Get Your Node.js Under Control with TypeScript

Yaniv RodenskiSenior Architect

Level: Intermediate - Advanced

About me:

• Senior Architect – Sela Group• Windows Azure MVP• Coauthor of Developing Windows Azure

and Web Services (MOC 20487)• Developing software professionally since

1997

About 1997:

About 1997:

Script-based server side

Shared hosting environment

Browser wars

New HTML standard that will “Change the World”

This guy was the PM of Israel

Agenda:

• Introduction to Node.js• Introduction to TypeScript• Getting Node.js under control

Back to the future – Node.js

• A JavaScript runtime that is designed for asynchronous IO operations

• Very lightweight and fast• Used by a growing number of companies:

The Node.js ecosystem• Web frameworks

– Express.js– Socket.io

• Database support– MongoDB– SQL Server

• Hosting and Cloud environments– IIS, Azure– Forever, PM2

Demo

Hello Node.js

Wait! JavaScript on the server side?

• JavaScript is considered a second-class language:• "JavaScript is Assembly Language for the Web“ - Erik

Meijer• “You can write large programs in JavaScript. You just

can’t maintain them.” - Anders Hejlsberg

Hmmm

JavaScript benefits

• But JavaScript is a powerful language:• Functional• Object Oriented• Dynamic

• Great runtimes• Huge community • Tools

Demo

Fun with dynamic typing

So what is TypeScript?

• TypeScript is one of many new JavaScript front ends:– DART– CoffeeScript– ClojureScript

• A JavaScript superset• Introduces static typing for JavaScript• Some ECMAScript 6 features

Key Features:

Support standard

JavaScript code

Provides static typing

Encapsulation through

classes and modules

Support for constructors,

properties and

functions

Interfaces and enums

support

Lambda support =>

Intellisense and syntax checking

Demo

Getting TypeScript

Demo

Fun with static typing

How good is the TypeScript output?

Demo

TypeScript and Node.js

Synchronous server operations

Client

DBServer

Client

Asynchronous server operations

Client

DBServer

Client

Express

• ExpressJS is a web application framework inspired by Sinatra

• Minimal and flexible• Provide a quasi-MVC server side

development

Demo

Doing cool things with Express

Summary

• Node.js is a powerful and lightweight out-of-browser JavaScript environment

• JavaScript is a powerful language by itself• TypeScript provides optional static typing

and cleaner syntax and tools, which can be handy while developing large applications and exposing APIs

Resources

• Node.js: http://nodejs.org/• TypeScript: http://www.typescriptlang.org/• Slides and Demos: http://sdrv.ms/152qU0b• Definitely Typed:

https://github.com/borisyankov/DefinitelyTyped

• Twitter: @YRodenski