readable.js

const http   = require('http');
const BUFSIZ = 2048;

const handler = (req, res) => {
  req.on('readable', _ => {
    let chunk;
    while (null !== (chunk = req.read(BUFSIZ))) {
      res.write(chunk);
    }
  });
  req.on('end', () => {
    res.end();
  });
};
http.createServer(handler).listen(3001);