The python logging level is related to the “importance” of the log. For example, an “error” log is a top priority and should be considered more urgent than a “warn” log. A “debug” log is usually only useful when the application is being debugged.
Python has six log levels with each one assigned a specific integer indicating the severity of the log:
- NOTSET=0
- DEBUG=10
- INFO=20
- WARN=30
- ERROR=40
- CRITICAL=50
Python logging level example
Simple example code. The logging module has simple methods that can be used right away without any configuration.
import logging
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')
Output:
Note: that a root logger is used and only three messages were written. This is because, by default, only messages with level warnings and up are written.
Logging into a file
import logging
logging.basicConfig(filename='example.log', encoding='utf-8', level=logging.DEBUG)
logging.debug('This message should go to the log file')
logging.info('So should this')
logging.warning('And this, too')
logging.error('And non-ASCII stuff, too, like Øresund and Malmö')The standard levels and their applicability are described below (in increasing order of severity):
| Level | When it’s used |
|---|---|
DEBUG | Detailed information, is typical of interest only when diagnosing problems. |
INFO | Confirmation that things are working as expected. |
WARNING | An indication that something unexpected happened, or indicative of some problem in the near future (e.g. ‘disk space low’). The software is still working as expected. |
ERROR | Due to a more serious problem, the software has not been able to perform some functions. |
CRITICAL | A serious error indicates that the program itself may be unable to continue running. |
Source: https://docs.python.org/3/howto/logging.html
Do comment if you have any doubts or suggestions on this Python log topic.
Note: IDE: PyCharm 2021.3.3 (Community Edition)
Windows 10
Python 3.10.1
All Python Examples are in Python 3, so Maybe its different from python 2 or upgraded versions.