Bug: Cannot use Pytest's caplog fixture with non-preconfigured Logger

[amin-farjadi]

Expected Behaviour

Log records must appear in Pytest's caplog fixture since caplog is recommended for testing the logs in documentation.

Current Behaviour

When using a new Logger (non-preconfigured), the log record does not appear in caplog. However, messages logged by a child logger is captured by caplog.

Code snippet

The following tests must pass

import random
import string

import pytest
from _pytest.logging import LogCaptureHandler

from aws_lambda_powertools.logging.logger import Logger


@pytest.fixture
def service_name():
    chars = string.ascii_letters + string.digits
    return "".join(random.SystemRandom().choice(chars) for _ in range(15))


def test_non_preconfigured_logger_with_caplog(caplog, service_name):
    caplog.set_level("INFO")
    logger = Logger(service=service_name)
    logger.info("testing, testing...")
    pytest_handler_existence = any(isinstance(item, LogCaptureHandler) for item in logger._logger.parent.handlers)

    assert pytest_handler_existence is True
    assert len(caplog.records) == 1
    assert caplog.records[0].message == "testing, testing..."


def test_child_logger_with_caplog(caplog):
    caplog.set_level("INFO")
    logger = Logger(child=True)
    logger.info("testing, testing...")

    assert len(caplog.records) == 1

But, test_non_preconfigured_logger_with_caplog fails with:

>       assert len(caplog.records) == 1
E       assert 0 == 1
E        +  where 0 = len([])
E        +    where [] = <_pytest.logging.LogCaptureFixture object at 0x104e7c560>.records

Possible Solution

Add the following guard clause the _init_logger method of the Logger class (before checking if self.child:)

        if os.environ.get("PYTEST_CURRENT_TEST"):
            return

Steps to Reproduce

Copy and paste the above tests in tests/functional/logger/required_dependencies/test_logger.py file and run.

Powertools for AWS Lambda (Python) version

latest

AWS Lambda function runtime

3.12

Packaging format used

PyPi

Debugging logs

[leandrodamascena]

Hey @amin-farjadi let me take a look! Sorry for the late reply.