Python logging split between stdout and stderr

python logging stderr
crosswired picture crosswired · Apr 17, 2013 · Viewed 19.3k times · Source

Is it possible to have python logging messages which are INFO or DEBUG to go to stdout and WARNING or greater to go to stderr?

Answer

crosswired picture crosswired · Apr 17, 2013

This seems to do what I want:

#!/usr/bin/python
import sys
import logging


class InfoFilter(logging.Filter):
    def filter(self, rec):
        return rec.levelno in (logging.DEBUG, logging.INFO)


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

h1 = logging.StreamHandler(sys.stdout)
h1.setLevel(logging.DEBUG)
h1.addFilter(InfoFilter())
h2 = logging.StreamHandler()
h2.setLevel(logging.WARNING)

logger.addHandler(h1)
logger.addHandler(h2)

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