Python logging to multiple handlers, at different log levels?

Question

Folks,

I\'m scratching my head on a python logging config that I can\'t get right.

Let\'s say I have the following package installed:

mypacka         


        

Answer 1

Use dictConfig. Here is an example of logging to multiple files with separate handles in dictConfig. This isn't exactly what you are looking for, but you could modify this example and simply change the level of each handler that you are looking to use.

import os, logging
from logging.config import dictConfig

FORMAT = "%(asctime)s {app} [%(thread)d] %(levelname)-5s %(name)s - %(message)s. [file=%(filename)s:%(lineno)d]"
DATE_FORMAT = None


def setup_logging(name, level="INFO", fmt=FORMAT):
    formatted = fmt.format(app=name)
    log_dir = r'C:/log_directory'
    if not os.path.exists(log_dir):
        os.makedirs(log_dir)

    logging_config = {
        "version": 1,
        'disable_existing_loggers': False,
        "formatters": {
            'standard': {
                'format': formatted
            }
        },
        "handlers": {
            'default': {
                'class': 'logging.StreamHandler',
                'formatter': 'standard',
                'level': level,
                'stream': 'ext://sys.stdout'
            },
            'file': {
                'class': 'logging.handlers.TimedRotatingFileHandler',
                'when': 'midnight',
                'utc': True,
                'backupCount': 5,
                'level': level,
                'filename': '{}/app_manager.log'.format(log_dir),
                'formatter': 'standard',
            },
            'file2': {
                'class': 'logging.handlers.TimedRotatingFileHandler',
                'when': 'midnight',
                'utc': True,
                'backupCount': 5,
                'level': level,
                'filename': '{}/unified_log.log'.format(log_dir),
                'formatter': 'standard',
            }
        },
        "loggers": {
            "": {
                'handlers': ['default', 'file'],
                'level': level
            },
            "second_log": {
                'handlers': ['default', 'file2'],
                'level': level
            }
        }
    }

    dictConfig(logging_config)

log.setup_logging(name="log-name", level=LEVEL
logger = logging.getLogger(__name__)
second_logger = logging.getLogger('second_log')
second_logger.propagate = False

Answer 2

An approach to update your handler:

import logging

from rootmodule.mymodule import mylogger

def update_handler_level(logger,  handler_type, level="INFO"):
    # if not root logger user logger.parent
    for handler in logger.handlers or logger.parent.handlers:
        if isinstance(handler, handler_type):
            print(handler.level)
            handler.setLevel(getattr(logging, level, "INFO"))
            print(handler.level)

mylogger.debug('test')
update_handler_level(mylogger, logging.StreamHandler)
mylogger.debug('test')

My logging.cfg is pretty similar than your except the fact that the logger name si set in a constant module (a can do module rename without breaking the logging configuration)

To update from command line, you must have a mapping between your opts value and logging.Handler sub class name.