How can I disable logging while running unit tests in Python Django?

Question

I am using a simple unit test based test runner to test my Django application.

My application itself is configured to use a basic logger in settings.py using:

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Answer 1

Is there a simple way to turn off logging in a global way, so that the application specific loggers aren't writing stuff out to the console when I run tests?

The other answers prevent "writing stuff out to the console" by globally setting the logging infrastructure to ignore anything. This works but I find it too blunt an approach. My approach is to perform a configuration change which does only what's needed to prevent logs to get out on the console. So I add a custom logging filter to my settings.py:

from logging import Filter

class NotInTestingFilter(Filter):

    def filter(self, record):
        # Although I normally just put this class in the settings.py
        # file, I have my reasons to load settings here. In many
        # cases, you could skip the import and just read the setting
        # from the local symbol space.
        from django.conf import settings

        # TESTING_MODE is some settings variable that tells my code
        # whether the code is running in a testing environment or
        # not. Any test runner I use will load the Django code in a
        # way that makes it True.
        return not settings.TESTING_MODE

And I configure the Django logging to use the filter:

LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'filters': {
        'testing': {
            '()': NotInTestingFilter
        }
    },
    'formatters': {
        'verbose': {
            'format': ('%(levelname)s %(asctime)s %(module)s '
                       '%(process)d %(thread)d %(message)s')
        },
    },
    'handlers': {
        'console': {
            'level': 'DEBUG',
            'class': 'logging.StreamHandler',
            'filters': ['testing'],
            'formatter': 'verbose'
        },
    },
    'loggers': {
        'foo': {
            'handlers': ['console'],
            'level': 'DEBUG',
            'propagate': True,
        },
    }
}

End result: when I'm testing, nothing goes to the console, but everything else stays the same.

Why Do This?

I design code that contains logging instructions that are triggered only in specific circumstances and that should output the exact data I need for diagnosis if things go wrong. Therefore I test that they do what they are supposed to do and thus completely disabling logging is not viable for me. I don't want to find once the software is in production that what I thought would be logged is not logged.

Moreover, some test runners (Nose, for instance) will capture logs during testing and output the relevant part of the log together with a test failure. It is useful in figuring out why a test failed. If logging is completely turned off, then there's nothing that can be captured.