hard-rejection

What is hard-rejection?

The hard-rejection npm package is designed to ensure that unhandled promise rejections in Node.js applications are treated as hard errors, similar to throwing an exception. It is typically used during development to make sure that promise rejections do not go unnoticed.

What are hard-rejection's main functionalities?

Automatic handling of unhandled promise rejections

By simply requiring or importing 'hard-rejection/register', the package will automatically ensure that any unhandled promise rejections are treated as errors and will cause the Node.js process to exit with a non-zero exit code, making them more noticeable during development.

require('hard-rejection/register');
// or
import 'hard-rejection/register';

Other packages similar to hard-rejection

loud-rejection

Similar to hard-rejection, loud-rejection makes unhandled promise rejections loud by logging them to the console. However, it does not terminate the Node.js process.

why-is-node-running

While not directly related to promise rejections, why-is-node-running can be used to log out active handles that are keeping Node.js running, which can be useful for debugging unhandled rejections or other issues.

bluebird

Bluebird is a full-featured promise library that, among other things, can be configured to handle unhandled rejections in various ways. It is more comprehensive than hard-rejection, which has a more singular focus.

README

hard-rejection

Make unhandled promise rejections fail hard right away instead of the default silent fail

Promises fail silently if you don't attach a .catch() handler.

This module exits the process with an error message right away when an unhandled rejection is encountered.
Note: That might not be desirable as unhandled rejections can be handled at a future point in time, although not common. You've been warned.

Intended for top-level long-running processes like servers, but not in reusable modules.
For command-line apps and tests, see loud-rejection.

Install

$ npm install hard-rejection

Usage

const hardRejection = require('hard-rejection');
const promiseFunction = require('some-promise-fn');

// Install the handler
hardRejection();

promiseFunction();

Without this module it's more verbose and you might even miss some that will fail silently:

const promiseFunction = require('some-promise-fn');

function error(error) {
	console.error(error.stack);
	process.exit(1);
}

promiseFunction().catch(error);

Register script

Alternatively to the above, you may simply require hard-rejection/register and the handler will be automagically installed for you.

This is handy for ES2015 imports:

import 'hard-rejection/register';

API

hardRejection([log])

log

Type: Function
Default: console.error

Custom logging function to print the rejected promise. Receives the error stack.

Related

• loud-rejection - Make unhandled promise rejections fail loudly instead of the default silent fail
• More…

License

MIT © Sindre Sorhus