def get_current_release(self):
        """Get the release ID of the "current" deployment, None if
        there is no current deployment.

        This method performs one network operation.

        :return: Get the current release ID
        :rtype: str
        """
        current = self._runner.run("readlink '{0}'".format(self._current))
        if current.failed:
            return None
        return os.path.basename(current.strip())