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Python logging

最近在学习使用Python的logging组件，这个主键主要功能就是记录程序运行时产生的一些日志记录。

具体使用方法如下：

Set_Logging.py

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

import logging


class logging_config:
    @staticmethod
    def init_logging(logging_name):
        fh = logging.FileHandler(encoding='utf-8', mode='a', filename='/var/log/SMS_Receive_Service/IP_Filter.log', )
        # set up logging to file - see previous section for more details
        logging.basicConfig(handlers=[fh],
                            level=logging.DEBUG,
                            format='%(asctime)s %(name)-12s %(levelname)-8s %(message)s',
                            datefmt='%m-%d %H:%M')
        # define a Handler which writes INFO messages or higher to the sys.stderr
        console = logging.StreamHandler()
        console.setLevel(logging.INFO)
        # set a format which is simpler for console use
        formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s')
        # tell the handler to use this format
        console.setFormatter(formatter)
        # add the handler to the root logger
        logging.getLogger('').addHandler(console)

        # Now, we can log to the root logger, or any other logger. First the root...
        logging.info('日志记录已启动！')

        # Now, define a couple of other loggers which might represent areas in your
        # application:

        return logging.getLogger(logging_name)

首先这里设置文件记录日志的方式，日志最低的级别是DUBUG，设置了一些日志记录的格式已经文件编码。

之后定义了控制台Handler 处理器，默认消息级别为INFO，之后设置了显示消息的格式，之后将控制台Handler 处理器加入到root logger。

程序调用，返回一个logging。

具体调用方式：

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

from Set_Logging import logging_config


class IP_Filter:
    def __init__(self):
        # 设置日志记录
        logger_name = 'IP_Filter'
        self._logger_ip_filter = logging_config.init_logging(logger_name)


    def check_ip_as(self, ip, ip_context_info, redis_conn, mysql_conn):
        get_ip_as = ip_context_info['as']
        with closing(mysql_conn) as conn_mysql:
            with closing(conn_mysql.cursor()) as cur:
                # SQL 插入语句
                query_as_sql = "SELECT * FROM ip_as_num WHERE ip_as ='{}';".format(get_ip_as)
                # 执行SQL语句
                try:
                    cur.execute(query_as_sql)
                    # 获取所有记录列表
                    results = cur.rowcount
                except (MySQLdb.Error, MySQLdb.Warning) as e:
                    self._logger_ip_filter.error('执行as SQL命令查询的时候出现错误，具体错误内容： {error_message}'.format(error_message=e))
                    return False
                if results == 0:
                    return False
                else:
                    redis_conn.sadd('ip_as_black_list', ip)

由于日积月累导致单个日志文件很大，需要对日志文件进行切割，具体代码如下：

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

import logging
import logging.handlers


class logging_config:
    @staticmethod
    def init_logging(logging_name):
        fh = logging.handlers.TimedRotatingFileHandler("/var/log/SMS_Receive_Service/IP_Filter.log",
                                                       when='D',
                                                       interval=1,
                                                       backupCount=0)
        # fh = logging.FileHandler(encoding='utf-8', mode='a', filename='/var/log/SMS_Receive_Service/IP_Filter.log', )

        fh.suffix = "%Y%m%d-%H%M.log"
        # set up logging to file - see previous section for more details
        logging.basicConfig(handlers=[fh],
                            level=logging.DEBUG,
                            format='%(asctime)s %(name)-12s %(levelname)-8s %(message)s',
                            datefmt='%m-%d %H:%M')
        # define a Handler which writes INFO messages or higher to the sys.stderr
        console = logging.StreamHandler()
        console.setLevel(logging.INFO)
        # set a format which is simpler for console use
        formatter = logging.Formatter('%(name)-12s: %(levelname)-8s %(message)s')
        # tell the handler to use this format
        console.setFormatter(formatter)
        # add the handler to the root logger
        logging.getLogger('').addHandler(console)

        # Now, define a couple of other loggers which might represent areas in your
        # application:

        return logging.getLogger(logging_name)

上面太复杂了，给一个简单示例：

import logging
import logging.handlers
 
# logging初始化工作
logging.basicConfig()
 
# nor的初始化工作
nor = logging.getLogger("nor")
nor.setLevel(logging.INFO)
 
# 添加TimedRotatingFileHandler到nor
# 定义一个1分钟换一次log文件的handler
filehandler = logging.handlers.TimedRotatingFileHandler(
        "logging_test2", 'M', 1, 0)
# 设置后缀名称，跟strftime的格式一样
filehandler.suffix = "%Y%m%d-%H%M.log"
nor.addHandler(filehandler)

一些参数解释：

TimedRotatingFileHandler的构造函数定义如下（2.5版本API为例）：

TimedRotatingFileHandler(filename [,when [,interval [,backupCount]]])

filename 是输出日志文件名的前缀

when 是一个字符串的定义如下：

“S”: Seconds
“M”: Minutes
“H”: Hours
“D”: Days
“W”: Week day (0=Monday)
“midnight”: Roll over at midnight

interval 是指等待多少个单位when的时间后，Logger会自动重建文件，当然，这个文件的创建

取决于filename+suffix，若这个文件跟之前的文件有重名，则会自动覆盖掉以前的文件，所以

有些情况suffix要定义的不能因为when而重复。

backupCount 是保留日志个数。默认的0是不会自动删除掉日志。若设10，则在文件的创建过程中

库会判断是否有超过这个10，若超过，则会从最先创建的开始删除。

参考资料：

1、日志操作手册

2、python logging模块使用教程

3、python3 中文日志记录

4、【Python】python文件打开方式详解——a、a+、r+、w+、rb、rt区别

5、How to write to a file, using the logging Python module?