README.md

modern-errors plugin to handle errors in CLI modules.

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

Features

• 🖍️ Pretty colors, icons and header
• 🚒 Graceful exit
• ⛑️ Normalize invalid errors
• 🔕 Log verbosity: message, stack, properties
• 🚨 Custom exit code
• 💥 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 error.exit() in the CLI's top-level error handler.

const cliMain = function () {
  try {
    // ...
  } catch (error) {
    // Ensure `error` is a `BaseError` instance
    const normalizedError = BaseError.normalize(error)
    // Logs `error` then exits the process
    normalizedError.exit()
  }
}

cliMain()

Install

npm install modern-errors-cli

This package requires Node.js >=14.18.0. It is an ES module and must be loaded using an import or import() statement, not require().

API

modernErrorsCli

Type: Plugin

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

error.exit()

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.

Note: when passing invalid options, the exit code is always 125.

📕 stack

Type: boolean
Default: true

Whether to log the error's stack trace.

📢 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

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 error.exit() call

error.exit(...args, { ...options })

Related projects

• handle-cli-error: 💣 Error handler for CLI applications 💥
• modern-errors: Handle errors like it's 2022 🔮
• 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

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!