generic-errors

2.3.1 verified Fri May 01 auth: no javascript

Provides error constructors with common HTTP status codes as numeric properties, supporting both Node.js and browser usage. Current stable version is 2.3.1 (last updated with dependency security patches). Release cadence is ad-hoc with occasional minor updates. Key differentiators: includes a stack-trace ponyfill for Safari compatibility, does not pollute stack depth, and offers detection via BaseError.isGenericError even after JSON serialization. Over 40 error types from 4xx and 5xx families are available.

Common errors

error TypeError: errors.NotFound is not a constructor ↓

cause Using require on this package returns an object, not a class directly.

fix

Use: const errors = require('generic-errors'); const notFound = new errors.NotFound();

error import errors from 'generic-errors'; // SyntaxError: The requested module 'generic-errors' does not provide an export named 'default' ↓

cause No default ESM export.

fix

Use named import: import { NotFound, BadRequest } from 'generic-errors';

error Uncaught Error: toString() failed ↓

cause Instantiating without 'new' (e.g., errors.NotFound()).

fix

Always use 'new errors.NotFound()'.

Warnings

breaking v2.0.0 changed from exporting a single Error object to an object with named constructors. ↓

fix Update imports: const errors = require('generic-errors'); const notFound = new errors.NotFound();

deprecated Direct construction without 'new' is deprecated and may break in future. ↓

fix Always use 'new errors.SomeError()'.

gotcha Error properties may be lost if you serialize via JSON.stringify without custom toJSON. ↓

fix Use the built-in toJSON or implement your own serialization.

gotcha Some constructors like Teapot (418) are humorous but real HTTP status codes. ↓

fix Do not rely on all listed codes being widely recognized.

Install

npm install generic-errors

yarn add generic-errors

pnpm add generic-errors

Imports

NotFound

wrong

const { NotFound } = require('generic-errors');

correct

const errors = require('generic-errors');
const notFound = new errors.NotFound('message');

Named destructured import works in CommonJS, but module.exports = { ... } object; both patterns are valid.

BaseError

wrong

const BaseError = require('generic-errors').BaseError;

correct

import { BaseError } from 'generic-errors';

ESM import is available. The package does not have a default export.

BadRequest

wrong

import BadRequest from 'generic-errors';

correct

const { BadRequest } = require('generic-errors');

No default export; must use named import.

Quickstart

Shows importing, throwing, catching, custom properties, and serialized detection.

const errors = require('generic-errors');

try {
  throw new errors.NotFound('Resource not found');
} catch (err) {
  console.log(err.message);        // 'Resource not found'
  console.log(err.statusCode);     // 404
  console.log(err instanceof errors.BaseError); // true
}

// With additional properties
const err2 = new errors.Unprocessable({ message: 'Validation failed', fields: ['email'] });
console.log(err2.fields); // ['email']

// Detection after serialization
const serialized = JSON.parse(JSON.stringify(err2));
console.log(errors.BaseError.isGenericError(serialized)); // true