Rails associations can't mass-assign foreign key

Question

Maybe I am doing it wrong but here is my issue:

@restaurant = current_user.restaurants.build(params[:restaurant])

This builds a new restaurant object where the user_id is set to the current_user.id. This only works if you set attr_accessible :user_id in the Restaurant Model. If not you get a

ActiveModel::MassAssignmentSecurity::Error: Can't mass-assign protected attributes:
user_id

What I want is to have the user_id defined via .build but at the same time I do not want the attr_accessible :user_id because then it is possible for someone to set the user_id of this record to some other user's id, which would be bad!!

I thought the foreign keys were excluded from this Mass Assignment Security and were enforced if you create a new object via the association .build or .create methods.

Any suggestions? I dont want to go back to

@restaurant = current_user.restaurants.build(params[:restaurant])
@restaurant.user = current_user

because that kind of defeats the purpose of .build

Answer 1

Are you using Rails 3.2.0.rc1? That's a know bug github.com/rails/rails/issues/4051 (resolved)