astro/packages/integrations/node/README.md

@astrojs/node 🔲

This adapter allows Astro to deploy your SSR site to Node targets.

• Why Astro Node
• Installation
• Usage
• Configuration
• Troubleshooting
• Contributing
• Changelog

Why Astro Node

If you're using Astro as a static site builder—its behavior out of the box—you don't need an adapter.

If you wish to use server-side rendering (SSR), Astro requires an adapter that matches your deployment runtime.

Node is a JavaScript runtime for server-side code. Frameworks like Express are built on top of it and make it easier to write server applications in Node. This adapter provides access to Node's API and creates a script to run your Astro project that can be utilized in Node applications.

Installation

Add the Node adapter to enable SSR in your Astro project with the following astro add command. This will install the adapter and make the appropriate changes to your astro.config.mjs file in one step.

npx astro add node

If you prefer to install the adapter manually instead, complete the following two steps:

1. Install the Node adapter to your project’s dependencies using your preferred package manager. If you’re using npm or aren’t sure, run this in the terminal:

     npm install @astrojs/node
   

2. Add two new lines to your astro.config.mjs project configuration file.

   import { defineConfig } from 'astro/config';
   import netlify from '@astrojs/node';
   
   export default defineConfig({
     output: 'server',
     adapter: node(),
   });
   

Usage

After performing a build there will be a dist/server/entry.mjs module that exposes a handler function. This works like a middleware function: it can handle incoming requests and respond accordingly.

Using a middleware framework

You can use this handler with any framework that supports the Node request and response objects.

For example, with Express:

import express from 'express';
import { handler as ssrHandler } from './dist/server/entry.mjs';

const app = express();
app.use(express.static('dist/client/'))
app.use(ssrHandler);

app.listen(8080);

Using http

This output script does not require you use Express and can work with even the built-in http and https node modules. The handler does follow the convention calling an error function when either

• A route is not found for the request.
• There was an error rendering.

You can use these to implement your own 404 behavior like so:

import http from 'http';
import { handler as ssrHandler } from './dist/server/entry.mjs';

http.createServer(function(req, res) {
  ssrHandler(req, res, err => {
    if(err) {
      res.writeHead(500);
      res.end(err.toString());
    } else {
      // Serve your static assets here maybe?
      // 404?
      res.writeHead(404);
      res.end();
    }
  });
}).listen(8080);

Configuration

This adapter does not expose any configuration options.

Troubleshooting

For help, check out the #support-threads channel on Discord. Our friendly Support Squad members are here to help!

You can also check our Astro Integration Documentation for more on integrations.

Contributing

This package is maintained by Astro's Core team. You're welcome to submit an issue or PR!

Changelog

See CHANGELOG.md for a history of changes to this integration.