Source code
Revision control
Copy as Markdown
Other Tools
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
import logging
class LoggingMixin(object):
"""Provides functionality to control logging."""
def populate_logger(self, name=None):
"""Ensure this class instance has a logger associated with it.
Users of this mixin that call log() will need to ensure self._logger is
a logging.Logger instance before they call log(). This function ensures
self._logger is defined by populating it if it isn't.
"""
if hasattr(self, "_logger"):
return
if name is None:
name = ".".join([self.__module__, self.__class__.__name__])
self._logger = logging.getLogger(name)
def log(self, level, action, params, format_str):
"""Log a structured log event.
A structured log event consists of a logging level, a string action, a
dictionary of attributes, and a formatting string.
The logging level is one of the logging.* constants, such as
logging.INFO.
The action string is essentially the enumeration of the event. Each
different type of logged event should have a different action.
The params dict is the metadata constituting the logged event.
The formatting string is used to convert the structured message back to
human-readable format. Conversion back to human-readable form is
performed by calling format() on this string, feeding into it the dict
of attributes constituting the event.
Example Usage:
.. code-block:: python
self.log(logging.DEBUG, 'login', {'username': 'johndoe'},
'User login: {username}')
"""
self._logger.log(level, format_str, extra={"action": action, "params": params})