【发布时间】：2014-09-30 23:08:51
【问题描述】：
伙计们，
我对一个我无法正确设置的 python 日志记录配置摸不着头脑。
假设我安装了以下软件包：
mypackage/
data/mypackage.logging.conf
module1.py
module2.py
scripts/main.py
由于脚本可以交互使用或从 crontab 运行，我有以下要求：
没有打印语句，一切都通过日志记录；
使用
timedRotatingFileHandler记录日志，总是在 DEBUG 级别；使用
mailinglogger.SummarisingLogger记录，总是在 INFO 级别；登录到控制台，级别默认设置为 INFO 或通过命令行选项覆盖。
问题是，我可以通过命令行更改日志级别，控制台日志级别也相应更改，但其他处理程序也更改了，我不希望... :-/
在日志记录配置文件中，我不确定我是否理解根记录器级别、其他记录器级别和处理程序级别设置之间的优先级。
这里是一些示例代码。任何线索将不胜感激:-)
# mypackage/data/mypackage.logging.conf
[loggers]
root,mypackage
[handlers]
keys=consoleHandler,timedRotatingFileHandler,summarisingHandler
[formatters]
keys=simpleFormatter,consoleFormatter,mypackageFormatter
[logger_root]
#level=INFO
handlers=consoleHandler
[logger_mypackage]
#level=INFO
handlers=timedRotatingFileHandler,summarisingHandler
qualname=mypackage
[handler_consoleHandler]
class=StreamHandler
#level=INFO
formatter=consoleFormatter
args=(sys.stdout,)
[handler_timedRotatingFileHandler]
class=logging.handlers.TimedRotatingFileHandler
level=DEBUG
formatter=mypackageFormatter
args=('mypackage.log', 'M', 1, 5)
[handler_summarisingHandler]
class=mailinglogger.SummarisingLogger
level=INFO
formatter=mypackageFormatter
args=('mypackage@someserver.somewhere.com', ('mypackage-alerts@somewhere.com',), 'relay.somewhere.com')
#mypackage/scripts/main.py:
import logging
import logging.config
import os
import sys
import mypackage.module1
import mypackage.module2
logging.config.fileConfig('data/mypackage.logging.conf')
log = logging.getLogger(__name__)
if __name__ == '__main__':
loglevel = 'INFO'
if len(sys.argv) > 1:
loglevel = sys.argv[1].upper()
logging.getLogger('').setLevel(getattr(logging, loglevel))
# or logging.getLogger('mypackage').setLevel(getattr(logging, loglevel)) ?
mypackage.module1.do_something()
mypackage.module2.do_something_else()
#mypackage/module1.py:
import logging
log = logging.getLogger(__name__)
log.addHandler(NullHandler())
def do_something():
log.debug("some debug message from:" + __name__)
log.info("some info message from:" + __name__)
log.error("some error message from:" + __name__)
#mypackage/module2.py:
import logging
log = logging.getLogger(__name__)
log.addHandler(NullHandler())
def do_something_else():
log.debug("some debug message from:" + __name__)
log.info("some info message from:" + __name__)
log.error("some error message from:" + __name__)
更新 1
与此同时，我发现了this answer，并以这种方式成功修改了我的代码：
#mypackage/scripts/main.py:
import logging
import logging.config
import os
import sys
import mailinglogger
import mypackage.module1
import mypackage.module2
def main():
# get the console log level from the command-line
loglevel = 'INFO'
if len(sys.argv) > 1:
loglevel = sys.argv[1].upper()
# create formatters
simple_formatter = logging.Formatter("%(name)s:%(levelname)s: %(message)s")
detailed_formatter = logging.Formatter("%(asctime)s %(name)s[%(process)d]: %(levelname)s - %(message)s")
# get a top-level "mypackage" logger,
# set its log level to DEBUG,
# BUT PREVENT IT from propagating messages to the root logger
#
log = logging.getLogger('mypackage')
log.setLevel(logging.DEBUG)
log.propagate = 0
# create a console handler
# and set its log level to the command-line option
#
console_handler = logging.StreamHandler(sys.stdout)
console_handler.setLevel(getattr(logging, loglevel))
console_handler.setFormatter(simple_formatter)
# create a file handler
# and set its log level to DEBUG
#
file_handler = logging.handlers.TimedRotatingFileHandler('mypackage.log', 'M', 1, 5)
file_handler.setLevel(logging.DEBUG)
file_handler.setFormatter(detailed_formatter)
# create a mail handler
# and set its log level to INFO
#
mail_handler = mailinglogger.SummarisingLogger(
'mypackage@someserver.somewhere.com', ('mypackage-alerts@somewhere.com',), 'relay.somewhere.com')
mail_handler.setLevel(logging.INFO)
mail_handler.setFormatter(detailed_formatter)
# add handlers to the "mypackage" logger
#
log.addHandler(console_handler)
log.addHandler(file_handler)
log.addHandler(mail_handler)
# let the modules do their stuff
# and log to the "mypackage.module1" and "mypackage.module2" loggers
#
mypackage.module1.do_something()
mypackage.module2.do_something_else()
if __name__ == '__main__':
main()
现在，我将尝试在 logging.config 文件中翻译它...
更新 2
这是我找到的最好的日志记录配置和代码组合。
在 mypackage.logging.conf 文件中，“mypackage”记录器是：
- 仅使用文件和电子邮件处理程序进行设置；
- 其传播设置为 false；
- 其级别设置为 DEBUG；
- 文件和电子邮件处理程序分别设置为 INFO 和 DEBUG。
#mypackage/data/mypackage.logging.conf
[loggers]
keys=root,mypackage
[handlers]
keys=consoleHandler,timedRotatingFileHandler,summarisingHandler
[formatters]
keys=simpleFormatter,consoleFormatter,mypackageFormatter
[logger_root]
#level=INFO
handlers=consoleHandler
[logger_mypackage]
level=DEBUG
handlers=timedRotatingFileHandler,summarisingHandler
qualname=mypackage
propagate=0
[handler_consoleHandler]
class=StreamHandler
#level=INFO
formatter=consoleFormatter
args=(sys.stdout,)
[handler_timedRotatingFileHandler]
class=logging.handlers.TimedRotatingFileHandler
level=DEBUG
formatter=mypackageFormatter
args=('mypackage.log', 'M', 1, 5)
[handler_summarisingHandler]
class=mailinglogger.SummarisingLogger
level=INFO
formatter=mypackageFormatter
args=('mypackage@someserver.somewhere.com', ('mypackage-alerts@somewhere.com',), 'relay.somewhere.com')
[formatter_consoleFormatter]
format=%(levelname)s: %(message)s
datefmt=
[formatter_mypackageFormatter]
format=%(asctime)s %(name)s[%(process)d]: %(levelname)s - %(message)s
datefmt=
在脚本中：
日志配置被读取；
（重新）创建了一个 console_formatter；
使用命令行选项的日志级别创建控制台处理程序，然后添加到“mypackage”记录器。
import logging
import logging.config
import os
import sys
import mypackage.module1
import mypackage.module2
def setup_logging(loglevel):
#
# load logging config from file
#
logging.config.fileConfig('data/mypackage.logging.conf')
# (re-)create formatter
console_formatter = logging.Formatter("%(name)s:%(levelname)s: %(message)s")
# create a console handler
# and set its log level to the command-line option
#
console_handler = logging.StreamHandler(sys.stdout)
console_handler.setFormatter(console_formatter)
console_handler.setLevel(getattr(logging, loglevel))
# add console handler to the pre-configured "mypackage" logger
#
logger = logging.getLogger('mypackage')
logger.addHandler(console_handler)
def main():
# get the console log level from the command-line
loglevel = 'INFO'
if len(sys.argv) > 1:
loglevel = sys.argv[1].upper()
# load logging config and setup console handler
#
setup_logging(loglevel)
# log from the script to the "mypackage.scripts.main" logger
#
log = logging.getLogger(__name__)
log.debug("some debug message from:" + __name__)
log.info("some info message from:" + __name__)
log.error("some error message from:" + __name__)
# let the modules do their stuff
# and log to the "mypackage.module1" and "mypackage.module2" loggers
#
mypackage.module1.do_something()
mypackage.module2.do_something_else()
if __name__== '__main__':
main()
如果处理程序在从配置文件加载时按名称“可寻址”，事情会更简单。
然后，我们可以在配置文件中设置 mypackage 控制台处理程序，并在代码中更改其日志级别，如下所示：
def setup_logging(loglevel):
logging.config.fileConfig('data/mypackage.logging.conf')
logger = logging.getLogger('mypackage')
console_handler = logger.getHandler('consoleHandler')
console_handler.setLevel(getattr(logging, loglevel))
也不需要重新创建格式化程序...
（最后更新：是的，我知道 https://docs.python.org/3/library/logging.config.html#incremental-configuration，但在这种情况下，我被 Python 2.6 困住了...... :-)
【问题讨论】：
-
您是要覆盖某些处理程序的日志级别，还是仅过滤？换句话说，
logging.warn("foo")应该作为DEBUG转储到文件处理程序，还是不被文件处理程序记录？ -
如果您想得到答案，请花点时间制作一个小示例，而不是复制/粘贴大量代码。