Kivy Logger在PYTHON模式下将Python异常识别为警告的问题求助

问题原因 #

当设置Logger.mode = "PYTHON"时，Kivy的Logger会捕获标准错误流（stderr）的输出，并默认以WARNING级别记录。未被捕获的Python异常会输出到stderr，因此被Kivy Logger拦截后标记为WARNING，即使程序已经终止。

解决方案 #

方案1：修改Kivy Logger的stderr日志级别 #

直接调整Kivy Logger中stderr logger的级别，将其从WARNING改为ERROR：

import logging
logging.basicConfig(
    filename = "log.log",
    filemode = "w",
    encoding = "utf-8",
    force = True,
    level = logging.INFO,
    format = "%(asctime)s %(levelname)-8s %(message)s",
    datefmt = "%Y-%m-%d %H:%M:%S"
)

from kivy.logger import Logger, LOG_LEVELS
Logger.mode = "PYTHON"
# 修改stderr logger的级别为ERROR
Logger.setLevel('stderr', LOG_LEVELS['error'])

方案2：用Python logging接管未处理异常 #

通过Python logging模块结合sys.excepthook接管未捕获异常的处理，确保异常以ERROR级别记录，同时避免被Kivy Logger以WARNING捕获：

import logging
import sys

def handle_uncaught_exception(exc_type, exc_value, exc_traceback):
    if issubclass(exc_type, KeyboardInterrupt):
        # 保留键盘中断的默认处理逻辑
        sys.__excepthook__(exc_type, exc_value, exc_traceback)
        return
    # 以ERROR级别记录完整异常信息
    logging.error("未捕获的异常", exc_info=(exc_type, exc_value, exc_traceback))

sys.excepthook = handle_uncaught_exception

logging.basicConfig(
    filename = "log.log",
    filemode = "w",
    encoding = "utf-8",
    force = True,
    level = logging.INFO,
    format = "%(asctime)s %(levelname)-8s %(message)s",
    datefmt = "%Y-%m-%d %H:%M:%S"
)

from kivy.logger import Logger
Logger.mode = "PYTHON"

配置后，未捕获的异常会直接通过Python logging以ERROR级别写入日志，不会被Kivy Logger转为WARNING。

方案3：禁用Kivy对stderr的捕获 #

如果不需要Kivy处理stderr输出，可以直接关闭该功能，但需结合方案2才能将异常记录到日志文件：

import logging
import sys

def handle_uncaught_exception(exc_type, exc_value, exc_traceback):
    if issubclass(exc_type, KeyboardInterrupt):
        sys.__excepthook__(exc_type, exc_value, exc_traceback)
        return
    logging.error("未捕获的异常", exc_info=(exc_type, exc_value, exc_traceback))

sys.excepthook = handle_uncaught_exception

logging.basicConfig(
    filename = "log.log",
    filemode = "w",
    encoding = "utf-8",
    force = True,
    level = logging.INFO,
    format = "%(asctime)s %(levelname)-8s %(message)s",
    datefmt = "%Y-%m-%d %H:%M:%S"
)

from kivy.logger import Logger
Logger.mode = "PYTHON"
# 关闭Kivy对stderr的捕获
Logger.stderr = False

内容的提问来源于stack exchange，提问作者Abel Gutiérrez