python - 本地函数无法识别记录器

Question

我有一个 python 代码(如下)，它在下面进一步发出错误，我不明白问题出在哪里。据我了解python HOWTO记录器应该可供定义记录器的 main() 调用的例程使用。我正在使用 python 2.7.10。

#!/usr/bin/python

import logging
import sys

def setup():
  logger.debug('some text')
  return 0

def main():
  logger = logging.getLogger('some_logger_name')
  logger.setLevel(logging.DEBUG)
  consoleHandler = logging.StreamHandler()
  consoleHandler.setLevel(logging.DEBUG)
  consoleHandler.setFormatter(logging.Formatter('%(levelname)s: %(message)s'))
  logger.addHandler(consoleHandler)

  ret = setup()

if __name__=='__main__':
  sys.exit(main())  # Exit python upon execution of main().

这是我运行 $python test.py 时收到的错误消息:

Traceback (most recent call last):
  File "test.py", line 20, in <module>
    sys.exit(main())  # Exit python upon execution of main().
  File "test.py", line 17, in main
    ret = setup()
  File "test.py", line 7, in setup
    logger.debug('some text')
NameError: global name 'logger' is not defined 

有人看到我的错误吗？

编辑:感谢到目前为止的回复!您能否解释一下我的版本和我上面提到的 python HOWTO 上的版本之间的区别(我在下面附加了相关摘录)。

If your program consists of multiple modules, here’s an example of how you could organize logging in it:

# myapp.py
import logging
import mylib

def main():
__logging.basicConfig(filename='myapp.log', level=logging.INFO)
__logging.info('Started')
__mylib.do_something()
__logging.info('Finished')

if __name__ == '__main__':
__main()

这是模块mylib.py:

# mylib.py
import logging

def do_something():
__logging.info('Doing something')

If you run myapp.py, you should see this in myapp.log:

INFO:root:Started
INFO:root:Doing something
INFO:root:Finished

which is hopefully what you were expecting to see. You can generalise this to multiple modules, using the pattern in mylib.py.

Arg，对于奇怪的编辑感到抱歉。我不明白我应该如何格式化引用的代码。

Answer 1

记录器是在 main() 中设置的局部变量您需要在全局空间中声明它。

logger=None
def setup():
  logger.debug('some text')
  return 0

def main():
  global logger
  logger = logging.getLogger('some_logger_name')
  logger.setLevel(logging.DEBUG)

  ret = setup()