5. Utilities module

The util module provides some functions used by most fand modules.

It provides a terminate() function to make the daemon and its threads terminate cleanly. It provide a when_terminate() function decorator to add functions to call when terminate() is called, allowing custom cleanup from modules.

It also has a default signal handler, and a default argument parser.

5.1. Python API

5.1.1. terminate

fand.util.terminate(error: Optional[str] = None) → None

Function terminating the program

Sets the terminate flag (see terminating()), and does some cleanup (see when_terminate())

Parameters:error – Error message to print

5.1.2. sys_exit

fand.util.sys_exit() → NoReturn

Exit the program with the error from terminate() if any

5.1.3. terminating

fand.util.terminating() → bool

Returns True if the program is terminating, else False

5.1.4. when_terminate

fand.util.when_terminate(function: Callable, *args, **kwargs) → None

Add function to call when terminating

Parameters:

• function – Function to call
• args – Arguments to call the function with
• kwargs – Keyworded arguments to call the function with

5.1.5. sleep

fand.util.sleep(secs: float) → None

Sleep some time, stops if terminating

Parameters:secs – Number of seconds to sleep

5.1.6. default_signal_handler

fand.util.default_signal_handler(sig: int, _: Any) → None

Default signal handler

5.1.7. parse_args

fand.util.parse_args(parser: argparse.ArgumentParser) → argparse.Namespace

Add common arguments, parse arguments, set root logger verbosity

Parameters:parser – Argument parser to use