# log-process-errors
> Show some ❤️ to process errors
Latest version **12.0.1** (published 2025-03-29) · Apache-2.0 license · 0 weekly downloads
## Install
```sh
npm install log-process-errors
pnpm add log-process-errors
yarn add log-process-errors
bun add log-process-errors
```
## Health
**Score 55/100 (C)** — status: stable.
Positive: has types; esm support; no vulnerabilities; high maintenance score; high quality score.
Warnings: low downloads.
Negative: stale.
## Facts
| | |
|---|---|
| Version | 12.0.1 |
| Published | 2025-03-29 |
| First published | 2018-10-16 |
| Weekly downloads | 0 |
| License | Apache-2.0 |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Node | >=18.18.0 |
| Dependencies | 4 |
| Unpacked size | 28.2 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 469 |
| Author | ehmicky |
| Maintainers | ehmicky |
| Keywords | code-quality, debugging, error, error-handler, error-handling, exception, handler, handling, javascript, library, logging, monitoring, nodejs, process, promise, test, testing, typescript, uncaught, uncaught-exceptions |
## Links
- npm: https://www.npmjs.com/package/log-process-errors
- Repository: https://github.com/ehmicky/log-process-errors
- Homepage: https://www.github.com/ehmicky/log-process-errors
- Issues: https://github.com/ehmicky/log-process-errors/issues
- npm.io page: https://npm.io/package/log-process-errors
## Dependencies (4)
- [is-plain-obj](https://npm.io/package/is-plain-obj.md) ^4.1.0
- [is-error-instance](https://npm.io/package/is-error-instance.md) ^3.0.1
- [set-error-message](https://npm.io/package/set-error-message.md) ^3.0.1
- [normalize-exception](https://npm.io/package/normalize-exception.md) ^4.0.1
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## Recent versions
- 12.0.1 (latest) — 2025-03-29
- 12.0.0 — 2023-10-28
- 11.0.1 — 2023-05-14
- 11.0.0 — 2023-05-13
- 10.2.0 — 2022-11-11
- 10.1.1 — 2022-10-16
- 10.1.0 — 2022-10-13
- 10.0.0 — 2022-10-11
- 9.4.0 — 2022-10-08
- 9.3.0 — 2022-08-17
- 9.2.0 — 2022-08-16
- 9.1.0 — 2022-07-17
- 9.0.0 — 2022-05-09
- 8.0.0 — 2022-02-18
- 7.0.1 — 2021-06-22
- … 72 more at https://npm.io/package/log-process-errors/versions
## README
[](https://www.npmjs.com/package/log-process-errors)
[](/src/main.d.ts)
[](https://codecov.io/gh/ehmicky/log-process-errors)
[](https://fosstodon.org/@ehmicky)
[](https://medium.com/@ehmicky)
[📰 Medium article.](https://medium.com/@ehmicky/node-js-process-errors-are-broken-193980f0a77b)
Show some ❤️ to Node.js process errors.
This improves process errors:
[uncaught](https://nodejs.org/api/process.html#process_event_uncaughtexception)
exceptions,
[unhandled](https://nodejs.org/api/process.html#process_event_unhandledrejection)
promises, promises
[handled too late](https://nodejs.org/api/process.html#process_event_rejectionhandled)
and [warnings](https://nodejs.org/api/process.html#process_event_warning).
# Features
- Stack traces for warnings and
[`rejectionHandled`](https://nodejs.org/api/process.html#process_event_rejectionhandled)
- [Single event handler](#onerror) for all process errors
- Ignore [duplicate](#onerror) process errors
- [Normalize](#error) invalid errors
- [Process exit](#exit) is graceful and can be prevented
# Install
Production code (e.g. a server) can install this either as a production or
development dependency:
```bash
npm install log-process-errors
```
However, libraries should install this as a development dependency:
```bash
npm install -D log-process-errors
```
This is because logging is modified globally and libraries users might not
expect this side-effect. Also, this might lead to conflicts between libraries.
This package works in Node.js >=18.18.0.
This is an ES module. It must be loaded using
[an `import` or `import()` statement](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c),
not `require()`. If TypeScript is used, it must be configured to
[output ES modules](https://www.typescriptlang.org/docs/handbook/esm-node.html),
not CommonJS.
# API
## logProcessErrors(options?)
[`options`](#options) `object?`\
_Return value_: `() => void`
Start handling process errors.
```js
import logProcessErrors from 'log-process-errors'
logProcessErrors(options)
```
The return value restores Node.js default behavior.
```js
const restore = logProcessErrors(options)
restore()
```
## Options
### exit
_Type_: `boolean`
Whether to exit the process on
[uncaught exceptions](https://nodejs.org/api/process.html#process_event_uncaughtexception)
or
[unhandled promises](https://nodejs.org/api/process.html#process_event_unhandledrejection).
This is `false` by default if other libraries are listening to those events, so
they can perform the exit instead. Otherwise, this is `true`.
If some tasks are still ongoing, the exit waits for them to complete up to 3
seconds.
### onError
_Type_: `(error, event) => Promise | void`\
_Default_: `console.error(error)`
Function called once per process error. Duplicate process errors are ignored.
```js
// Log process errors with Winston instead
logProcessErrors({
onError: (error, event) => {
winstonLogger.error(error.stack)
},
})
```
#### error
_Type_: `Error`
The process error. This is guaranteed to be a
[normalized](https://github.com/ehmicky/normalize-exception) error instance. A
short description of the [event](#event) is also appended to its message.
#### event
_Type_: `Event`
Process event name among:
[`'uncaughtException'`](https://nodejs.org/api/process.html#process_event_uncaughtexception),
[`'unhandledRejection'`](https://nodejs.org/api/process.html#process_event_unhandledrejection),
[`'rejectionHandled'`](https://nodejs.org/api/process.html#process_event_rejectionhandled),
[`'warning'`](https://nodejs.org/api/process.html#process_event_warning).
# Related projects
- [`modern-errors`](https://github.com/ehmicky/modern-errors): Handle errors in
a simple, stable, consistent way
- [`modern-errors-process`](https://github.com/ehmicky/modern-errors-process):
Handle process errors
- [`error-custom-class`](https://github.com/ehmicky/error-custom-class): Create
one error class
- [`error-class-utils`](https://github.com/ehmicky/error-class-utils): Utilities
to properly create error classes
- [`error-serializer`](https://github.com/ehmicky/error-serializer): Convert
errors to/from plain objects
- [`normalize-exception`](https://github.com/ehmicky/normalize-exception):
Normalize exceptions/errors
- [`is-error-instance`](https://github.com/ehmicky/is-error-instance): Check if
a value is an `Error` instance
- [`merge-error-cause`](https://github.com/ehmicky/merge-error-cause): Merge an
error with its `cause`
- [`set-error-class`](https://github.com/ehmicky/set-error-class): Properly
update an error's class
- [`set-error-message`](https://github.com/ehmicky/set-error-message): Properly
update an error's message
- [`wrap-error-message`](https://github.com/ehmicky/wrap-error-message):
Properly wrap an error's message
- [`set-error-props`](https://github.com/ehmicky/set-error-props): Properly
update an error's properties
- [`set-error-stack`](https://github.com/ehmicky/set-error-stack): Properly
update an error's stack
- [`error-cause-polyfill`](https://github.com/ehmicky/error-cause-polyfill):
Polyfill `error.cause`
- [`handle-cli-error`](https://github.com/ehmicky/handle-cli-error): 💣 Error
handler for CLI applications 💥
- [`error-http-response`](https://github.com/ehmicky/error-http-response):
Create HTTP error responses
- [`winston-error-format`](https://github.com/ehmicky/winston-error-format): Log
errors with Winston
# Support
For any question, _don't hesitate_ to [submit an issue on GitHub](../../issues).
Everyone is welcome regardless of personal background. We enforce a
[Code of conduct](CODE_OF_CONDUCT.md) in order to promote a positive and
inclusive environment.
# Contributing
This project was made with ❤️. The simplest way to give back is by starring and
sharing it online.
If the documentation is unclear or has a typo, please click on the page's `Edit`
button (pencil icon) and suggest a correction.
If you would like to help us fix a bug or add a new feature, please check our
[guidelines](CONTRIBUTING.md). Pull requests are welcome!
Thanks go to our wonderful contributors:
---
_Source: https://npm.io/package/log-process-errors · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._
