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# Api Routes

Simple API routes inside Next.js app like for form input

Just create a **function** inside the `pages/api` directory that has the following format:

/pages/api/hello.js

```ts
import type { NextApiRequest, NextApiResponse } from 'next'
 
type ResponseData = {
  message: string
}
 
export default function handler(
  req: NextApiRequest,
  res: NextApiResponse<ResponseData>
) {
  res.status(200).json({ message: 'Hello from Next.js!' })
}
```

<http://localhost:3000/api/hello>

They can be deployed as Serverless Functions (also known as Lambdas).

* `req` is an instance of [http.IncomingMessage](https://nodejs.org/api/http.html#http_class_http_incomingmessage), plus some pre-built middlewares you can see [here](https://nextjs.org/docs/api-routes/api-middlewares).
* `res` is an instance of [http.ServerResponse](https://nodejs.org/api/http.html#http_class_http_serverresponse), plus some helper functions you can see [here](https://nextjs.org/docs/api-routes/response-helpers).

**Do Not Fetch an API Route from `getStaticProps` or `getStaticPaths`**, instead just run the code in them since it runs serverside anyway

[Dynamic Api Routes](https://nextjs.org/docs/api-routes/dynamic-api-routes)