Python中的logging模块是什么 logging模块如何配置日志记录

import logging

# 配置logging的基本设置
logging.basicConfig(level=logging.INFO, 
                    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')

# 创建一个logger实例
logger = logging.getLogger(__name__)

# 记录一些信息
logger.info('程序开始运行')

try:
    result = 10 / 0
except Exception as e:
    logger.error('发生异常', exc_info=True) # 记录异常信息

logger.info('程序运行结束')

logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s - %(levelname)s - %(filename)s:%(lineno)d - %(message)s')

import logging

# 创建一个logger
logger = logging.getLogger('my_app')
logger.setLevel(logging.DEBUG)

# 创建一个文件handler，并将日志级别设置为DEBUG
file_handler = logging.FileHandler('my_app.log')
file_handler.setLevel(logging.DEBUG)

# 创建一个formatter，并将其添加到handler
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
file_handler.setFormatter(formatter)

# 将handler添加到logger
logger.addHandler(file_handler)

# 现在你可以使用logger记录信息了
logger.debug('这是一个debug级别的消息')
logger.info('这是一个info级别的消息')

import logging

def setup_logger(name, log_file, level=logging.INFO):
    """To setup as many loggers as you want"""

    handler = logging.FileHandler(log_file)        
    formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
    handler.setFormatter(formatter)

    logger = logging.getLogger(name)
    logger.setLevel(level)
    logger.addHandler(handler)

    return logger

from logger_config import setup_logger

# 创建一个logger
logger = setup_logger('my_module', 'my_module.log')

# 使用logger记录信息
logger.info('模块开始运行')

import logging
import logging.handlers
import multiprocessing
import queue

def worker_process(queue):
    # 为每个进程配置一个logger
    logger = logging.getLogger('worker')
    handler = logging.handlers.QueueHandler(queue)  # 使用QueueHandler
    logger.addHandler(handler)
    logger.setLevel(logging.INFO)

    logger.info('Worker process started')
    logger.info('Worker process finished')

def listener_process(queue):
    # 配置listener的logger
    logger = logging.getLogger('listener')
    logger.setLevel(logging.DEBUG)

    # 创建一个FileHandler，将日志写入文件
    file_handler = logging.FileHandler('multiprocess.log')
    formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
    file_handler.setFormatter(formatter)

    # 创建一个QueueListener，监听队列并将消息传递给handler
    listener = logging.handlers.QueueListener(queue, file_handler)
    listener.start()

    logger.info('Listener process started')
    listener.info('Listener process finished')
    listener.stop()

if __name__ == '__main__':
    # 创建一个队列
    log_queue = queue.Queue(-1)

    # 启动listener进程
    listener = multiprocessing.Process(target=listener_process, args=(log_queue,))
    listener.start()

    # 启动worker进程
    workers = []
    for i in range(2):
        worker = multiprocessing.Process(target=worker_process, args=(log_queue,))
        workers.append(worker)
        worker.start()

    # 等待所有worker进程完成
    for worker in workers:
        worker.join()

    listener.join()

from flask import Flask, request
import logging

app = Flask(__name__)

# 配置logging
logging.basicConfig(level=logging.INFO, 
                    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')
logger = logging.getLogger(__name__)

@app.route('/log_level', methods=['POST'])
def set_log_level():
    level = request.form.get('level', 'INFO').upper()
    try:
        log_level = getattr(logging, level)
        logger.setLevel(log_level)
        return f"Log level set to {level}", 200
    except AttributeError:
        return "Invalid log level", 400

if __name__ == '__main__':
    app.run(debug=True)