# Express Js
- instal express
- install nodemon
- setup an app

## 1. middleware

-create a basic middleware and show the iportance of the next param

function printUrl(req, res, next){
    console.log(req.OriginalURL);
    next();
}

## 2. express.json

app.use(express.json())

app.post('/form', (req, res) =>{
    const data = req.body
    console.log(data);
    return res.send(`Username: ${data?.username} | Password: ${data?.password}`)
})

## 3. body parser

Used Before Express 4.16+ to parse Json Format

now the express.json handles json parsing

const bodyParser = require('body-parser')
app.use(bodyParser.json())

## 4. express url encoded

app.use(express.urlencoded({ extended: true }));

set the content-type header and body to match urlencoded http request

## 5. morgan
visualise the request status code

npm i morgan

## 6. helmet

used for security layers.

npm i helmet 

## 7. cookies parser

npm i cookie-parser

const express = require('express')
const cookieParser = require('cookie-parser')

const app = express()

app.use(cookieParser())

app.get('/',(req, res) =>{
    res.json(req.cookies);
})

app.get('/setcookie/:name', (req, res)=>{
    if(req.params.name){
        res.cookie(req.params.name, 'hello', {
            maxAge: 10*1000
        })
        res.send(`cookie set to ${req.params.name}`)
    }
})

app.listen(5000)

## 8. cors