如何屏蔽gevent Flask/WSGI HTTP服务器接HTTPS请求的无效HTTP方法错误日志

当用户误将HTTPS请求发送到基于gevent运行的纯HTTP Flask服务器时，会生成一条无法通过常规Python异常捕获消除的乱码日志，推测该异常未进入Python代码执行层面。

代码示例 #

from flask import Flask
from gevent.pywsgi import WSGIServer

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "Hello, World!"

if __name__ == "__main__":
    http_server = WSGIServer(("0.0.0.0", 8000), app)
    http_server.serve_forever()

触发命令 #

curl https://localhost:8000

需消除的日志输出 #

<gevent._socket3.socket at 0x10272dbe0 object, fd=9, family=2, type=1, proto=0>: (from ('127.0.0.1', 63996)) Invalid HTTP method: "\x16\x03\x01\x01:\x01\x00\x016\x03\x035o;OÀ|¶\x9aã[3F\x81>?ÞB1f'ø×ÈùG\x0eAV\x9c\x1cÿ\x9f I+Hýò¶\x9aݽL\r{p\n"
{p" 400 - 0.0005314-05-17 08:09:57] ":65o;OÀ|¶ã[3F>?ÞB1f'ø×ÈùGAVÿò¶Ý½L

方法一：消除目标日志 #

gevent的WSGIServer通过内置的WSGIHandler处理请求日志，我们可以自定义handler并重写log_error方法，过滤掉HTTPS请求导致的无效方法日志：

from flask import Flask
from gevent.pywsgi import WSGIServer, WSGIHandler

class CustomWSGIHandler(WSGIHandler):
    def log_error(self, format, *args):
        # 过滤HTTPS握手数据导致的无效HTTP方法日志
        if format == "%s: (from %s) Invalid HTTP method: %r" and len(args) == 3:
            method = args[2]
            # HTTPS握手数据以\x16开头（SSL/TLS握手记录标识）
            if method.startswith('\x16'):
                return
        # 其他正常日志保持原有输出逻辑
        super().log_error(format, *args)

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "Hello, World!"

if __name__ == "__main__":
    http_server = WSGIServer(("0.0.0.0", 8000), app, handler_class=CustomWSGIHandler)
    http_server.serve_forever()

方法二：添加上下文说明日志 #

若需要保留提示性日志而非完全消除，可在自定义handler中替换原有乱码日志为友好的上下文提示：

from flask import Flask
from gevent.pywsgi import WSGIServer, WSGIHandler
import logging

# 配置基础日志格式
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
logger = logging.getLogger(__name__)

class CustomWSGIHandler(WSGIHandler):
    def log_error(self, format, *args):
        if format == "%s: (from %s) Invalid HTTP method: %r" and len(args) == 3:
            method = args[2]
            client_addr = args[1]
            if method.startswith('\x16'):
                # 输出带上下文的友好提示日志
                logger.warning(f"收到来自{client_addr}的HTTPS请求，但当前服务器仅支持HTTP协议，请检查请求配置")
                return
        super().log_error(format, *args)

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "Hello, World!"

if __name__ == "__main__":
    http_server = WSGIServer(("0.0.0.0", 8000), app, handler_class=CustomWSGIHandler)
    http_server.serve_forever()

内容的提问来源于stack exchange，提问作者Cyberwiz