Actually in Python it looks pretty much similar. There are different ways to do it. I usually create a logger class which is very simple:
import os
import logging
import settings # alternativly from whereever import settings
class Logger(object):
def __init__(self, name):
name = name.replace('.log','')
logger = logging.getLogger('log_namespace.%s' % name) # log_namespace can be replaced with your namespace
logger.setLevel(logging.DEBUG)
if not logger.handlers:
file_name = os.path.join(settings.LOGGING_DIR, '%s.log' % name) # usually I keep the LOGGING_DIR defined in some global settings file
handler = logging.FileHandler(file_name)
formatter = logging.Formatter('%(asctime)s %(levelname)s:%(name)s %(message)s')
handler.setFormatter(formatter)
handler.setLevel(logging.DEBUG)
logger.addHandler(handler)
self._logger = logger
def get(self):
return self._logger
Then if I want to log something in a class or module I simply import the logger and create an instance. Passing the class name will create one file for each class. The logger can then log messages to its file via debug, info, error, etc.:
from module_where_logger_is_defined import Logger
class MyCustomClass(object):
def __init__(self):
self.logger = Logger(self.__class__.__name__).get() # accessing the "private" variables for each class
def do_something():
...
self.logger.info('Hello')
def raise_error():
...
self.logger.error('some error message')
Updated answer
Over the years I changed how I am using Python logging quite a bit. Mostly based in good practices I configure the logging of the whole application once in whatever module is loaded first during startup of the application and then use individual loggers in each file. Example:
# app.py (runs when application starts)
import logging
import os.path
def main():
logging_config = {
'version': 1,
'disable_existing_loggers': False,
'formatters': {
'standard': {
'format': '%(asctime)s [%(levelname)s] %(name)s: %(message)s'
},
},
'handlers': {
'default_handler': {
'class': 'logging.FileHandler',
'level': 'DEBUG',
'formatter': 'standard',
'filename': os.path.join('logs', 'application.log'),
'encoding': 'utf8'
},
},
'loggers': {
'': {
'handlers': ['default_handler'],
'level': 'DEBUG',
'propagate': False
}
}
}
logging.config.dictConfig(logging_config)
# start application ...
if __name__ == '__main__':
main()
# submodule.py (any application module used later in the application)
import logging
# define top level module logger
logger = logging.getLogger(__name__)
def do_something():
# application code ...
logger.info('Something happended')
# more code ...
try:
# something which might break
except SomeError:
logger.exception('Something broke')
# handle exception
# more code ...
The above is the recommended way of doing this. Each module defines its own logger and can easily identify based on the __name__ attribute which message was logged in which module when you inspect the logs. This removes the boilerplate from my original answer and instead uses the logging.config module from the Python standard library.