I have a python program that is writing to a log file that is being rotated by Linux's logrotate command. When this happens I need to signal my program to stop writing to the old file and start writing to the new one. I can handle the signal but how do I tell python to write to the new file?
I am opening the file like this:
logging.basicConfig(format='%(asctime)s:%(filename)s:%(levelname)s:%(message)s',filename=log_file, level=logging.INFO)
and writing to it like this:
logging.log(level,"%s" % (msg))
The logging modules look very powerful but also overwhelming. Thanks.
TimedRotatingFileHandler. The TimedRotatingFileHandler class, located in the logging. handlers module, supports rotation of disk log files at certain timed intervals.
In information technology, log rotation is an automated process used in system administration in which log files are compressed, moved (archived), renamed or deleted once they are too old or too big (there can be other metrics that can apply here).
Don't use logging.basicConfig
, use WatchedFileHandler
. Here's how to use it.
import time
import logging
import logging.handlers
def log_setup():
log_handler = logging.handlers.WatchedFileHandler('my.log')
formatter = logging.Formatter(
'%(asctime)s program_name [%(process)d]: %(message)s',
'%b %d %H:%M:%S')
formatter.converter = time.gmtime # if you want UTC time
log_handler.setFormatter(formatter)
logger = logging.getLogger()
logger.addHandler(log_handler)
logger.setLevel(logging.DEBUG)
log_setup()
logging.info('Hello, World!')
import os
os.rename('my.log', 'my.log-old')
logging.info('Hello, New World!')
You may want to look at WatchedFileHandler to implement this, or as an alternative, implement log rotation with RotatingFileHandler, both of which are in the logging.handlers module.
from logging import handlers
handler = handlers.TimedRotatingFileHandler(filename, when=LOG_ROTATE)
handler.setFormatter(logging.Formatter(log_format, datefmt="%d-%m-%Y %H:%M:%S"))
#LOG_ROTATE = midnight
#set your log format
This should help you in handling rotating log
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With