likes, so that the foreign key is in the right place. (Also, you should probably use the singular form Like and Object for your models.)