Python Logging - set date as file name

Question

I am working on implementing logging in my Python project and hit a bit. I am trying to configure my log so that Handlers and Formatters are all organized in a configuration file. What I'm trying to do at the moment is to configure mine fileHandlerso that it creates a log file that looks something like this: YYYY_MM_DD.logobviously with Y representing the year, M representing the month, and D representing the day.

Here is what I did with my configuration file:

[loggers]
keys=root,MainLogger

[handlers]
keys=fileHandler, consoleHandler

[formatters]
keys=logFormatter, consoleFormatter

[logger_root]
level=DEBUG
handlers=fileHandler

[logger_MainLogger]
level=DEBUG
handlers=fileHandler, consoleHandler
qualname=MainLogger
propagate=0

[handler_consoleHandler]
class=StreamHandler
level=DEBUG
formatter=consoleFormatter
args=(sys.stdout,)

[handler_fileHandler]
class=FileHandler
level=DEBUG
formatter=logFormatter
args=(datetime.now().strftime('%Y_%m_%d.log'), 'a')

[formatter_logFormatter]
format=%(asctime)s | %(levelname)-8s | %(lineno)04d | %(message)s

[formatter_consoleFormatter]
format=%(asctime)s | %(levelname)-8s | %(fillname)s-%(funcName)s-%(lineno)04d | %message)s

The file I use to verify the configuration is pretty simple:

import logging
import logging.config

logging.config.fileConfig('logging.conf')
logger = logging.getLogger('MainLogger')
logger.debug("TEST")

The specific error that I am currently receiving is:

configparser.InterpolationSyntaxError: '%' must be followed by '%' or '(', found: "%Y_%m_%d.log'), 'a')"

%Y, %m %d, , . , , ?

, test.log, , , , , .

Answer 1

datetime , , . Filehandler python:

import logging.config
from datetime import datetime

logging.config.fileConfig('aaa.conf')
logger = logging.getLogger('MainLogger')

fh = logging.FileHandler('{:%Y-%m-%d}.log'.format(datetime.now()))
formatter = logging.Formatter('%(asctime)s | %(levelname)-8s | %(lineno)04d | %(message)s')
fh.setFormatter(formatter)

logger.addHandler(fh)
logger.debug("TEST")

.

, , , filename fillname ( message.

[loggers]
keys=root,MainLogger

[handlers]
keys=consoleHandler

[formatters]
keys=consoleFormatter

[logger_root]
level=DEBUG
handlers=consoleHandler

[logger_MainLogger]
level=DEBUG
handlers=consoleHandler
qualname=MainLogger
propagate=0

[handler_consoleHandler]
class=StreamHandler
level=DEBUG
formatter=consoleFormatter
args=(sys.stdout,)

[formatter_consoleFormatter]
format=%(asctime)s | %(levelname)-8s | %(filename)s-%(funcName)s-%(lineno)04d | %(message)s

.

Answer 2

.

,

args=(datetime.now().strftime('%Y_%m_%d.log'), 'a')

,

args=(\__import__("datetime").datetime.now().strftime('%Y_%m_%d.log'), 'a')

( № 3): http://python-reference.readthedocs.io/en/latest/docs/functions/eval.html

Answer 3

, Python TimedRotatingFileHandler. .

-

• Python 2: https://docs.python.org/2/library/logging.handlers.html#timedrotatingfilehandler
• Python 3: https://docs.python.org/3/library/logging.handlers.html#timedrotatingfilehandler

, . , .

, , , "% Y-% m-% d", , . , .

Answer 4

, :

from datetime inport datetime

logging.config.fileConfig('logging.conf')
logging.basicConfig(filename = datetime.now().strftime('%Y_%m_%d.log'))

Answer 5

"%" -characters , , (Python 3.5):

:

[handler_fileHandler]
class=FileHandler
level=DEBUG
formatter=defaultFormatter
args=(__import__("datetime").datetime.now().strftime('/your_path/your_file_name_%%Y-%%m-%%d_%%H-%%M-%%S.log'), 'a')

Answer 6

, . , .

import logging
from datetime import datetime

# Create logger.
logger = logging.getLogger('MainLogger')
logger.setLevel(logging.DEBUG)

# Create filehandler with desired filename.
fh = logging.FileHandler('{}.log'.format(datetime.now().strftime('%Y_%m_%d')))
fh.setLevel(logging.DEBUG)
log_formatter = logging.Formatter('%(asctime)s | %(levelname)-8s | %(lineno)04d | %(message)s')
fh.setFormatter(log_formatter)

# Add filehandler to logger.
logger.addHandler(fh)

, a (append) mode FileHandler.

Answer 7

from datetime import datetime
log_file = str(datetime.utcnow().strftime('%m_%d_%Y_%I_%M_%S')) + '.log'
logging.basicConfig(filename=log_file, format='%(levelname)s | %(asctime)s | %(message)s', datefmt='%m/%d/%Y %I:%M:%S %p', level=logging.DEBUG)

: 04_30_2018_10_03_01.log

Answer 8

, , logging.conf logging.config.fileConfig(), . :

logging.conf

args=('my_log_%(date)s.log','w')

python.py

import logging.conf
logging.conf.fileConfig('logging.conf', defaults={'date':datetime.now()}

, .

Any number of variables can be used in the same way.