Anatomy of an HTTP Transaction in nodejs

httpAnatomyInNode.js

/**
 * credit: https://nodejs.org/en/docs/guides/anatomy-of-an-http-transaction/ 
 */
const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

var server = http.createServer();
server.on('request',(req, res) => {



    if(req.method === 'POST' && req.url === '/echo'){
        const { method, url, headers, rawHeaders } = req;
        let body = [];
        req.on('error',(err) => {
            console.error(err.stack);
            res.statusCode = 400;
            res.end();
        }).on('data', (chunk) => {
            body.push(chunk);
        }).on('end', () => {
            body = Buffer.concat(body).toString();
            res.statusCode = 200;
            res.setHeader('Content-Type','application/json');
            res.write(JSON.stringify({ body, url, method, headers, rawHeaders,}));
            res.end();
        });
    } else {
        res.statusCode = 400;
        res.end();
    }    
}).listen(port, hostname, () => console.log(`Server running at http://${hostname}:${port}`));