test.js

import { serve, Response } from 'some-http-lib'

serve(3000, async ({ request }) => {
  const body = JSON.stringify({ hello: 'world' });
  return new Response(body, {
    status: 200,
    headers: new Headers({
      'content-type': 'application/json'
    })
  });
});

// middleware
function log (handler) {
  return async ({ request, ...props }) => {
    const start = Date.now();
    const response = await handler({ request, ...props });
    const end = Date.now();
    console.log(`Request: ${request.method} ${request.url.pathname} (${end - start}ms)`)
    return response;
  };
}

// poor man's router
function route (routes) {
  return ({ request, ...props }) => {
    const handler = routes[request.url.path] || () => new Response(null, { status: 404 });
    return handler({ request, ...props });
  }
}

serve(3000, log(route({
  '/hello': async () => new Response('world'),
  '/world': async () => Response.redirect('/hello'),
  '/echo': async ({ request }) => new Response(request.url.path)
})));