handle-rejection

handle-rejection

💀 Handle unhandled rejections

Built in single handlers

require('handle-rejection').console(); // console.error(error)

Name	Details
console	console.error
exit	process.exit
throw	throws error
collect	Prints all errors before process exists

Combine handlers

require('handle-rejection')(
	'console',
	'collect'
);

This one is a good combination for long test suits (see below) †

Custom handlers

const errobj = require('errobj');

require('handle-rejection')(
	error => fetch(
		'/report-error',
		{
			method: 'POST',
			body: JSON.stringify(errobj(error))
		}
	)
);

Combined handlers: built in and custom

require('handle-rejection')(
	error => Raven.captureException(error) // custom
	'exit', // built in
);

---

† Example for a combination of "console" and "collect" in a testing environment

> mocha

  some function
    ✓ Should be okay
TypeError: Cannot read property 'ok' of undefined
    at ok (/workspace/package/spec.js:21:11)
    at tryCatch (/workspace/package/node_modules/regenerator-runtime/runtime.js:45:40)
    at Generator.invoke [as _invoke] (/workspace/package/node_modules/regenerator-runtime/runtime.js:271:22)
    at Generator.prototype.(anonymous function) [as next] (/workspace/package/node_modules/regenerator-runtime/runtime.js:97:21)
    at asyncGeneratorStep (/workspace/package/spec.js:14:103)
    at _next (/workspace/package/spec.js:16:194)
    at process._tickCallback (internal/process/next_tick.js:68:7)

  some other function
    ✓ Should success
    ✓ Should also success
    ✓ Should really work

  another bulk of tests
    ✓ Should be fine
    ✓ Should pass the test

  6 passing (110ms)

╭─────────────────────────────╮
│ Unhandled Rejection Summary │
╰─────────────────────────────╯

❗️ Rejection 1:
TypeError: Cannot read property 'ok' of undefined
    at ok (/workspace/package/spec.js:21:11)
    at tryCatch (/workspace/package/node_modules/regenerator-runtime/runtime.js:45:40)
    at Generator.invoke [as _invoke] (/workspace/package/node_modules/regenerator-runtime/runtime.js:271:22)
    at Generator.prototype.(anonymous function) [as next] (/workspace/package/node_modules/regenerator-runtime/runtime.js:97:21)
    at asyncGeneratorStep (/workspace/package/spec.js:14:103)
    at _next (/workspace/package/spec.js:16:194)
    at process._tickCallback (internal/process/next_tick.js:68:7)