结合所有现有答案和大量使用经验，我想我已经列出了所有需要做的事情，以确保完全无缝地使用新关卡。以下步骤假设您正在添加一个新级别 TRACE，其值为 logging.DEBUG - 5 == 5：
-
需要调用
logging.addLevelName(logging.DEBUG - 5, 'TRACE') 以在内部注册新级别，以便可以通过名称引用它。
- 需要将新级别作为属性添加到
logging 本身以保持一致性：logging.TRACE = logging.DEBUG - 5。
- 需要将名为
trace 的方法添加到logging 模块中。它的行为应该像 debug、info 等。
- 需要将一个名为
trace 的方法添加到当前配置的记录器类中。由于不能 100% 保证是 logging.Logger，因此请改用 logging.getLoggerClass()。
所有步骤都在下面的方法中说明：
def addLoggingLevel(levelName, levelNum, methodName=None):
"""
Comprehensively adds a new logging level to the `logging` module and the
currently configured logging class.
`levelName` becomes an attribute of the `logging` module with the value
`levelNum`. `methodName` becomes a convenience method for both `logging`
itself and the class returned by `logging.getLoggerClass()` (usually just
`logging.Logger`). If `methodName` is not specified, `levelName.lower()` is
used.
To avoid accidental clobberings of existing attributes, this method will
raise an `AttributeError` if the level name is already an attribute of the
`logging` module or if the method name is already present
Example
-------
>>> addLoggingLevel('TRACE', logging.DEBUG - 5)
>>> logging.getLogger(__name__).setLevel("TRACE")
>>> logging.getLogger(__name__).trace('that worked')
>>> logging.trace('so did this')
>>> logging.TRACE
5
"""
if not methodName:
methodName = levelName.lower()
if hasattr(logging, levelName):
raise AttributeError('{} already defined in logging module'.format(levelName))
if hasattr(logging, methodName):
raise AttributeError('{} already defined in logging module'.format(methodName))
if hasattr(logging.getLoggerClass(), methodName):
raise AttributeError('{} already defined in logger class'.format(methodName))
# This method was inspired by the answers to Stack Overflow post
# http://stackoverflow.com/q/2183233/2988730, especially
# http://stackoverflow.com/a/13638084/2988730
def logForLevel(self, message, *args, **kwargs):
if self.isEnabledFor(levelNum):
self._log(levelNum, message, args, **kwargs)
def logToRoot(message, *args, **kwargs):
logging.log(levelNum, message, *args, **kwargs)
logging.addLevelName(levelNum, levelName)
setattr(logging, levelName, levelNum)
setattr(logging.getLoggerClass(), methodName, logForLevel)
setattr(logging, methodName, logToRoot)
您可以在我维护的实用程序库haggis 中找到更详细的实现。函数haggis.logs.add_logging_level 是这个答案的更适合生产的实现。