在Python中使用root记录器或命名记录器更好吗 [英] Is it better to use root logger or named logger in Python

问题描述

我正在尝试找出跨多个模块使用python登录的最佳实践.我在这里看到: http://docs.python.org/2/howto/logging#从多个模块进行记录，了解如何使用根记录器跨多个模块进行记录.正如该链接所指出的那样，您无法确定消息来自应用程序的哪个位置，因为它们都显示名称"root".

I am trying to figure out the best practice for using logging in python across multiple modules. I see here: http://docs.python.org/2/howto/logging#logging-from-multiple-modules on how to use the root logger to log across multiple modules. As the link points out though, you can't tell where in your application your messages come from as they all show name "root."

在我看来，有两种选择(假设我的模块不在包结构中，而只是同一文件夹中的一堆模块):

It seems to me there are two options (this assumes my modules are NOT in a package structure, but are just a bunch of modules in the same folder):

1)使用示例中的root记录器，但更改日志格式以包括文件名:

1) Use the root logger as in the example, but change the log formatting to include the filename:

# myapp.py
import logging
import mylib

def main():
    logging.basicConfig(format='%(asctime)s %(filename)s %(levelname)s: %(message)s', datefmt='%m/%d/%Y %I:%M:%S %p', level=logging.INFO)  #filename='myapp.log', 
    logging.info('Started')
    mylib.do_something()
    logging.info('Finished')

if __name__ == '__main__':
    main()

#mylib.py
import logging

def do_something():
    logging.info('Do something')




In [4]: import myapp

In [5]: myapp.main()
03/06/2014 12:22:07 PM myapp.py INFO: Started
03/06/2014 12:22:07 PM mylib.py INFO: Do something
03/06/2014 12:22:07 PM myapp.py INFO: Finished

2)在主应用程序中使用root记录器，在子模块中使用命名记录器，并以日志格式使用名称"而不是文件名":

2) Use a root logger in the main app but a named logger in the submodules, and use 'name' instead of 'filename' in the log format:

# myapp.py
import logging
import mylib

def main():
    #logging.basicConfig(format='%(asctime)s %(filename)s %(levelname)s: %(message)s', datefmt='%m/%d/%Y %I:%M:%S %p', level=logging.INFO)  #filename='myapp.log', 
    logging.basicConfig(format='%(asctime)s %(name)s %(levelname)s: %(message)s', datefmt='%m/%d/%Y %I:%M:%S %p', level=logging.INFO)  #filename='myapp.log', 
    logging.info('Started')
    mylib.do_something()
    logging.info('Finished')

if __name__ == '__main__':
    main()

#mylib.py
import logging

def do_something():
    #logging.info('Do something')
    logger = logging.getLogger(__name__)
    logger.info('Do something')



In [3]: import myapp

In [4]: myapp.main()
03/06/2014 12:27:29 PM root INFO: Started
03/06/2014 12:27:29 PM mylib INFO: Do something
03/06/2014 12:27:29 PM root INFO: Finished

推荐答案

Vinay Sajip(日志记录模块的维护者)在此处进行了推荐与选项#2相似，不同之处在于，即使在myapp中，您也可以在任何地方使用命名记录器:

Vinay Sajip (maintainer of the logging module) makes a recommendation here which is similar to your option #2, except that you could use a named logger everywhere, even in myapp:

import logging
import mylib
logger = logging.getLogger(__name__)

def main():
    logging.basicConfig(format='%(asctime)s %(module)s %(levelname)s: %(message)s',
                        datefmt='%m/%d/%Y %I:%M:%S %p', level=logging.INFO)  
    logger.info('Started')
    mylib.do_something()
    logger.info('Finished')

if __name__ == '__main__':
    main()

产生

03/06/2014 12:59:25 PM myapp INFO: Started
03/06/2014 12:59:25 PM mylib INFO: Do something
03/06/2014 12:59:25 PM myapp INFO: Finished

请注意，如果使用%(module)s而不是%(name)s，则会在root或myapp.py或__main__之前获得myapp.

Note that if you use %(module)s instead of %(name)s, then you get myapp where before you got root or myapp.py, or __main__.

如果总是将myapp称为脚本，有时作为模块导入，则始终使用logger的这种对称性可能特别有用.

This symmetry -- of always using logger -- may be especially useful if myapp is sometimes called as a script and sometimes imported as a module.

这篇关于在Python中使用root记录器或命名记录器更好吗的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！