python日志输出(二)-logging输出

1.常用参数

• Level
  设置了输出 level，系统便只会输出 level 数值大于或等于该 level 的的日志结果，例如我们设置了输出日志 level 为 INFO，那么输出级别大于等于 INFO 的日志，如 WARNING、ERROR 等，DEBUG 和 NOSET 级别的不会输出。

等级	数值
CRITICAL	50
FATAL	50
ERROR	40
WARNING	30
WARN	30
INFO	20
DEBUG	10
NOTSET	0

• Formatter

格式	意义
%(levelno)s	打印日志级别的数值
%(levelname)s	打印日志级别的名称。
%(filename)s	打印当前执行程序名
%(pathname)s	打印当前执行程序的路径，其实就是sys.argv[0]。
%(funcName)s	打印日志的当前函数
%(lineno)d	打印日志的当前行号
%(asctime)s	打印日志的时间
%(thread)d	打印线程ID
%(threadName)s	打印线程名称
%(process)d	打印进程ID
%(processName)s	打印进程名称
%(module)	打印模块名称
%(message)s	打印日志信息

２.Handler模式

• libs\lib\log_test.py

import logging
logger = logging.getLogger('test.log_test')
def run():
    logger.info('Core Info')
    logger.debug('Core Debug')
    logger.error('Core Error')

• test.py

import logging
from logging.handlers import HTTPHandler
import sys
import libs.lib.log_test as log_test
#initial logger
logger = logging.getLogger("test")
logger.setLevel(level=logging.DEBUG)
# StreamHandler
stream_handler = logging.StreamHandler(sys.stdout)
stream_handler.setLevel(level=logging.DEBUG)
logger.addHandler(stream_handler)
# FileHandler
file_handler = logging.FileHandler('output.log')
file_handler.setLevel(level=logging.INFO)
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
file_handler.setFormatter(formatter)
logger.addHandler(file_handler)
# HTTPHandler
# http_handler = HTTPHandler(host='localhost:8001', url='log', method='POST')
# logger.addHandler(http_handler)
# Log
logger.info('This is a log info')
logger.debug('Debugging')
logger.warning('Warning exists')
logger.info('Finish')
#catch exception
try:
    result = 10 / 0
except Exception:
    logger.error('Faild to get result', exc_info=True)
    logger.exception('Faild to get result', exc_info=True)
log_test.run()

3. Config模式

• libs\lib\config.yaml

version: 1
formatters:
 brief:
   format: "%(asctime)s - %(message)s"
 simple:
   format: "%(asctime)s - %(name)s - %(levelname)s - %(message)s"
handlers:
 console:
   class : logging.StreamHandler
   formatter: brief
   level   : INFO
   stream  : ext://sys.stdout
 file:
   class : logging.FileHandler
   formatter: simple
   level: DEBUG
   filename: debug.log
 error:
   class: logging.handlers.RotatingFileHandler
   level: ERROR
   formatter: simple
   filename: error.log
   maxBytes: 10485760
   backupCount: 20
   encoding: utf8
loggers:
 main.core:
   level: DEBUG
   handlers: [console, file, error]
root:
 level: DEBUG
 handlers: [console]

• libs\lib\log_test.py

import logging
logger = logging.getLogger('test.log_test')
def run():
    logger.info('Core Info')
    logger.debug('Core Debug')
    logger.error('Core Error')

• test.py

import logging
import libs.lib.log_test as log_test
import yaml
import logging.config
import os

def setup_logging(default_path='config.yaml', default_level=logging.INFO):
    path = default_path
    if os.path.exists(path):
        with open(path, 'r', encoding='utf-8') as f:
            config = yaml.load(f)
            logging.config.dictConfig(config)
    else:
        logging.basicConfig(level=default_level)

def log():
    logging.debug('Start')
    logging.info('Exec')
    logging.info('Finished')

if __name__ == '__main__':
    yaml_path = 'E:\python_sample\libs\lib\config.yaml'
    setup_logging(yaml_path)
    log()
    log_test.run()