text: const fs = require("fs");
  const http = require("http");
  const map = require("through2-map");
  
  let port = process.argv[2];
  const server = http
    .createServer((req, res) => {
      res.writeHead(200, { "content-type": "text/plain" });
      if (req.method === "POST") {
        req.pipe(map((chunk) => {
            return chunk.toString().toUpperCase();
        })).pipe(res);
      } else {
          res.end("send me a POST\n")
      }
    })
    .listen(port);
  