Catch Without Log Or Rethrow (ARCH2165)

Key python.logging.catch-log-only · Severity info · Category logging

Handlers that catch and log an exception then continue normally without rethrowing may hide unrecoverable errors. Even though it is logged, execution proceeds as if the failure never happened.

Incorrect

def transfer(amount):
    try:
        bank.debit(amount)
    except BankError:
        logger.error("Debit failed")
    bank.credit(amount)

Correct

def transfer(amount):
    try:
        bank.debit(amount)
    except BankError:
        logger.exception("Debit failed")
        raise
    bank.credit(amount)

Fix

Do not log-and-swallow unrecoverable errors; log them and re-raise.