How to redirect an unauthorized user to a specific page?

Question

Django

Hello! Please help me figure it out and point me to the right path.
How to redirect an unauthorized user to a specific page?
For example, an unauthorized user visits /admin/ , you need to redirect this user to /admin/login/ . In cases where he is authorized, he calmly goes to the address /admin/ .
PS The task was to create my own admin panel without using the one that is out of the box in Django. Below, I created a custom form for the login page, which inherits from AuthenticationForm.
URLs.py:

urlpatterns = [
    # Admin Dashboard
    url(r'^admin/$', DashboardView.as_view()),

    # Admin Login
    url(r'^admin/login/$',
        authentication_views.login,
        {
            'template_name': 'administration/login.html',
            'authentication_form': AdminAuthenticationForm
        },
        name='login'),
]

forms.py:

class AdminAuthenticationForm(AuthenticationForm):
    """
        A custom authentication form used in the administration app.
    """
    error_messages = {
        'invalid_login': ("Ошибка! Проверьте ваш Логин или Пароль администратора еще раз."),
    }
    required_css_class = 'required'

    def confirm_login_allowed(self, user):
        if not user.is_active or not user.is_staff:
            raise forms.ValidationError(
                self.error_messages['invalid_login'],
                code='invalid_login',
                params={'username': self.username_field.verbose_name}
            )

Answer 1

Simply mark the desired view with the @login_required decorator and either specify the login_url in the decorator's parameters, or specify the LOGIN_URL parameter in the settings .