Basics

Question 1

Create Server

Answer 1

var http = require(‘http’)

http.createServer(function(req,resp){
resp.writehead(200,{content-type:’text/html’}
resp.write(‘blah’)
resp.end
}).listen(8080)

Question 2

how to read url

Answer 2

var url = require(url)
http.createServer(function(req,resp){
resp.writehead(200,{content-type:'text/html'}
resp.write('blah')
var urlValue = url.parse(req.url)
resp.end
}).listen(8080)

Question 3

How to read files

Answer 3

var fs = require(fs)
use fs object to read, edit and delete files

Question 4

How to raise events

Answer 4

var events = require('events')
var eventEmitter = new events.EventEmitter()
//subscribe
eventEmitter.on('som_event',( data)  => { } )
eventEmitter.emit('some random event')

Question 5

What is Node

Answer 5

Node is a runtime built using the open source Program called V8 Engine, to run Javascript outside the browser.
V8 itself is written in C++ and it is the same program which powers the Chrome Browser. Node Compile Javascript to low level Machine level instructions and runs it.

Question 6

Some Commans=ds to run in the node command prompt

Answer 6

Global

process

Question 7

How to export a property from a file in Node

Answer 7

module.export.age = 25

Exports a property named age, with a value 25 from the file

Question 8

Export a new function named Add

Answer 8

module.exports.add = (one,two) => return one + two

Question 9

What is nodemon?

Answer 9

something which listens to file changes and restarts Node automatically.Used only in Dev mode.

Question 10

how to get all command line arguments passed to program

Answer 10

process.argv

Question 11

Which plugin can be used to process command line arguments

Answer 11

yargs

Question 12

Which framework is used to serve static files from node

Answer 12

express-static

Question 13

Commonly used Express MiddleWares

Answer 13

body-parser : This is used to parse the body of requests which have payloads attached to them

cookie-parser: parses Cookie header and populate req.cookies with an object keyed by cookie names

express-session: creates a session middleware with the given options.

Question 14

How to create an express server

Answer 14

var express = require("express")
var app = express()
app.get("/",(req,res) => {})
app.listen(8000)

Question 15

How to add middlewares in express

Answer 15

var express = require("express")
var app = express()
app.use(MIDDLEWARES)
app.get("/",(req,res) => {})
app.listen(8000)

Question 16

how to create router middleware

Answer 16

var express = require("express")
var app = express()
var router = express.Router()
router.get('/hello',(req,res) => { })

Question 17

how to serve static files from Express?

Answer 17

var express = require('express');
var app = express();

//To Serve static files from folders names Public and Images.

app. use(express.static(‘public’));
app. use(express.static(‘images’));

Question 18

Which middleware is used in Express to process form data

Answer 18

var bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: true })

Question 19

Which middleware is used in Express to process Multi- part form data

Answer 19

var multer = require('multer');
var upload = multer();
app.use(upload.array());

Question 20

How to set cookie on a request

Answer 20

var cookieParser = require(cookie-Parser”)

app. use(cookieParser())
router. get(“/sendCookie”, (req,res) => {
res. cookie(“name”,”Panji Mittai”).send(“cookie set”)

})

Question 21

Framework to do microservices in Nodejs

Answer 21

Moleculer