__init__.py 文件源码

def get_unsupported_upper_protocol():
    """
    This is used to determine the highest protocol version that is NOT
    supported by the version of C* running
    """

    if Version(CASSANDRA_VERSION) >= Version('2.2'):
        return None
    if Version(CASSANDRA_VERSION) >= Version('2.1'):
        return 4
    elif Version(CASSANDRA_VERSION) >= Version('2.0'):
        return 3
    else:
        return None