@rowanmanning/render-error-page NPM

@rowanmanning/render-error-page

Render nice error pages with Express.

Requirements

This library requires the following to run:

Node.js 20+

Usage

Install with npm:

npm install @rowanmanning/render-error-page

Load the library into your code with a require call:

const { renderErrorPage } = require('@rowanmanning/render-error-page');

Create the error rendering middleware and add it as the very last one to your Express app (more details available in this Express guide):

const express = require('express');
const { renderErrorPage } = require('@rowanmanning/render-error-page');

const app = express();

app.get('/', (request, response, next) => {
    next(new Error('Oops'));
});

// Your error page!
app.use(renderErrorPage());

renderErrorPage relies on the Express built-in rendering method: response.render. You'll need to create an error view in your Express application. Where and how you do this depends on what your view rendering setup is. Normally it'll be a file like:

views/error.html

Replace .html above with the correct file extension for your views. Once you've done this, you can access the following view data:

error.code: the value of the code property of the error, if present
error.message: the actual error message
error.name: the value of the name property of the error, e.g. Error or TypeError
error.stack: the full error stack (if made available based on options)
error.status: the HTTP status code of the error (taken from the original error's statusCode or status properties)
error.statusCode: alias of error.status
error.statusMessage: the HTTP status message which corresponds to error.status, e.g. an error status of 404 would result in Not Found

An example in Handlebars:

<h1>Error {{error.statusCode}}</h1>
<p>{{error.message}}</p>
{{#if error.stack}}
    <pre>{{error.stack}}</pre>
{{/if}}

If your template cannot be rendered for some reason, then a basic fallback template will be used instead.

Options

You can configure the middleware using a few different options:

app.use(renderErrorPage({
    exampleOption: true
}));

The available options are:

errorView: the name of the view to render when an error occurs, relative to the Express views directory. Defaults to "error"
includeErrorStack: a boolean indicating whether to include the error stack in the output. Defaults to false if the NODE_ENV environment variable is set to "production", or true otherwise

Migration

A new major version of this project is released if breaking changes are introduced. We maintain a migration guide to help users migrate between these versions.