参考资料库
HTTP 状态码速查表
按成功、重定向、客户端错误和服务端错误分组的常见 HTTP 状态码。
OK
参考： Request succeeded.
200 OKMoved permanently
参考： Permanent redirect.
301 Moved PermanentlyNot found
参考： Resource does not exist at this URL.
404 Not FoundServer error
参考： Server failed unexpectedly.
500 Internal Server Error