http-errors - benhall/express-demo

HTTP errors are essential for handling and communicating various types of errors in web applications. One popular and versatile library for creating HTTP errors in Node.js projects is http-errors. In this guide, we’ll explain why you might want to use http-errors and provide an example of how to use it.

Description

http-errors is a Node.js module that makes it easy to create HTTP error objects for Express, Koa, Connect, and other frameworks. The latest version is 2.0.0, and it was last published 2 years ago. You can install it by running npm i http-errors. There are currently 3,558 other projects in the npm registry using http-errors.

Why Use HTTP Errors?

HTTP errors provide a standardized way to communicate errors to clients. They include a status code, a message, and sometimes custom properties. By using HTTP errors, you can make your API responses more consistent and easier to understand for developers and clients.

Installation and Example

First, install http-errors using npm:

$ npm install http-errors

Next, import the createError function from http-errors and use it to create HTTP errors in your Express application:

const express = require('express');
const createError = require('http-errors');

const app = express();

app.use((req, res, next) => {
if (!req.user) {
return next(createError(401, 'Please login to view this page.'));
}
next();
});

In this example, we use createError to create a 401 Unauthorized error when the user is not authenticated.

API

http-errors provides a simple API for creating HTTP errors. The following properties are available on each error object:

• expose: A boolean indicating whether the error message should be sent to the client. Defaults to false when the status code is 500 or higher.
• headers: An optional object of header names and values to be sent to the client.
• message: The error message, which should be kept short and all single line.
• status: The status code of the error.
• statusCode: The status code of the error, which defaults to 500.

You can create a new error object using the createError function:

const err = createError(404, 'This video does not exist!');

Or, you can extend an existing error object with createError:

fs.readFile('foo.txt', (err, buf) => {
if (err) {
if (err.code === 'ENOENT') {
const httpError = createError(404, err, { expose: false });
} else {
const httpError = createError(500, err);
}
}
});

Conclusion

http-errors is a simple and versatile library for creating HTTP errors in Node.js projects. It provides a consistent way to communicate errors to clients and makes it easy to create custom error messages and headers. To get started, install http-errors using npm and start creating HTTP errors in your application.