start a server with node code example

Example 1: create server with node js

const express = require('express');
const server = express();

const PORT = 3000;

// Homme page
server.get('/', (req, res) => {
  return res.send("<h1 style='text-align: center;'>Hello,<br />from the Express.js server!</h1>");
})

// About page
server.get('/about', (req, res) => {
  return res.send('<h2 style="text-align:center">About us</h2>');
})

// 404 page
server.use((req, res, next) =>{
  res.status(404);

  // respond with html page
  if (req.accepts('html')) {
    res.sendFile(__dirname + '/error404.html');
    return;
  }
  // respond with json
  else if (req.accepts('json')){
    res.send({
      status: 404,
      error: 'Not found'
    });
    return;
  }
  // respond with text
  else {
    res.type('txt').send('Error 404 - Not found');
  }
});

server.listen(PORT, () => {
  console.log(`Server is running on port ${PORT}`);
});

Example 2: srart server js

require('dotenv').config();

const express = require('express');
const server = express();
const cors = require('cors');
const ejs = require('ejs');
const methodOverride = require('method-override');
const pg = require('pg');
const agent = require('superagent');

const client = new pg.Client(process.env.DATABASE_URL);

server.use(methodOverride('_method'));
server.use(express.static('./public'));
server.use(cors());
server.use(express.urlencoded({extended :true}));
server.set('view engine','ejs');

Example 3: run node app locally

// Run this command in your terminal to start your node application.
// Replace the tag with your applications main file name (ex index.js, main.js etc). 
// Add alternative a relative or absolute path before the name.

node <filename>.js

Example 4: node js creating server

const http = require('http');

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

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

Example 5: create express server local

// create directory

//npm init -y
//npm i express --save

//create public directory
//create server.js

// <---- In the server js file --->

'use strict';

const express = require('express');
const app = express();
app.use(express.static('public'));// to connect with frontend html
app.use(express.json());//body parse

app.get('/', function(req,res){
	res.send('This is the Homepage');
  	//res.sendFile('index.html');
});

app.listen(3000);