Fully-qualified name of this variable.

        Example:
        ``projects/my-project/configs/my-config``

        :rtype: str
        :returns: The full name based on project and config names.

        :raises: :class:`ValueError` if the config is missing a name.

def full_name(self):
        """Fully-qualified name of this variable.

        Example:
        ``projects/my-project/configs/my-config``

        :rtype: str
        :returns: The full name based on project and config names.

        :raises: :class:`ValueError` if the config is missing a name.
        """
        if not self.name:
            raise ValueError("Missing config name.")
        return "projects/%s/configs/%s" % (self._client.project, self.name)