Rails: ActiveRecord::HasManyThroughSourceAssociationNotFoundError: Could not find the source association(s)

Question

I have the following code (somewhat simplified ...

create_table :signatures do |t|
  t.integer :signer_id
  t.integer :card_id

  t.timestamps
end
         


        

Answer 1

User should be defined like this:

class User < ActiveRecord::Base

  has_many :sent_cards, :class_name => "Card", :foreign_key => "sender_id"
  has_many :received_cards, :class_name => "Card", :foreign_key => "recipient_id"

  has_many :signatures
  has_many :signed_cards, :through => :signatures, :source => :card

end

When your association name is different than the name used at the :through you have to define the source parameter. If you look at the exception message it explicitly asks you to do it.