Python日志记录：自定义记录器无输出

Question

使用教程：https://realpython.com/python-logging/， 我有以下脚本，仅包含：

import logging

# Create a custom logger
logger = logging.getLogger(__name__)

# Create handlers
c_handler = logging.StreamHandler()
f_handler = logging.FileHandler('file.log')
c_handler.setLevel(logging.INFO)
f_handler.setLevel(logging.DEBUG)

# Create formatters and add it to handlers
c_format = logging.Formatter('%(name)s - %(levelname)s - %(message)s')
f_format = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
c_handler.setFormatter(c_format)
f_handler.setFormatter(f_format)

# Add handlers to the logger
logger.addHandler(c_handler)
logger.addHandler(f_handler)

logger.debug('I am a debug msg')
logger.info('I am an info msg')

应同时将字符串写入控制台和文件（“ file.log”）。 文件已创建，bot没有内容。而且也没有输出到控制台。 有什么想法可能导致这种情况，或者缺少什么？

Answer 1

您忘记为记录器本身设置详细级别：

import logging

# Create a custom logger
logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG) # The logger still needs its verbose level

# Create handlers
c_handler = logging.StreamHandler()
f_handler = logging.FileHandler('file.log')
c_handler.setLevel(logging.INFO)
f_handler.setLevel(logging.DEBUG)

# Create formatters and add it to handlers
c_format = logging.Formatter('%(name)s - %(levelname)s - %(message)s')
f_format = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
c_handler.setFormatter(c_format)
f_handler.setFormatter(f_format)

# Add handlers to the logger
logger.addHandler(c_handler)
logger.addHandler(f_handler)

logger.debug('I am a debug msg')
logger.info('I am an info msg')

我也建议您针对每个处理程序而不是类似的语法阻止代码：

import logging

# Create a custom logger
logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)

# Streaming Handler
c_handler = logging.StreamHandler()
c_handler.setLevel(logging.INFO)
c_format = logging.Formatter('%(name)s - %(levelname)s - %(message)s')
c_handler.setFormatter(c_format)
logger.addHandler(c_handler)

# File Handler
f_handler = logging.FileHandler('file.log')
f_handler.setLevel(logging.DEBUG)
f_format = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
f_handler.setFormatter(f_format)
logger.addHandler(f_handler)

logger.debug('I am a debug msg')
logger.info('I am an info msg')