What is Node.JS?
Javascript Engine
Javascript Engine
Javascript Engine
Most Popular Engine
Javascript Engine
Ryan Dahl
NodeJS
You can run JS outside of the browser
Javascript can talk to native machine because of c++
You can create webservers in Javascript Language
What is NodeJS?
NodeJS is a Runtime Env. for Javascript
INSTALLATION
&
SETUP
Architecture
Request
Request
Request
Event Queue
Request
Event Queue
Request
Event Queue
Request
Event Queue
Event Loop
Request
Event Queue
Event Loop
Blocking Operations
Non- Blocking Operations
Request
Event Queue
Event Loop
Blocking Operations
Non- Blocking Operations
Process
Response
Request
Event Queue
Event Loop
Blocking Operations
Blocking Operations
Thread Pool
I need a thread / worker
Assign a worker and
make him work
Return the result
Blocking Operations
Request
Event Queue
Event Loop
Blocking Operations
Request
Event Queue
Event Loop
Response
URL
Uniform Resource Locator
URL
Uniform Resource Locator
https://www.piyushgarg.dev/
URL
Uniform Resource Locator
https://www.piyushgarg.dev/
Protocol:
Hypertext
Transfer
Protocol
Secure
URL
Uniform Resource Locator
https://www.piyushgarg.dev/
Protocol:
Hypertext
Transfer
Protocol
Secure
Domain - User Friendly Name of IP Address of My Server
URL
Uniform Resource Locator
https://www.piyushgarg.dev/
Protocol:
Hypertext
Transfer
Protocol
Secure
Domain - User Friendly Name of IP Address of My Server
Path: / HomePage or Root Path
URL
piyushgarg.dev/about
PATH
URL
piyushgarg.dev/contact-us
PATH
URL
piyushgarg.dev/project/1
Nested PATH
URL
piyushgarg.dev/about?userId=1&a=2
Query Parameters
Working
Request
Working
Request
Response
HTTP METODS
GET
POST
PUT
PATCH
DELETE
HTTP GET
When you want to get some data from the server
HTTP GET
When you want to get some data from the server
HTTP GET
When you want to get some data from the server
https://youtube.com/search
GET Request
HTTP POST
When you want to send and mutate some data in server
HTTP POST
When you want to send and mutate some data in server
POST Request
{ FormData }
HTTP POST
When you want to send and mutate some data in server
POST Request
{ FormData }
HTTP Headers
&
Status Codes
Headers
Headers
Headers
Headers
Headers
Headers
Headers
From: Person A
To: Person B
Weight: 200Gms
Headers
From: Person A
To: Person B
Weight: 200Gms
Data
Extra Info about Packet
Headers
From: Person A
To: Person B
Weight: 200Gms
Data
Extra Info about Packet
Headers
From: Person A
To: Person B
Weight: 200Gms
Data
Headers
Client
Request
Headers
From: 192.168.1.1
To: 10.1.1.2
Content Type: JSON
Data
Headers
Client
Request
Headers
HTTP Headers are an important part of the API request and response as they represent the meta-data associated with the API request and response.
Headers carry information for The request and Response Body.
Headers
Status Codes
404 - Not Found
MongoDB
MongoDB
No-SQL Document Based Database
Strong Support for Aggregation Pipes
Works on BSON format
Best for Node Applications
MongoDB
Collection - "users"
MongoDB
Collection - "users"
Collection - "users"
document-1
MongoDB
Collection - "users"
Collection - "users"
document-1
document-2
MongoDB
Collection - "users"
Collection - "users"
document-1
document-2
document-1
MongoDB
Installation and Setup
MongoDB
> show dbs
> use <db_name>
> show collections
> db.coll.find()
> db.coll.insert()
Model View Controller
Model View Controller
Model
View
Controller
Model View Controller
Model
View
Controller
Authentication
Authentication
Patterns
Authentication
Patterns
Authentication
Patterns
Statefull
Stateless
Which maintains state or data or server side
Which has no state
Statefull
Statefull
Statefull
Statefull
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
Statefull
Parking Ticket
Number: 24
Statefull
Number 24: DLXXXX123
Number 23: DLXXXX134
Number 26: DLXXXX167
Number 27: DLXXXX123
State
Statefull
Statefull
Statefull
username / password
Statefull
username / password
session uid
Statefull
username / password
session uid
uid: 367
Statefull
uid: 367
Statefull
uid: 367
GET /users | uid: 367
Statefull
uid: 367
GET /users | uid: 367
Server checking who is user 367
Statefull
uid: 367
GET /users | uid: 367
response: all users
How to transfer uid?
cookies
response
headers
Express Flow
Auth Middleware
Checks for cookie value or uid, if valid calls next() else rejects the request
endpoint route
Statefull
Number 24: DLXXXX123
Parking Ticket
Number: 24
StateLess
Parking Ticket
Number: 24
StateLess
Parking Ticket
CarNumber 24: DLXXXX123
StateLess
Parking Ticket
CarNumber 24: DLXXXX123
StateLess
Parking Ticket
CarNumber 24: DLXXXX123
StateLess
Parking Ticket
CarNumber 24: DLXXXX123
StateLess
Parking Ticket
CarNumber 24: DLXXXX123