Create a full (scheme included) hostname from the argument given.

        Only HTTP and HTTP+SSL protocols are allowed.

        Args:
            hostname: The hostname to use.
        Returns:
            The full hostname.
        Raises:
            ValueError: A not supported protocol is used.

def _construct_full_hostname(self, hostname):
        """Create a full (scheme included) hostname from the argument given.

        Only HTTP and HTTP+SSL protocols are allowed.

        Args:
            hostname: The hostname to use.
        Returns:
            The full hostname.
        Raises:
            ValueError: A not supported protocol is used.
        """
        if hostname.startswith(('http://', 'https://', )):
            return hostname
        if '://' in hostname:
            protocol, host = hostname.split('://', 1)
            raise ValueError('Protocol %s is not supported.' % protocol)
        return '://'.join([self.default_scheme, hostname, ])