server.js

const http = require('http');
const fs = require('fs');
const path = require('path');

const port = 5000;

const server = http.createServer((req, res) => {
    
    let filePath = path.join(__dirname, req.url === '/' ? 'index.html' : req.url )
    let contentType = getContentType(filePath) || 'text/html';
    let emptyPagePath = path.join(__dirname, '', '404.html')
    fs.readFile(filePath, 'utf8', (err, data) => {
        if (err) {
            if (err.code === 'ENOENT') {
                res.writeHead(404)
                res.write('Error: File not found') 
                res.end()
            } else {
                res.writeHead(500)
                res.write('A server error has occured')
                res.end()
            }
        }
        
        if (!err) {
            res.writeHead(200, {'Content-Type': contentType})
            res.write(data)
            res.end()
        }
    })
});

const getContentType = (filePath) => {
    const extName = path.extname(filePath);
    
    if (extName === '.js') return 'text/javascript';
    if (extName === '.css') return 'text/css';
    if (extName === '.jpg') return 'img/jpg';
    // if (extName === '.js') return 'text.javascript';
}

server.listen(port, (error) => {
    if (error) console.log("Something went wrong", error)
    else console.log('Server is listening on port', port)
});