nodejs express server code example

Example 1: express.js server

/* ====== create node.js server with express.js framework ====== */
// dependencies
const express = require("express");

const app = express();

app.get("/", (req, res) => {
   res.send("This is home page.");
});

app.post("/", (req, res) => {
   res.send("This is home page with post request.");
});

// PORT
const PORT = 3000;

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


// ======== Instructions ========
// save this as index.js
// you have to download and install node.js on your machine
// open terminal or command prompt
// type node index.js
// find your server at http://localhost:3000

Example 2: express hello world

//to run : node filename.js
const express = require('express')
const app = express()
const port = 3000

app.get('/', (req, res) => res.send('Hello World!'))

app.listen(port, () => console.log(`Example app listening at http://localhost:${port}`))

//visit localhost:3000
// assuming you have done 1) npm init 2) npm install express

Example 3: how to create server in node js using express

You can run the application generator with the npx command (available in Node.js 8.2.0).
$ npx express-generator
For earlier Node versions, install the application generator as a global npm package and then launch it:
$ npm install -g express-generator
For example, the following creates an Express app named myapp. The app will be created in a folder named myapp in the current working directory and the view engine will be set to Pug:
$ express --view=pug myapp

   create : myapp
   create : myapp/package.json
   create : myapp/app.js
   create : myapp/public
   create : myapp/public/javascripts
   create : myapp/public/images
   create : myapp/routes
   create : myapp/routes/index.js
   create : myapp/routes/users.js
   create : myapp/public/stylesheets
   create : myapp/public/stylesheets/style.css
   create : myapp/views
   create : myapp/views/index.pug
   create : myapp/views/layout.pug
   create : myapp/views/error.pug
   create : myapp/bin
   create : myapp/bin/www
Then install dependencies:
$ cd myapp
$ npm install
On MacOS or Linux, run the app with this command:
$ DEBUG=myapp:* npm start
On Windows Command Prompt, use this command:
> set DEBUG=myapp:* & npm start
On Windows PowerShell, use this command:
PS> $env:DEBUG='myapp:*'; npm start
Then load http://localhost:3000/ in your browser to access the app.
The generated app has the following directory structure:
.
├── app.js
├── bin
│   └── www
├── package.json
├── public
│   ├── images
│   ├── javascripts
│   └── stylesheets
│       └── style.css
├── routes
│   ├── index.js
│   └── users.js
└── views
    ├── error.pug
    ├── index.pug
    └── layout.pug

7 directories, 9 files
The app structure created by the generator is just one of many ways to structure Express apps. Feel free to use this structure or modify it to best suit your needs.

Example 4: how to make an express server

// this is your code
// ZDev1#4511 on discord if you want more help!
// first you should install express in the terminal
// `npm i express`.
const express = require('express');
const app = express();

// route
app.get('/', (req,res)=>{
  // Sending This is the home page! in the page
  res.send('This is the home page!');
});

// Listening to the port
let PORT = 3000;
app.listen(PORT)

// FINISH!

Example 5: express js server

const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

app.get('/', (req, res) => {
  res.send('<h1>Some HTML</h1>');
  res.send('<p>Even more HTML</p>');
});

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

Example 6: node js express

basic server

const express =require('express');
const app = express();
const PORT = 5000;


app.get('/',(req,res)=>{
   res.json({message: 'Welcome to the backend'})
})


app.listen(PORT ,()=>console.log(`Connected to ${PORT}`)