react-query/examples/react/nextjs-suspense-streaming/src/app/api/wait/route.ts

import { NextResponse } from 'next/server'

export async function GET(request: Request) {
  const { searchParams } = new URL(request.url)
  const wait = Number(searchParams.get('wait'))

  await new Promise((resolve) => setTimeout(resolve, wait))

  return NextResponse.json(`waited ${wait}ms`)
}