Methods to restrict access to a URL based on login status.
Not specified. LOGIN_OPTIONAL is assumed.
Does not require that the user is signed in.
If the user is not signed in, the authFailAction is taken. In addition, if the user is not an administrator for the application, they are given an error message regardless of authFailAction. If the user is an administrator, the handler proceeds.
If the user has signed in, the handler proceeds normally. Otherwise, the authFailAction is taken.