CanCan(Can) and Activeadmin: Index on nested relations

Question

I am using CanCan(Can) together with ActiveAdmin. However, I am seriously struggling to get CanCan(Can) to work properly on index for a “has_many through” relationship.

Basically my Invoice model looks like this

class Invoice < ActiveRecord::Base

  belongs_to :order
  belongs_to :country
  belongs_to :currency

  has_one :user, :through => :order
(…)

My order model like this

class Order < ActiveRecord::Base

  belongs_to :user
  belongs_to :product

  has_many :invoices

And my user model like this

class User < ActiveRecord::Base

  has_many :orders
  has_many :invoices, :through => :orders

My abilities are defined like this

can :read, Invoice, :user => adminuser.user

This works fine on individual invoices. So the right user can see this URL :3000/admin/invoices/1 while other users will get a not authorized error.

However on the index listing it goes south completely. :3000/admin/invoices/ returns the error message

Mysql2::Error: Unknown column 'invoices.user_id' in 'where clause': SELECT COUNT(count_column) FROM (SELECT 1 AS count_column FROM invoices WHERE invoices.user_id = 2 LIMIT 30 OFFSET 0) subquery_for_count

Obviously this is completely wrong as CanCan(Can) is looking at the wrong table. How do I set ActiveAdmin and CanCan(Can) to use a “through” lookup for this relationship on index? I have tried adding

def authorize_access!
  load_and_authorize_resource :through => :order
end   

to the controller of “ActiveAdmin.register Invoice” but it made no difference.

Any suggestion would be greatly appreciated!

Answer 1

Try this: can :read, Invoice, :user => { :id => adminuser.user.id }