I'm confused by logging. It seems like Prefect configures its own logging at import time (ugh) and that it's configured to only log warning messages from tasks. How do I change this to ensure all INFO messages are displayed when running locally?

Hi @oliland - if you’re only seeing Warning messages, that may be a setting on your machine. Prefect is configured to show

INFO

messages by default, as you can see here: https://github.com/PrefectHQ/prefect/blob/master/src/prefect/config.toml#L26. If you need to change this directly, you can set the environment variable

PREFECT__LOGGING__LEVEL=INFO

I gave that a try but still no joy. Here's a minimal repro of what I'd like to do:

logger = logging.getLogger(__name__)

@task(name="Test logging")
def test_logging():
    <http://logger.info|logger.info>("Hidden by default")
    logger.warning("Shown by default")

with Flow("test") as flow:
    test_logging()
flow.run()

Ah, you’re expecting Prefect to change your global logging settings. It only affects loggers within the prefect namespace. Use our logging utility to grab one of those loggers, like this:

Thanks for the help - I'm still a bit lost though, as that was just a toy example. Here's a better example:

import mypackage


@task(name="Test logging")
def test_logging():
    my_package.run()

with Flow("test") as flow:
    test_logging()
flow.run()

with this setup, the prefect logger spits out

WARNING

messages from

mypackage

- but not

INFO

messages. How can I change that?

I’m afraid I can’t say without seeing all the code. As long as you’re using a logger generated by

prefect.utilities.get_logger

, it will respect the log setting in

prefect.config.logging.level

is there a way to disable all of prefect's log handlers? as calling

logging.basicConfig(level=<http://logging.INFO|logging.INFO>)

solves this issue for me, but it means I get double log entries

Python’s default is Warning+, so if you’re using any Python logger without modifying

logging.basicConfig

you’ll only get warning and higher

right - I normally call

basicConfig

myself - so I guess I'm just missing a way to change the default

Got it. I think what we actually should consider is a way to let Prefect control global logging if the user wants

this works for me though - thanks for the help!

prefect.utilities.logging.get_logger().handlers = []
logging.basicConfig(level=<http://logging.INFO|logging.INFO>)

:yes: Just PR’d a first cut at a Logging concept doc, will follow up with more this week!