checkers.py 文件源码

def requestAvatarId(credentials):
        """
        @param credentials: something which implements one of the interfaces in
        self.credentialInterfaces.

        @return: a Deferred which will fire a string which identifies an
        avatar, an empty tuple to specify an authenticated anonymous user
        (provided as checkers.ANONYMOUS) or fire a Failure(UnauthorizedLogin).
        Alternatively, return the result itself.
        """

# A note on anonymity - We do not want None as the value for anonymous
# because it is too easy to accidentally return it.  We do not want the
# empty string, because it is too easy to mistype a password file.  For
# example, an .htpasswd file may contain the lines: ['hello:asdf',
# 'world:asdf', 'goodbye', ':world'].  This misconfiguration will have an
# ill effect in any case, but accidentally granting anonymous access is a
# worse failure mode than simply granting access to an untypeable
# username.  We do not want an instance of 'object', because that would
# create potential problems with persistence.