update statshandler logging message

[wyli]

Description

The recommendation in StatsHandler of setting the global logging config may not work in some cases (e.g. google colab and #5960) https://docs.python.org/3/library/logging.html#logging.basicConfig

MONAI/monai/handlers/stats_handler.py

Line 55 in 3eef61e

logging.basicConfig(stream=sys.stdout, level=logging.INFO)

in general we shouldn't recommend changing the root logger directly.

This PR changes the message to tune the module level loggers, updated example message will be:

.the effective log level of ignite.engine.engine.Engine higher than INFO, StatsHandler may not generate logs,
please use the following code before running the engine to enable it: 
                                                                                
import logging                                                              
logging.getLogger('ignite.engine.engine.Engine').setLevel(logging.INFO) 

the updated commands are tested in the colab example:
https://colab.research.google.com/drive/1boqy7ENpKrqaJoxFlbHIBnIODAs1Ih1T

Types of changes

• Non-breaking change (fix or new feature that would not break existing functionality).
• Breaking change (fix or new feature that would cause existing functionality to change).
• New tests added to cover the changes.
• Integration tests passed locally by running ./runtests.sh -f -u --net --coverage.
• Quick tests passed locally by running ./runtests.sh --quick --unittests --disttests.
• In-line docstrings updated.
• Documentation updated, tested make html command in the docs/ folder.

[Nic-Ma]

OK, I think the change is acceptable now. But please verify it with some bundles and workflow tutorials before merging.

Thanks.

[wyli]

OK, I think the change is acceptable now. But please verify it with some bundles and workflow tutorials before merging.

Thanks.

thanks, I've tested it in a bundle and tutorials, after merging this PR

this global setting can be avoided:

logging.basicConfig(stream=sys.stdout, level=logging.INFO)

new usage would be, either specify a logger name when creating StatsHandler:

monai.handlers.StatsHandler(name="train_stats"...)

or update the engine logger using ignite.utils.setup_logger:

trainer = ignite.engine.Engine(lambda x, y: [0.0])
ignite.utils.setup_logger(trainer.logger.name, reset=True)
monai.handlers.StatsHandler().attach(trainer)
trainer.run(range(3), max_epochs=4)

[wyli]

/build

[wyli]

/build

[Nic-Ma]

OK, I think the change is acceptable now. But please verify it with some bundles and workflow tutorials before merging.
Thanks.

thanks, I've tested it in a bundle and tutorials, after merging this PR

this global setting can be avoided:

logging.basicConfig(stream=sys.stdout, level=logging.INFO)

new usage would be, either specify a logger name when creating StatsHandler:

monai.handlers.StatsHandler(name="train_stats"...)

or update the engine logger using ignite.utils.setup_logger:

trainer = ignite.engine.Engine(lambda x, y: [0.0])
ignite.utils.setup_logger(trainer.logger.name, reset=True)
monai.handlers.StatsHandler().attach(trainer)
trainer.run(range(3), max_epochs=4)

Hi @wyli ,

I think your examples are python level, could you please share some usage examples for the bundle config?
Currently, bundles usually leverage this line config to run with correct logging:
https://github.com/Project-MONAI/model-zoo/blob/dev/models/spleen_ct_segmentation/configs/logging.conf#L11
Please show the recommendation change or how to update the existing bundles?
CC @yiheng-wang-nv .

Thanks in advance.