Authenicated user is null in singleton

[John5]

I am trying to create a /Me singleton endpoint which displays some information about the user who is currently authenticated. I have already added authentication middleware. When I am not authenticated I get an error message like expected. When I am authenticated I get a response. However, when I try to access \Auth::user() from within the LodataServiceProvider class it always returns null while I would expect an instance of the User model. The documentation for singletons is very limited, an example on how to show information about the current user would be a good addition there, as it is the most common use for a singleton.

Stripped down version of my code that always returns null values for all properties:

class LodataServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        \Lodata::add($this->meSingleton());
    }

    protected function meSingleton(): Singleton
    {
        $user = \Auth::user();
        $entity = new EntityType('Users');
        $entity->addDeclaredProperty(User::EMAIL, Type::string());
        $entity->addDeclaredProperty(User::FIRST_NAME, Type::string());
        $entity->addDeclaredProperty(User::LAST_NAME, Type::string());
        $singleton = new Singleton('Me', $entity);
        if ($user instanceof User) {
            $singleton[User::EMAIL] = $user->email;
            $singleton[User::FIRST_NAME] = $user->getFirstName();
            $singleton[User::LAST_NAME] = $user->getLastName();
        }
        return $singleton;
    }
}