Rails strong parameters incremental addition

Question

Does anyone know, if with strong_parameters gem, we can incrementally add attributes like below:

def user_params
  params[:user].permit(:name, :email)

  if current_user.admin?
    params[:user].permit(:is_admin)
  end
end

Here I am incrementally asking the code to permit :is_admin parameter if the current user is an admin. Shouldn't it just add to the previously permitted list of parameters (:name and :email)?

Answer 1

They way I have done it is to put all my params in a class Like the strong-parameters railscast..

this way I have something like this

 class PermittedParams < Struct.new(:params,:admin)

   def administrator_attributes
       allowed = [:email, :name, :password, :password_confirmation, :password_digest]
    if admin.has_any_role? :realm_admin, :system_admin
      allowed << :active << :roles
    end
    allowed
   end

   .... other models .... 



   def method_missing(method,*args,&block)
    attributes_name = method.to_s + '_attributes'
    if respond_to? attributes_name, false
      params.require(method).send(:permit, *method(attributes_name).call)
    else
      super
    end
  end
 end

then in the controller just call @administrator.update_attributes(permitted_params.administrator)

as it is just an array you can build up the array, and then just use * to pass it into the permit.