Nuxt/docs/content/3.docs/2.directory-structure/13.server.md

---
icon: IconDirectory
title: server
head.title: Server directory
---

# Server directory

Nuxt uses the `server/` directory to create any backend logic for your application. It supports HMR and powerful features.

The `server/` directory contains API endpoints and server middleware for your project.

## API Routes

Nuxt will automatically read in any files in the `~/server/api` directory to create API endpoints.

Each file should export a default function that handles API requests. It can return a promise or JSON data directly (or use `res.end()`).

### Examples

#### Hello world

```js [server/api/hello.ts]
export default (req, res) => 'Hello World'
```

See the result on <http://localhost:3000/api/hello>.

#### Async function

```js [server/api/async.ts]
export default async (req, res) => {
  await someAsyncFunction()

  return {
    someData: true
  }
}
```

**Example:** Using Node.js style

```ts [server/api/node.ts]
import type { IncomingMessage, ServerResponse } from 'http'

export default async (req: IncomingMessage, res: ServerResponse) => {
  res.statusCode = 200
  res.end('Works!')
}
```

#### Accessing req data

```js
import { useBody, useCookies, useQuery } from 'h3'

export default async (req, res) => {
  const query = useQuery(req)
  const body = await useBody(req) // only for POST | PUT | PATCH | DELETE requests
  const cookies = useCookies(req)
  
  return { query, body, cookies }
}
```

Learn more about [h3 methods](https://www.jsdocs.io/package/h3#package-index-functions).

## Server Middleware

Nuxt will automatically read in any files in the `~/server/middleware` to create server middleware for your project.

These files will be run on every request, unlike [API routes](#api-routes) that are mapped to their own routes. This is typically so you can add a common header to all responses, log responses or modify the incoming request object for later use in the request chain.

Each file should export a default function that will handle a request.

```js
export default async (req, res) => {
  req.someValue = true
}
```

There is nothing different about the `req`/`res` objects, so typing them is straightforward.

```ts
import type { IncomingMessage, ServerResponse } from 'http'

export default async (req: IncomingMessage, res: ServerResponse) => {
  req.someValue = true
}
```

To pass the request deeper into the application, you can `return` inside the function:

```js
export default async (req, res) => {
  const isNotHandledByThisMiddleware = req.url.includes('/some-unhandled-url-path/')
  if(isNotHandledByThisMiddleware) {
    return
  }

  // Actual logic here
}
```

::alert{type=info icon=🔎}
Find more information about custom middleware in the documentation for [nuxt.config.js](/docs/directory-structure/nuxt.config#servermiddleware)
::