HTTP Server

Code

import { createServer } from "http";

const server = createServer(async (req, res) => {
  const url = new URL(req.url, "http://localhost");
  res.setHeader("Content-Type", "application/json");

  if (req.method === "GET" && url.pathname === "/api/users") {
    res.end(JSON.stringify([{ id: 1, name: "Alice" }]));
    return;
  }

  if (req.method === "POST" && url.pathname === "/api/users") {
    const body = await readBody(req);
    res.statusCode = 201;
    res.end(JSON.stringify({ created: body }));
    return;
  }

  res.statusCode = 404;
  res.end(JSON.stringify({ error: "Not found" }));
});

function readBody(req) {
  return new Promise(resolve => {
    let data = "";
    req.on("data", chunk => (data += chunk));
    req.on("end", () => resolve(JSON.parse(data || "{}")));
  });
}

server.listen(3000, () => console.log("listening on :3000"));

Explanation

createServer returns an HTTP server that invokes a callback for each request, with req and res streams for reading the body and writing the response. The URL constructor parses the request URL for routing, and a helper buffer reads the request body. For production apps, prefer a framework like Express or Fastify.

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