Setting logging levels in logging.conf in Python

Question

I am trying to make it easy to debug my code as my project grows. I hate adding and removing print or debug statements (why not just leave them in?) The problem is the output becomes messy to read. I am trying to be able to set up logging in different files and levels so I can turn it on or off via the logging.conf configuration file.

Here is my code:

import logging.config
logging.config.fileConfig('logging.conf')
if __name__ == "__main__":
    one = logging.getLogger("oneLogger")
    two = logging.getLogger("twoLogger")
    one.debug("debug on one")
    one.info("info on one")
    one.warn("warn on one")
    one.error("error on one")
    one.critical("critical on one")
    two.debug("debug on two")
    two.info("info on two")
    two.warn("warn on two")
    two.error("error on two")
    two.critical("critical on two")

Here is my logging.conf file:

[loggers]
keys=root,oneLogger, twoLogger

[handlers]
keys=rootHandler, oneHandler, twoHandler

[formatters]
keys=rootFormatter,oneFormatter, twoFormatter

[logger_root]
level=DEBUG
handlers=rootHandler

[logger_oneLogger]
level=DEBUG
handlers=oneHandler
qualname=main
propagate=1

[logger_twoLogger]
level=CRITICAL
handlers=twoHandler
qualname=main
propagate=1

[handler_rootHandler]
class=StreamHandler
formatter=rootFormatter
args=(sys.stdout,)

[handler_oneHandler]
class=StreamHandler
formatter=oneFormatter
args=(sys.stdout,)

[handler_twoHandler]
class=StreamHandler
formatter=twoFormatter
args=(sys.stdout,)

[formatter_rootFormatter]
format=Root: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt=

[formatter_oneFormatter]
format=One: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt=

[formatter_twoFormatter]
format=Two: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt=

I would have expected this output:

One: 2016-12-22 16:36:32,414 - one - DEBUG - debug on one
One: 2016-12-22 16:36:32,414 - one - INFO - info on one
One: 2016-12-22 16:36:32,415 - one - WARNING - warn on one
One: 2016-12-22 16:36:32,417 - one - ERROR - error on one
One: 2016-12-22 16:36:32,417 - one - CRITICAL - critical on one
Two: 2016-12-22 16:36:32,421 - two - CRITICAL - critical on two

Instead I got this:

Root: 2016-12-22 16:36:32,414 - one - DEBUG - debug on one
Root: 2016-12-22 16:36:32,414 - one - INFO - info on one
Root: 2016-12-22 16:36:32,415 - one - WARNING - warn on one
Root: 2016-12-22 16:36:32,417 - one - ERROR - error on one
Root: 2016-12-22 16:36:32,417 - one - CRITICAL - critical on one
Root: 2016-12-22 16:36:32,418 - two - DEBUG - debug on two
Root: 2016-12-22 16:36:32,418 - two - INFO - info on two
Root: 2016-12-22 16:36:32,420 - two - WARNING - warn on two
Root: 2016-12-22 16:36:32,421 - two - ERROR - error on two
Root: 2016-12-22 16:36:32,421 - two - CRITICAL - critical on two

I was expecting that logger two would be limited to only CRITICAL logs and logger one would accept all logs. Instead, I was surprised to see that the root logger handled ALL of the logs.

What am I doing/assuming wrong?

Answer 1

Got it. It seems that "qualname" is what I was looking for and NOT the name of the logger itself:

Here is my code:

import logging.config
logging.config.fileConfig('logging.conf')
if __name__ == "__main__":
    one = logging.getLogger("one.oneLogger")
    one.debug("debug on one")
    one.info("info on one")
    one.warn("warn on one")
    one.error("error on one")
    one.critical("critical on one")
    two = logging.getLogger("two")
    two.debug("debug on two")
    two.info("info on two")
    two.warn("warn on two")
    two.error("error on two")
    two.critical("critical on two")
    root = logging.getLogger()
    root.debug("debug on root")
    root.info("info on root")
    root.warn("warn on root")
    root.error("error on root")
    root.critical("critical on root")

Here is my logging.conf file:

[loggers]
keys:root,twoLogger,oneLogger

[handlers]
keys:rootHandler,oneHandler,twoHandler

[formatters]
keys:rootFormatter,oneFormatter,twoFormatter

[logger_root]
level:DEBUG
handlers:rootHandler

[logger_oneLogger]
level:WARN
handlers:oneHandler
qualname:one
propagate:0

[logger_twoLogger]
level:CRITICAL
handlers:twoHandler
qualname:two
propagate:0

[handler_rootHandler]
class:StreamHandler
formatter:rootFormatter
args:(sys.stdout,)

[handler_oneHandler]
class:StreamHandler
formatter:oneFormatter
args:(sys.stdout,)

[handler_twoHandler]
class:StreamHandler
formatter:twoFormatter
args:(sys.stdout,)

[formatter_rootFormatter]
format:Root: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt:

[formatter_oneFormatter]
format:One: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt:

[formatter_twoFormatter]
format:Two: %(asctime)s - %(name)s - %(levelname)s - %(message)s
datefmt:

Here is my output:

One: 2016-12-24 12:46:14,244 - one.oneLogger - WARNING - warn on one
One: 2016-12-24 12:46:14,246 - one.oneLogger - ERROR - error on one
One: 2016-12-24 12:46:14,246 - one.oneLogger - CRITICAL - critical on one
Two: 2016-12-24 12:46:14,247 - two.twoLogger - CRITICAL - critical on two
Root: 2016-12-24 12:46:14,249 - root - DEBUG - debug on root
Root: 2016-12-24 12:46:14,249 - root - INFO - info on root
Root: 2016-12-24 12:46:14,250 - root - WARNING - warn on root
Root: 2016-12-24 12:46:14,250 - root - ERROR - error on root
Root: 2016-12-24 12:46:14,252 - root - CRITICAL - critical on root