Python log files and output to the screen at the same time

Python log files and output to the screen at the same time

1. log output to the screen

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import logging

logging.basicConfig(level=logging.NOTSET, format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')

logging.debug('This is a debug message.')
logging.info('This is an info message.')
logging.warning('This is a warning message.')
logging.error('This is an error message.')
logging.critical('This is a critical message.')

The default level is logging.WARNING, below this level is not output. If you need to display less than logging.WARNING level of content can be introduced logging.NOTSET levels to display.

DEBUG - print the entire log. For more information, usually only in the diagnosis of the problem.
INFO - Print INFO, WARNING, ERROR, CRITICAL level logging. Make sure everything runs as expected.
WARNING - Print WARNING, ERROR, CRITICAL level logging. Show some of the problems in the near future, this software can also work as expected.
ERROR - Print ERROR, CRITICAL level logging. A more serious problem, the software did not perform some functions.
CRITICAL: print CRITICAL level. A serious error, indicating that the program itself may not continue to run.

/usr/bin/python2.7 /home/strong/git_workspace/MonoGRNet/test.py
2019-06-26 16:00:45,990 - root - DEBUG - This is a debug message.
2019-06-26 16:00:45,990 - root - INFO - This is an info message.
2019-06-26 16:00:45,990 - root - WARNING - This is a warning message.
2019-06-26 16:00:45,990 - root - ERROR - This is an error message.
2019-06-26 16:00:45,990 - root - CRITICAL - This is a critical message.

Process finished with exit code 0

2. Log To File

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import logging
import os.path
import time

logger = logging.getLogger()
logger.setLevel(logging.DEBUG)

time_line = time.strftime('%Y%m%d%H%M', time.localtime(time.time()))

print(os.getcwd())
log_path = os.path.dirname(os.getcwd()) + '/'
logfile = log_path + time_line + '.log'

handler = logging.FileHandler(logfile, mode='w')
handler.setLevel(logging.INFO)

formatter = logging.Formatter("%(asctime)s - %(filename)s[line:%(lineno)d] - %(levelname)s: %(message)s")
handler.setFormatter(formatter)

logger.addHandler(handler)

logger.debug('This is a debug message.')
logger.info('This is an info message.')
logger.warning('This is a warning message.')
logger.error('This is an error message.')
logger.critical('This is a critical message.')

/usr/bin/python2.7 /home/strong/git_workspace/MonoGRNet/test.py
/home/strong/git_workspace/MonoGRNet

Process finished with exit code 0

201906261627.log

2019-06-26 16:27:26,899 - test.py[line:30] - INFO: This is an info message.
2019-06-26 16:27:26,899 - test.py[line:31] - WARNING: This is a warning message.
2019-06-26 16:27:26,899 - test.py[line:32] - ERROR: This is an error message.
2019-06-26 16:27:26,899 - test.py[line:33] - CRITICAL: This is a critical message.

3. The log files and output to the screen at the same time

#!/usr/bin/env python
# -*- coding: utf-8 -*-

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import logging
import os.path
import time

logger = logging.getLogger(__name__)
logger.setLevel(level=logging.DEBUG)

time_line = time.strftime('%Y%m%d%H%M', time.localtime(time.time()))

print(os.getcwd())
log_path = os.path.dirname(os.getcwd()) + '/'
logfile = log_path + time_line + '.log'

handler = logging.FileHandler(logfile, mode='w')
handler.setLevel(logging.INFO)

formatter = logging.Formatter("%(asctime)s - %(filename)s[line:%(lineno)d] - %(levelname)s: %(message)s")
handler.setFormatter(formatter)

console = logging.StreamHandler()
console.setLevel(logging.WARNING)

logger.addHandler(handler)
logger.addHandler(console)

logger.debug('This is a debug message.')
logger.info('This is an info message.')
logger.warning('This is a warning message.')
logger.error('This is an error message.')
logger.critical('This is a critical message.')

/usr/bin/python2.7 /home/strong/git_workspace/MonoGRNet/test.py
/home/strong/git_workspace/MonoGRNet
This is a warning message.
This is an error message.
This is a critical message.

Process finished with exit code 0

201906261636.log

2019-06-26 16:36:38,385 - test.py[line:34] - INFO: This is an info message.
2019-06-26 16:36:38,385 - test.py[line:35] - WARNING: This is a warning message.
2019-06-26 16:36:38,385 - test.py[line:36] - ERROR: This is an error message.
2019-06-26 16:36:38,385 - test.py[line:37] - CRITICAL: This is a critical message.