require express server js

1/* ====== create node.js server with express.js framework ====== */
2// dependencies
3const express = require("express");
4
5const app = express();
6
7app.get("/", (req, res) => {
8   res.send("This is home page.");
9});
10
11app.post("/", (req, res) => {
12   res.send("This is home page with post request.");
13});
14
15// PORT
16const PORT = 3000;
17
18app.listen(PORT, () => {
19   console.log(`Server is running on PORT: ${PORT}`);
20});
21
22
23// ======== Instructions ========
24// save this as index.js
25// you have to download and install node.js on your machine
26// open terminal or command prompt
27// type node index.js
28// find your server at http://localhost:3000

1// npm init
2// npm i express
3
4const express = require('express');
5const server = express();
6
7const PORT = 3000;
8
9// Body parser
10server.use(express.json());
11
12// Homme page
13server.get('/', (req, res) => {
14  return res.send("<h1 style='text-align: center;'>Hello,<br />from the Express.js server!</h1>");
15})
16
17// About page
18server.get('/about', (req, res) => {
19  return res.send('<h2 style="text-align:center">About us</h2>');
20})
21
22// 404 page
23server.use((req, res, next) =>{
24  res.status(404);
25
26  // respond with html page
27  if (req.accepts('html')) {
28    res.sendFile(__dirname + '/error404.html');
29    return;
30  }
31  // respond with json
32  else if (req.accepts('json')){
33    res.send({
34      status: 404,
35      error: 'Not found'
36    });
37    return;
38  }
39  // respond with text
40  else {
41    res.type('txt').send('Error 404 - Not found');
42  }
43});
44
45// Listening to the port
46server.listen(PORT, () => {
47  console.log(`Server is running on port ${PORT}`);
48});
49
50// Running the server: node server.js

1const express = require('express')const app = express() app.get('/', function (req, res) {  res.send('Hello World')}) app.listen(3000)