python的日志处理

简单的日志处理示例

import logging
LOG_FILENAME = 'example.log'
logging.basicConfig(filename=LOG_FILENAME,level=logging.DEBUG)
logging.debug('This message should go to the log file')
##输出
DEBUG:root:This message should go to the log file

在上面的示例中，会看到所有的日志信息都包含一个root，root就是一个logger名称，在日志模块中可以设置不同的logger，每个logger可以有不同的配置，但是每个新的logger会“继承”logging模块的

import logging

logging.basicConfig(level=logging.WARNING)

logger1 = logging.getLogger('package1.module1')
logger2 = logging.getLogger('package2.module2')

logger1.warning('This message comes from one module')
logger2.warning('And this message comes from another module')

输出:

WARNING:package1.module1:This message comes from one module
WARNING:package2.module2:And this message comes from another module

python日志的配置方法

python的日志配置有三种方法：

1、 显式创建loggers，handlers，foramtters对象，调用对应的配置方法

2、创建logging配置文件，用fileConfig()函数读取配置文件

3、创建配置信息字典，将其传给dictConfig()函数

方法一：

import logging

# create logger
logger = logging.getLogger("simple_example")
logger.setLevel(logging.DEBUG)

# create console handler and set level to debug
ch = logging.StreamHandler()
ch.setLevel(logging.DEBUG)

# create formatter
formatter = logging.Formatter("%(asctime)s - %(name)s - %(levelname)s - %(message)s")

# add formatter to ch
ch.setFormatter(formatter)

# add ch to logger
logger.addHandler(ch)

# "application" code
logger.debug("debug message")
logger.info("info message")
logger.warn("warn message")
logger.error("error message")
logger.critical("critical message")

输出：

2016-02-02 15:43:44,575 - simple_example - DEBUG - debug message
2016-02-02 15:43:44,578 - simple_example - INFO - info message
2016-02-02 15:43:44,578 - simple_example - WARNING - warn message
2016-02-02 15:43:44,578 - simple_example - ERROR - error message
2016-02-02 15:43:44,578 - simple_example - CRITICAL - critical message

方法二：

import logging
import logging.config

logging.config.fileConfig("logging.conf")

# create logger
logger = logging.getLogger("simpleExample")

# "application" code
logger.debug("debug message")
logger.info("info message")
logger.warn("warn message")
logger.error("error message")
logger.critical("critical message")

logging.conf 文件

[loggers]
keys=root,simpleExample

[handlers]
keys=consoleHandler

[formatters]
keys=simpleFormatter

[logger_root]
level=DEBUG
handlers=consoleHandler

[logger_simpleExample]
level=DEBUG
handlers=consoleHandler
qualname=simpleExample
propagate=0

[handler_consoleHandler]
class=StreamHandler
level=DEBUG
formatter=simpleFormatter
args=(sys.stdout,)

[formatter_simpleFormatter]
format=%(asctime)s - %(name)s - %(levelname)s -
4000
%(message)s
datefmt=

输出：

2016-02-02 16:28:41,075 - simpleExample - DEBUG - debug message
2016-02-02 16:28:41,075 - simpleExample - INFO - info message
2016-02-02 16:28:41,075 - simpleExample - WARNING - warn message
2016-02-02 16:28:41,075 - simpleExample - ERROR - error message
2016-02-02 16:28:41,075 - simpleExample - CRITICAL - critical message

方法三

import logging
import logging.config
import yaml

#logging.config.fileConfig("logging.conf")
input = yaml.load(file('dict.conf'))
logging.config.dictConfig(input)
# create logger
logger = logging.getLogger("simpleExample")

# "application" code
logger.debug("debug message")
logger.info("info message")
logger.warn("warn message")
logger.error("error message")
logger.critical("critical message")

dict.conf文件 ：

version: 1
formatters:
simple:
format: format=%(asctime)s - %(name)s - %(levelname)s - %(message)s
handlers:
console:
class: logging.StreamHandler
level: DEBUG
formatter: simple
stream: ext://sys.stdout
loggers:
simpleExample:
level: DEBUG
handlers: [console]
propagate: no
root:
level: DEBUG
handlers: [console]

输出：

format=2016-02-02 17:09:54,104 - simpleExample - DEBUG - debug message
format=2016-02-02 17:09:54,104 - simpleExample - INFO - info message
format=2016-02-02 17:09:54,104 - simpleExample - WARNING - warn message
format=2016-02-02 17:09:54,104 - simpleExample - ERROR - error message
format=2016-02-02 17:09:54,104 - simpleExample - CRITICAL - critical message