Rails%203%20In%20Action

Assigning permissions
class Admin::PermissionsController < Admin::BaseController
before_filter :find_user
end
Listing 8.15 app/controllers/admin/permissions_controller.rb
def index
@ability = Ability.new(@user)
@projects = Project.all
end
private
def find_user
@user = User.find(params[:user_id])
end
The new Ability instance created here lets you check the user’s ability to perform
specific actions on any project by simply calling this code:
@ability.can?(:"view", @project)
This syntax may look similar to the syntax used in TicketsController—it is. In that
controller, you used the cannot? method, which is the opposite of the can? method.
These methods are added to the controller by CanCan and are just shorter helper
methods to do almost exactly what you did in this controller. The only difference is
that you’re not acting on the current_user here, so you must define an Ability
object yourself and use that instead.
THE PERMISSIONS SCREEN
Now that you have the index action up, you need to make its view look like what is
shown in figure 8.5. Create a new file at app/views/admin/permissions/index.html.erb,
and fill it with the content from the following listing.
Figure 8.5 The permissions screen
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