No handlers could be found for logger

python logging handler
qwerty picture qwerty · May 25, 2017 · Viewed 90.6k times · Source

I am newbie to python. I was trying logging in python and I came across No handlers could be found for logger error while trying to print some warning through logger instance. Below is the code I tried

import logging
logger=logging.getLogger('logger')
logger.warning('The system may break down')

And I get this error No handlers could be found for logger "logger"

What's confusing me is when I first try to print warning using logging and then through logger , it works fine, like

>>> import logging
>>> logging.warning('This is a WARNING!!!!')
WARNING:root:This is a WARNING!!!!
>>> 
>>> logger.warning('WARNING!!!!')
WARNING:logger:WARNING!!!!

Can someone throw some light on what's happening in second scenario?

Answer

phd picture phd · May 25, 2017

Call logging.basicConfig():

>>> import logging
>>> logging.basicConfig()
>>> logger = logging.getLogger('logger')
>>> logger.warning('The system may break down')
WARNING:logger:The system may break down

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