import React from 'react' import Link from 'next/link' import { useRouter } from 'next/router' export async function getServerSideProps({ query: { port } }) { if (!port) { throw new Error('port required') } return { props: { port } } } export default function Page({ port }) { const router = useRouter() return ( <> http://localhost:{port} {router.basePath}/something-else ) }