TypeScript for Backend

Seiji Villafranca

developing Rest APIs using Nest Js

Seiji Villafranca

github.com/SeijiV13

Technical Lead, Frontier Software Asia Philippines

Trainer, RakSquad

Auth0 Ambassador

Community Lead, AngularPH,

seijivillafranca.com

Talks

Typescript and Nest

Let me tell you some JavaScript First

JavaScript?

Programming Language for the Web

Makes Web Pages Interactive

Can Validate Data

Without it, Pages our just Pages!

Well... Javascript is basically for Interacting with the UI

A little about History

Developed in 10 Days

Brendan Eich, September 1995

Mocha

LiveScript

JavaScript

JavaScript Vs. Java

Don't be confused they are not related to each other!

JavaScript is called JavaScript for marketing strategies

Some Facts!

Where is JavaScript Today?

Refrence: https://codeburst.io/javascript-trends-in-2020-b194bebc5ef8

Companies that uses JavaScript

Uses NodeJS on Azure Cloud Platform 

Internet of Things (IoT)

Microsoft

Companies that uses JavaScript

Front End is Pure JavaScript

Developed KrakenJS (own version of express)

Companies that uses JavaScript

Gmail Web Client,  Google Docs

Has own JS Framework AngularJS, Angular

Developed V8 for Chrome which is the heart of Node JS

Seeing JavaScript for the first time

Superset Languages

Prototypes

Dynamic Types

TypeScript

Generics

Interfaces

ES6

Types

A sample code here

class Student {
    fullName: string;
    constructor(public firstName: string, public middleInitial: string, 
        public lastName: string) {
            this.fullName = firstName + " " + middleInitial + " " + lastName;
    }
}

interface Person {
    firstName: string;
    lastName: string;
}

let user = new Student("Jane", "A", "Doe");

Transpiler that provides JS the features of typing,

Object Oriented Programming

Catches Error and provides fixes before running code

Transpiler

Target: ES6/ES5

Browsers don't understand Typescript

Now on 4.2

Community

https://www.typescriptlang.org/community

Famous Frameworks /Libraries

Hybrid Frameworks

Mobile Apps

Desktop Apps

 An open-source, cross-platform, back-end JavaScript runtime environment that runs on the V8 engine

Backend

has the capability to create Rest APIs and GraphQL and connect with databases

What in the world is RESTful APIs???

Node.js Backend

Client calls an endpoint

node gets data from database

Node sends back to client

Node retrieves data

Advantages of Creating Rest APIs in Node

Cost-effective

 

High-performance

Easy to Learn

Building Cross-Platform Applications

Different frameworks are created for node to introduce standards and improve maintainability

Back End Node Framework

Typescript Based

Shares many concepts with Angular that's why its called the perfect match

https://nestjs.com/

Module

Controllers

Providers

use of to organize the application structure.

responsible for handling incoming requests and returning responses

it can inject dependencies; this means objects can create various relationships with each other

Title Text

Flow

Prerequisites

npm install –g @nest/cli

https://nodejs.org/en/

Check npm verision

 Check npm verision

npm -v

nest --version

Good to go?

Install Nest CLI

Install Node JS

Create a new Nest JS Project

nest new <project-name>

Let's Walk the Talk

Typescript fo Backend, developing Rest Apis using Nest Js

By Seiji Ralph Villafranca

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Typescript fo Backend, developing Rest Apis using Nest Js

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