5×× 服务器错误

501 Not Implemented 未实施

服务器不支持完成请求所需的功能.

当服务器无法识别请求方法并且无法支持任何资源时，这是适当的响应.

默认情况下，501 响应是可缓存的；即，除非方法定义或显式缓存控制¹另有说明.

• ¹ Calculating Heuristic Freshness RFC7234 Section 4.2.2
• Source: RFC7231 Section 6.6.2

501 代码参考

Rails HTTP Status Symbol :not_implemented

Go HTTP Status Constant http.StatusNotImplemented

Symfony HTTP Status Constant Response::HTTP_NOT_IMPLEMENTED

Python2 HTTP Status Constant httplib.NOT_IMPLEMENTED

Python3+ HTTP Status Constant http.client.NOT_IMPLEMENTED

Python3.5+ HTTP Status Constant http.HTTPStatus.NOT_IMPLEMENTED