
Yet another POSIX signal handler.
Features
- Ensures provided functions are called before any other event listeners and are run concurrently, minimizing shutdown time.
- Works with any combination of synchronous and asynchronous functions.
- Ensures a clean exit if all functions resolve/return.
- Exits with an error if any functions reject/throw.
- Ensures processes exit cleanly, even when they have asynchronous shut-down functions and the Node debugger is in use. (See this issue)
Install
npm i @darkobits/adeiu
Use
Adeiu accepts an asynchronous or synchronous handler function and returns a function that can be invoked to unregister the handler. By default, the handler will be registered to respond to the following signals:
SIGINT
SIGQUIT
SIGTERM
SIGUSR2
import adeiu from '@darkobits/adeiu';
// Register a callback.
const annuler = adeiu(async signal => {
console.log(`Hey, we got ${signal}. Exiting...`);
await someAsyncStuff();
console.log('All done!');
});
// Un-register the callback.
annuler();
Customizing Signals
Usually, responding to signals dynamically can be accomplished by inspecting the signal
argument
passed to your callback. However, if it is important that listeners are only installed on a particular
signal, you may optionally provide a custom array of signals to assign a callback to.
import adeiu from '@darkobits/adeiu';
// Register callback that will _only_ be invoked on SIGINT.
adeiu(() => {
// SIGINT cleanup tasks.
}, ['SIGINT']);
import adeiu, { SIGNALS } from '@darkobits/adeiu';
// Register callback with the default signals and SIGUSR1.
adeiu(() => {
// Custom cleanup tasks.
}, [...SIGNALS, 'SIGUSR1']);
