how to start npm code example

Example 1: 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 2: how to create npm project

//Load HTTP module
const http = require("http");
const hostname = '127.0.0.1';
const port = 3000;

//Create HTTP server and listen on port 3000 for requests
const server = http.createServer((req, res) => {

  //Set the response HTTP header with HTTP status and Content type
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World\n');
});

//listen for request on port 3000, and as a callback function have the port listened on logged
server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});