modern-errors plugin to handle errors in CLI modules.

This adds BaseError.exit(error) which logs error then exits the process.

Features

• 🖍️ Pretty colors, icons and header
• 🚒 Graceful exit
• ⛑️ Normalize invalid errors
• 🔕 Log verbosity: message, stack, nested errors, properties
• 🚨 Custom exit code and log function
• 💥 Exception-safe

Screenshot

Example

Adding the plugin to modern-errors.

import ModernError from 'modern-errors'

import modernErrorsCli from 'modern-errors-cli'

export const BaseError = ModernError.subclass('BaseError', {
  plugins: [modernErrorsCli],
})
// ...

Calling BaseError.exit(error) in the CLI's top-level error handler.

const cliMain = () => {
  try {
    // ...
  } catch (error) {
    // Logs `error` then exits the process
    BaseError.exit(error)
  }
}

cliMain()

Install

npm install modern-errors-cli

This package requires Node.js >=18.18.0.

This is an ES module. It must be loaded using an import or import() statement, not require(). If TypeScript is used, it must be configured to output ES modules, not CommonJS.

API

modernErrorsCli

Type: Plugin

Plugin object to pass to the plugins option of ErrorClass.subclass().

BaseError.exit(error)

error: any

Logs error on the console (stderr) then exits the process.

This never throws. Invalid errors are silently normalized.

Options

Type: object

🚨 exitCode

Type: integer
Default: 1

Process exit code.

We recommend values between 1 and 124 because the following exit codes have some special meaning:

• 0: success
• 125: invalid options
• 126 to 255: used by shells like Bash

📕 stack

Type: boolean
Default: true

Whether to log the error's stack trace.

🪏 cause

Type: boolean
Default: true

Whether to show aggregate errors.

📢 props

Type: boolean
Default: true

Whether to log the error's additional properties.

🔕 silent

Type: boolean
Default: false

Exits the process without logging anything on the console.

🖍️ colors

Type: boolean
Default: true in terminals, false otherwise

Whether to colorize the error's message, stack trace and additional properties.

Quoted strings in the error's message are printed in bold (for "..." and '...') and in italic (for `...`).

❌ icon

Type: string
Default: 'cross'

Icon prepended to the error's name. The available values are listed here. Can be disabled by passing an empty string.

💄 header

Type: string
Default: 'red bold'

Color/style of the error's icon and name. The available values are listed here. Several styles can be specified by using spaces. Can be disabled by passing an empty string.

🚒 timeout

Type: integer (in milliseconds)
Default: 5000 (5 seconds)

The process exits gracefully: it waits for any ongoing tasks (callbacks, promises, etc.) to complete, up to a specific timeout.

Special values:

• 0: Exits right away, without waiting for ongoing tasks
• Number.POSITIVE_INFINITY: Waits for ongoing tasks forever, without timing out

📜 log

Type: (string) => void
Default: console.error

Function used to print the error message.

Configuration

Options can apply to (in priority order):

• Any error: second argument to ModernError.subclass()

export const BaseError = ModernError.subclass('BaseError', {
  plugins: [modernErrorsCli],
  cli: options,
})

• Any error of a specific class (and its subclasses): second argument to ErrorClass.subclass()

export const InputError = BaseError.subclass('InputError', { cli: options })

• A specific error: second argument to new ErrorClass()

throw new InputError('...', { cli: options })

• A specific BaseError.exit(error) call

BaseError.exit(error, options)

Related projects

• handle-cli-error: 💣 Error handler for CLI applications 💥
• beautiful-error: Prettify error messages and stacks
• modern-errors: Handle errors in a simple, stable, consistent way
• modern-errors-beautiful: Prettify errors messages and stacks
• modern-errors-process: Handle process errors
• modern-errors-bugs: Print where to report bugs
• modern-errors-serialize: Serialize/parse errors
• modern-errors-clean: Clean stack traces
• modern-errors-http: Create HTTP error responses
• modern-errors-winston: Log errors with Winston
• modern-errors-switch: Execute class-specific logic

Support

For any question, don't hesitate to submit an issue on GitHub.

Everyone is welcome regardless of personal background. We enforce a Code of conduct 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. Pull requests are welcome!