python - Which is the better way to enable/disable logging?

Question

Which is better way to enable/disable logging?

1) Changing log levels,

logging.disable(logging.CRITICAL)

2)

log = None

And logging messages this way,

if log: log.info("log message")

So that we can avoid unnecessary string constructions in case of logging disabled...

jarmod · Accepted Answer · 2025-01-11 19:14:25Z

1 is best, ideally via a configuration file or command line argument (--quiet)

2 will just clutter up your code

If you want to avoid expensive string construction (this is probably worthwhile about 0.001% of the time in my experience), use:

if logger.isEnabledFor(logging.DEBUG): logger.debug("Message with %s, %s", expensive_func1(), expensive_func2())

This assumes you have the current or root logger in logger. If you just use logging.debug(...) you need to check as follows: if logging.getLogger().isEnabledFor(logging.DEBUG): ....

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