NodeJS web server routes GET/POST

router.node.js

'use strict';

const http = require('http');
const url = require('url');
const qs = require('querystring');
const port = 3000;

/*Pure nodejs way of routing, an obj to provide methods as main key then routes with deep clone*/

let routes = {
	'GET': {
		'/': (req, res) => {
			res.writeHead(200, {'Content-type': 'text/html'});
			res.end('<h1>This is a Home Route</h1><h3>You can try some of the below routes by changing URL</h3><ul><li>/about</li><li>/api/getinfo</li></ul><h4>For <strong>/api/getinfo</strong> route you can add query for example "/api/getinfo?color=red&color=blue"</h4>')
		},
		'/about': (req, res) => {
			res.writeHead(200, {'Content-type': 'text/html'});
			res.end('<h1>This is a About Route</h1>')
		},
		'/api/getinfo': (req, res) => {
			res.writeHead(200, {'Content-type': 'application/json'});
			res.end(JSON.stringify(req.queryParams));
		}
	},

	/*  For POST Methods, you require POSTMAN
  set form-urlencoded then set key & value as
  username & password in the body*/

	'POST': {
		'/api/login': (req, res) => {

	/*Body is to mimic a simple body-parser*/
			let body = '';
			req.on('data', data => {
				body += data;
	
	/*For image in binary form upload that exceeds 2mb 
	 destroy connections to stop file trfs, this will not crash server
   but if not connection is destroy only with writeHead, upload will continue */
        
				if(body.length > 2000000) {
					res.writeHead(413, {'Content-type': 'text/html'});
					res.end('<h3>Error: uploaded file size exceeds 2MB</h3>', 
						() => req.connection.destroy());
				}
			});

	/*Allow query string to serialize the body*/
			req.on('end', () => {
				let params = qs.parse(body);
				console.log('username: ',params['username']);
				console.log('password: ',params['password']);
				res.end();
			});
		}

	},
	'NA': (req, res) => {
		res.writeHead(404);
		res.end('Content not found!?')
	}
}

/*Similar to how express.router() 
 there will always be a METHOD follow by pathname*/

function router(req, res) {
	let BASE_URL = url.parse(req.url, true);
	console.log(req.params);
	let resolveRoute = routes[req.method][BASE_URL.pathname];
	if(resolveRoute != undefined){
		req.queryParams = BASE_URL.query;
		resolveRoute(req, res);
	} else {
		routes['NA'](req, res);
	}
}

/*create Server*/
http.createServer(router).listen(port, () => {
	console.log(`listening on ${port}`);
});