deno typescript server to provide ip external for client or visitor at server

ipr.ts

import {
  serve,
  type ConnInfo,
  type Handler,
  type ServeInit,
} from 'https://deno.land/std@0.144.0/http/server.ts';

function assertIsNetAddr(addr: Deno.Addr): asserts addr is Deno.NetAddr {
  if (!['tcp', 'udp'].includes(addr.transport)) {
    throw new Error('Not a valid network address');
  }
}

function addrRemote(connInfo: ConnInfo): Deno.NetAddr {
  assertIsNetAddr(connInfo.remoteAddr);
  return connInfo.remoteAddr;
}

const handler: Handler = (request, connInfo) => {
  const {hostname, port} = addrRemote(connInfo);
  const message = `from: ${hostname}\n`;
  console.log(message);
  return new Response(message);
};

const init: ServeInit = {port: 8080};

serve(handler, init);
console.log(`Serve on ${init.port}...\nCtrl + C to exit`);