避免使用 `logger=logging.getLogger(__name__)`

Question

我们按照 django 文档告诉我们的方式设置日志记录：

https://docs.djangoproject.com/en/2.1/topics/logging/#using-logging

# import the logging library
import logging

# Get an instance of a logger
logger = logging.getLogger(__name__)

def my_view(request, arg1, arg):
    ...
    if bad_mojo:
        # Log an error message
        logger.error('Something went wrong!')

我想在每个想要记录的 Python 文件中避免这一行：

logger = logging.getLogger(__name__)

我希望它简单：

logging.error('Something went wrong!')

但我们想保留一个特性：我们想在日志输出中看到 Python 文件名。

到目前为止，我们使用这种格式：

'%(asctime)s %(name)s.%(funcName)s +%(lineno)s: %(levelname)-8s [%(process)d] %(message)s'

示例输出：

2016-01-11 12:12:31 myapp.foo +68: ERROR Something went wrong

如何避免logger = logging.getLogger(__name__)？

Answer 1

路径名呢？来自https://docs.python.org/2/library/logging.html#formatter-objects

/Users/jluc/kds2/wk/explore/test_so_41.py

import logging

#another module, just to have another file...
import test_so_41b

#not so much to use basicConfig as a quick usage of %(pathname)s
logging.basicConfig(level=logging.DEBUG,
                    format='%(pathname)s %(asctime)s %(levelname)s %(message)s',
                    # filename='/tmp/myapp.log',
                    # filemode='w',
                    )

logging.debug('A debug message')
logging.info('Some information')
logging.warning('A shot across the bows')

test_so_41b.dosomething("hey there")

/Users/jluc/kds2/wk/explore/test_so_41b.py

import logging

def dosomething(msg):
    logging.info(msg)

audrey:explore jluc$ python test_so_41.py

输出：

test_so_41.py 2016-01-16 14:46:57,997 DEBUG A debug message
test_so_41.py 2016-01-16 14:46:57,997 INFO Some information
test_so_41.py 2016-01-16 14:46:57,997 WARNING A shot across the bows
/Users/jluc/kds2/wk/explore/test_so_41b.py 2016-01-16 14:46:57,997 INFO hey there

Answer 2

您可以使用logging.basicConfig 定义通过logging 可用的默认接口，如下所示：

import logging
logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s %(name)s.%(funcName)s +%(lineno)s: %(levelname)-8s [%(process)d] %(message)s',
                    )

现在，只要您在应用程序的任何位置执行以下操作，就会使用此定义：

import logging
logging.error(...)

虽然__name__ 不可用，但可通过可用于错误字符串格式化的默认LogRecord attributes 获得等效（和其他选项） - 包括module、filename 和pathname。以下是对此的两个脚本演示：

scripta.py

import logging
logging.basicConfig(level=logging.DEBUG,
                    format='%(asctime)s %(module)s %(name)s.%(funcName)s +%(lineno)s: %(levelname)-8s [%(process)d] %(message)s',
                    )

from scriptb import my_view

my_view()

scriptb.py

import logging

def my_view():
    # Log an error message
    logging.error('Something went wrong!')

日志定义在scripta.py 中定义，并添加了module 参数。在scriptb.py 中，我们只需导入logging 即可访问此定义的默认值。运行scripta.py 时会生成以下输出：

2016-01-14 13:22:24,640 scriptb root.my_view +9: ERROR    [14144] Something went wrong!

其中显示了发生错误记录的模块 (scriptb)。

根据this answer，您可以继续使用来自 Django 的任何每个模块的日志配置，方法是关闭 Django 处理并设置根处理程序，如下所示：

# settings.py - django config
LOGGING_CONFIG = None # disables Django handling of logging
LOGGING = {...}  # your standard Django logging configuration

import logging.config
logging.config.dictConfig(LOGGING)