How to mark an exception as recoverable

To make an exception recoverable and prevent it from crashing the application, you can use the caqtus.types.recoverable_exceptions module.

If you control the code that raises the exception

If you have control over the exception you are raising, raise an exception that inherits from caqtus.types.recoverable_exceptions.RecoverableException.

The module caqtus.types.recoverable_exceptions defines common recoverable exceptions that you can use. If no recoverable exception fits your use case, you can create a new exception that inherits from caqtus.types.recoverable_exceptions.RecoverableException.

Examples:

from caqtus.types.recoverable_exceptions import InvalidValueError

def set_voltage(voltage):
    if voltage < 0:
        raise InvalidValueError('Voltage must be positive')
    else:
        # Do something with the voltage

from caqtus.types.recoverable_exceptions import RecoverableException

class MyCustomError(RecoverableException):
    pass

def my_function():
    raise MyCustomError('Something went wrong')

If you don’t control the code that raises the exception

If you don’t control the code that raises the exception, you can catch the exception and re-raise a recoverable exception with the original exception as the cause.

Example:

from caqtus.types.recoverable_exceptions import InvalidTypeError

def my_function():
    try:
        # Code that raises an exception
        ...
    except TypeError as e:
        raise InvalidTypeError('Something went wrong') from e