next.js/errors/next-prerender-sync-request.mdx

---
title: Cannot access Request information synchronously in route.js without awaiting connection first
---

## Why This Error Occurred

When `cacheComponents` is enabled Next.js treats most access to Request information as explicitly dynamic. However routes have a Request object and you can read values like the current pathname from that object synchronously. If you need to access Request information in a route handler you should first call `await connection()` to inform Next.js that everything after this point is explicitly dynamic.

This is only needed in `GET` handlers because `GET` is the only handler Next.js will attempt to prerender.

## Possible Ways to Fix It

Look for access of the Request object in your route.js and add `await connection()` before you access any properties of the Request.

Before:

```jsx filename="app/.../route.js"
export default function GET(request) {
  const requestHeaders = request.headers
  return ...
}
```

After:

```jsx filename="app/.../route.js"
import { connection } from 'next/server'

export default async function GET(request) {
  await connection()
  const requestHeaders = request.headers
  return ...
}
```

It is unexpected that you would run the codemod and not successfully convert all instances of `params` and `searchParams` to async or have a marker string to help you locate unconverted cases. If you do find yourself in this situation please report this to [Next.js on Github](https://github.com/vercel/next.js/issues).

## Useful Links

- [`connection` function](/docs/app/api-reference/functions/connection)
- [`route.js` file convention](/docs/app/api-reference/file-conventions/route)