Question on logger.catch()

Hi! Is there a way to implement @logger.catch as a decorator for all tests, predeterming it in conftest.py in order to not to mark every my test? What i’m trying to do whit it now is:

# conftest.py

@pytest.fixture(autouse=True)
def write_logs(request):
    # put logs in tests/logs
    log_path = Path("Tests") / "logs"

    # tidy logs in subdirectories based on test module and class names
    module = request.module
    class_ = request.cls
    name = request.node.name + ".log"

    if module:
        log_path /= module.__name__.replace("tests.", "")
    if class_:
        log_path /= class_.__name__

    log_path.mkdir(parents=True, exist_ok=True)

    # append last part of the name
    log_path /= name

    # enable the logger
    logger.remove()
    logger.configure(handlers=[{"sink": log_path, "level": "TRACE", "mode": "w"}])
    logger.enable("my_package")

def pytest_configure(config):
    # register an additional marker
    config.addinivalue_line(
        "markers", "log_catcher: mark tests which we want to log"
    )


def pytest_collection_modifyitems(items):
    for item in items:
        item.add_marker('log_catcher')


def pytest_runtest_setup(item):
    if item.iter_markers(name="log_catcher"):
        logger.catch(reraise=True)

# test.py
class TestFirstSuite(unittest.TestCase):

    def test_01_First(self):
        assert 1+1 == 3

    def test_02_First(self):
        print('test_02_First executed')

    def test_03_First(self):
        print('test_03_First executed')

but i get no logs from this in my file.log

From debugging I see that pytest collector actually “marks” all tests, but I guess this cannot work because of the incorrect usage of “logger.catch” function or just custom decorators cant work like this if I use @logger.catch right before the def_test() then everything is working ok, but I want to mark all my tests with it and at the same time I wouldnt like to mark each test. I need “fixture” which will mark all tests automatically with this decorator during test collection. Could you help me please find the way out of this problem? What am i doing wrong and what i have to do?

[Delgan]

Hi @PistonY.

There is inevitably a small performance penalty, at least with CPython interpreter. In the case of logger.catch() being used as a decorator, there is one more frame and function call due to the nested method. Also, the logger.catch() is implemented using context manager which has a cost. Apart from that, it’s a basic try / except block.

Overall, the cost on performances should negligible. If the part of your code is really critical, you can use instead try / except and then logger.exception().

[PistonY]

Thanks @Delgan .