CanCan load_and_authorize_resource triggers Forbidden Attributes - ruby-on-rails

Question

I have a standard RESTful controller that uses strong parameters.
class UsersController < ApplicationController
respond_to :html, :js
def index
#users = User.all
end
def show
#user = User.find(params[:id])
end
def new
#user = User.new
end
def edit
#user = User.find(params[:id])
end
def create
#user = User.new(safe_params)
if #user.save
redirect_to #user, notice: t('users.controller.create.success')
else
render :new
end
end
def update
#user = User.find(params[:id])
if #user.update_attributes(safe_params)
redirect_to #user, notice: t('users.controller.update.success')
else
render :edit
end
end
def destroy
#user = User.find(params[:id])
if current_user != #user
#user.destroy
else
flash[:error] = t('users.controller.destroy.prevent_self_destroy')
end
redirect_to users_url
end
private
def safe_params
safe_attributes =
[
:first_name,
:last_name,
:email,
:password,
:password_confirmation,
]
if current_user.is?(:admin)
safe_attributes += [:role_ids]
end
params.require(:user).permit(*safe_attributes)
end
end
In my config/initializers I have the file strong_parameters.rb
ActiveRecord::Base.send(:include, ActiveModel::ForbiddenAttributesProtection)
When I add a simple call to CanCan's load_and_authorize_resource I get
1) UsersController POST create with invalid params re-renders the 'new' template
Failure/Error: post :create, user: #attr
ActiveModel::ForbiddenAttributes:
ActiveModel::ForbiddenAttributes
# ./spec/controllers/users_controller_spec.rb:128:in `block (4 levels) in <top (required)>'
Where #attr in the test is defined as
before(:each) do
#attr =
{
first_name: "John",
last_name: "Doe",
email: "user#example.com",
password: "foobar",
password_confirmation: "foobar"
}
end
In the tests I have it all setup properly to login the user and give them the necessary roles for being an administrator so I know it's not that. I don't know why this is causing ForbiddenAttributes to trigger. I'm sure it's something simple I've overlooked. Has anyone else encountered this problem and found a solution to it?

Answer 1

I believe this is because CanCan will use its own getter method for the requested resource if you don't pre-load it with a before_filter. So you could add this to the controller and it should work:
class UsersController < ApplicationController
before_filter :new_user, :only => [:new, :create]
load_and_authorize_resource
def new_user
#user = User.new(safe_params)
end
end
(And then do the same for the edit/update actions.)

Answer 2

before_filter do
params[:user] = safe_params
end
load_and_authorize_resource