Rails%203%20In%20Action

Assigning permissions
method, you must define another named route in your config/routes.rb file using the
put method:
put '/admin/users/:user_id/permissions',
:to => 'admin/permissions#update',
:as => :update_user_permissions
With this method, you define a new route for your application that will only respond
to PUT requests to this route. The :user_id inside the route is a variable and is passed
to the action as params[:user_id]. The controller and action are defined using the
:to symbol, and finally the method itself is given a name with the :as option.
Now when you run the feature again, this route method is defined, but the
permissions method isn’t:
And I follow "Permissions"
undefined local variable or method 'permissions' [...]
➥(ActionView::Template::Error)
Great! It seems like your page just requires this permissions helper method.
DEFINING A HELPER METHOD
Back in chapter 6, you defined a helper method called admins_only in Application-
Helper, which allowed you to show links only for admin users. This time, you define
the permissions method, which contains a list of permissions to display check boxes
on this page. Because this method is specific to views from the Admin ::Permissions-
Controller controller, place it in app/helpers/admin/permissions _helper.rb and
define it as shown in the following listing.
Listing 8.17 app/helpers/admin/permissions_helper.rb
module Admin::PermissionsHelper
def permissions
{
"view" => "View"
}
end
end
This permissions method returns a hash containing only one key-value pair at the
moment because you’re testing only one particular check box. You use this method to
display all the permissions you want to be configurable by admins, and you revisit this
method later to define more pairs. You use this method in your view twice; the first
time, you iterate over it like this:
When you iterate over a Hash object with the each method, the key for the hash
becomes the first block variable and the value becomes the second block variable;
these variables change for each key-value pair of the Hash object. In this case, it renders
headers for the table in this view. You use this helper later in the view too:
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