pytest - specify log level from the CLI command running the tests

问题

my team and I are using Pytest + Jenkins to automate our product testing. we have been using the standard Logging lib of python to get proper log messages during testing, before and after each test etc. we have multiple layers of logging, we log out ERROR, WARNING, INFO and DEBUG. the default value for our logger is INFO. we create the logger object in the primary setup of the tests, and pass it down to each object created, so all our logs go to the same logger.

so far when we are developing a new feature or test, we are working in DEBUG mode locally, and change it back to INFO when submitting new code to our SVN, but i am trying to add option to change logging level using the CLI, but i haven't found anything easy to implement. I've considered using Fixtures, but from what i understand those are only for the tests themselves, and not for the setup/tear-down phases, and the log is created regard less of the tests. any hack or idea on how to add a Pytest option to the CLI command to support changing logging level?

回答1:

Combining pytest commandline options and the python loglevel from commandline example you can do the following:

Add the following to conftest.py:

import pytest
import logging


def pytest_addoption(parser):
    parser.addoption(
        "--log", action="store", default="WARNING", help="set logging level"
    )


@pytest.fixture
def logger():
    loglevel = pytest.config.getoption("--log")
    logger = logging.getLogger(__name__)

    numeric_level = getattr(
        logging,
        loglevel.upper(),
        None
    )
    if not isinstance(numeric_level, int):
        raise ValueError('Invalid log level: %s' % loglevel)

    logger.setLevel(numeric_level)
    return logger

and then request the logger fixture in your tests

def test_bla(logger):
    assert True
    logger.info("True is True")

Then run pytest like

py.test --log INFO

to set the log level to INFO.

回答2:

Try --log-cli-level=INFO

like:

pytest -vv -s --log-cli-level=INFO --log-cli-format="%(asctime)s [%(levelname)8s] %(message)s (%(filename)s:%(lineno)s)" --log-cli-date-format="%Y-%m-%d %H:%M:%S" ./test_file.py