@fastify/error

@fastify/error

A small utility, used by Fastify itself, for generating consistent error objects across your codebase and plugins.

Install

npm i @fastify/error

Usage

The module exports a function that you can use for consistent error objects, it takes 4 parameters:

createError(code, message [, statusCode [, Base [, captureStackTrace]]])

• code (string, required) - The error code, you can access it later with error.code. For consistency, we recommend prefixing plugin error codes with FST_
• message (string, required) - The error message. You can also use interpolated strings for formatting the message.
• statusCode (number, optional) - The status code that Fastify will use if the error is sent via HTTP.
• Base (ErrorConstructor, optional) - The base error object that will be used. (eg TypeError, RangeError)
• captureStackTrace (boolean, optional) - Whether to capture the stack trace or not.

const createError = require('@fastify/error')
const CustomError = createError('ERROR_CODE', 'Hello')
console.log(new CustomError()) // error.message => 'Hello'

How to use an interpolated string:

const createError = require('@fastify/error')
const CustomError = createError('ERROR_CODE', 'Hello %s')
console.log(new CustomError('world')) // error.message => 'Hello world'

How to add cause:

const createError = require('@fastify/error')
const CustomError = createError('ERROR_CODE', 'Hello %s')
console.log(new CustomError('world', {cause: new Error('cause')}))
// error.message => 'Hello world'
// error.cause => Error('cause')

TypeScript

It is possible to limit your error constructor with a generic type using TypeScript:

const CustomError = createError<[string]>('ERROR_CODE', 'Hello %s')
new CustomError('world')
//@ts-expect-error
new CustomError(1)

License

Licensed under MIT.

Similar packages

Other packages similar to @fastify/error

http-errors

Similar to @fastify/error, http-errors is a package for generating HTTP errors for Node.js web applications. While @fastify/error is tailored for Fastify applications, http-errors is more generic and can be used with any Node.js web framework.

boom

Boom provides a set of utilities for returning HTTP errors. It offers more predefined errors compared to @fastify/error. However, @fastify/error allows for more customization in defining error constructors with default messages and status codes.