Rails association with multiple foreign keys

Question

I want to be able to use two columns on one table to define a relationship. So using a task app as an example.

Attempt 1:

class Use         


        

Answer 1

I worked out a solution for this. I'm open to any pointers on how I can make this better.

class User < ActiveRecord::Base

  def tasks
    Task.by_person(self.id)
  end 
end

class Task < ActiveRecord::Base

  scope :completed, -> { where(completed: true) }   

  belongs_to :owner, class_name: "User", foreign_key: "owner_id"
  belongs_to :assignee, class_name: "User", foreign_key: "assignee_id"

  def self.by_person(user_id)
    where("owner_id = :person_id OR assignee_id = :person_id", person_id: user_id)
  end 
end

This basically overrides the has_many association but still returns the ActiveRecord::Relation object I was looking for.

So now I can do something like this:

User.first.tasks.completed and the result is all completed task owned or assigned to the first user.