Change log level in unittest

Question

I have the impression (but do not find the documentation for it) that unittest sets the logging level to WARNING for all loggers. I would like to:

• be able to specify the logging level for all loggers, from the command line (when running the tests) or from the test module itself
• avoid unittest messing around with the application logging level: when running the tests I want to have the same logging output (same levels) as when running the application

How can I achieve this?

Answer 1

I don't believe unittest itself does anything to logging, unless you use a _CapturingHandler class which it defines. This simple program demonstrates:

import logging import unittest  logger = logging.getLogger(__name__)  class MyTestCase(unittest.TestCase):     def test_something(self):         logger.debug('logged from test_something')   if __name__ == '__main__':     # DEBUG for demonstration purposes, but you could set the level from     # cmdline args to whatever you like     logging.basicConfig(level=logging.DEBUG, format='%(name)s %(levelname)s %(message)s')     unittest.main() 

When run, it prints

__main__ DEBUG logged from test_something . ---------------------------------------------------------------------- Ran 1 test in 0.000s  OK 

showing that it is logging events at DEBUG level, as expected. So the problem is likely to be related to something else, e.g. the code under test, or some other test runner which changes the logging configuration or redirects sys.stdout and sys.stderr. You will probably need to provide more information about your test environment, or better yet a minimal program that demonstrates the problem (as my example above shows that unittest by itself doesn't cause the problem you're describing).