introduction to node.js

Introduction to Node.js Please rate this talk: http://spkr8.com/t/19141

Monday, January 14, 13

http://spkr8.com/t/19141

http://spkr8.com/t/19141

Our Goals• What Node Isn't and Is

• How to Install

• Hello World - Node Style

• Node Workflow

• Three Key Ideas

• Introducing NPM

• A Website

• A RESTful Web Service

• Why Node

• Resources

• Summary


Disclaimer

The opinions expressed in this talk are my own and don’t represent those of my employer, my friends, my family, or even me.


Who am I?I am a Microsoft Certified Solution Developer and I’ve been developing software since 1979. Since 2009, I have been focused on developing mobile applications, for iPhone, Android, the mobile web, and Windows Phone 7.


Who Are You? (I hope)

• Experienced with JavaScript

• Experience with some other server framework

• Familiar with the Unix Tool Chain

• Familiar with Git


What Node Isn't and Is?

• What Node Isn't?

• What Node Is?

• How to Spell It?


What Node Isn't?


What Node Is?

• The Official Answer

• It is built on Google's V8

• The Server and the App Are One


The Official Answer

• Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.


http://code.google.com/p/v8/




It is built on Google's V8

• Google’s Open Source JavaScript Engine

• V8 is really fast

• It is compiled, sort of


The Server and The App Are One

• Unlike Other Technologies

• IIS and ASP.NET ( aspnet_wp.exe)

• Apache HTTP and PHP

• Complete Control of the HTTP Request


How to Spell It?

• Node.js

• Node.JS

• Node (my preferred spelling)


How to Install

• http://nodejs.org/downloads

• Mac/PC/Linux/SunOS

• Azure

• http://www.windowsazure.com/en-us/develop/nodejs/


http://www.windowsazure.com/en-us/develop/nodejs/




Hello World Node Style

var http=require('http');

http.createServer(function (req, res) {

res.writeHead(200, { 'Content-Type': 'text/plain});

res.end('Hello World\n');

}).listen(3000);

console.log('Server running at http://localhost:3000/');


http://localhost:3000/


A Slightly Better Hello World

var http=require('http');

var server = http.createServer();

server.on(function (req, res) {

res.writeHead(200, { 'Content-Type': 'text/plain});

res.end('Hello World\n');

}).listen(3000);

console.log('Server running at http://localhost:3000/');




Node Workflow

• The REPL

• Developing

• Publishing


The REPL

• Read - Eval - Print Loop

• Brings JavaScript to the command line

• Allows all JavaScript commands

• Isn’t Really too useful


Developing

• Text Editor / Terminal

• VIM

• WebStorm


Publishing with Git

• Git

• Microsoft Azure

• Heroku


Three Key Ideas

• Callbacks

• Events

• Modules


Callbacks

• Callbacks are the key to Asynchronous Programming

• Avoid thinking in Java or C# with callbacks

query(“SELECT * from db”, function(result) {

/* do something with result */

});


Events

• Events are Core to Node’s Architecture

• Events are defined in the Module, Events

• Events are hooked using .on

• Events are triggered using .emit

• Your code can define and emit events also


Modules

• Based on CommonJS

• Solves the Issue of the JavaScript Global Object

• Modules are wrapped in anonymous functions


Modules(function() {

/* contents of module file */

})();


Introducing NPM

• Node Package Manager

• http://npmjs.org

• Core

• Userland

• Types of Installs

• Don’t Re-invent the Wheel


Core

• Packages that are internal to Node

• Defined in Node's source in the lib/ folder

• Modules like: http, util, fs, etc.


Userland

• Modules loaded from NPM or other

• npm install <module name>

• npm install -g <module name>


Types of Installs

• Global - Accessible to all Node Apps

• Local - Accessible only to the current App

• Prefer Local

• App has all components when published

• No need to sudo


Don’t Re-invent the Wheel

• There are over 20k Packages already defined

• Most of your problems have already been solved


Top Ten Packages

• #10 connectConnect is an extensible HTTP server framework for node, providing high performance "plugins" known as middleware. Connect is bundled with over 20 commonly used middleware, including a logger, session support, cookie parser, and more.


Top Ten Packages

• #9 coffee-scriptCoffeeScript is a little language that compiles into JavaScript.


Top Ten Packages

• #8 underscoreUnderscore.js is a utility-belt library for JavaScript that provides support for the usual functional suspects (each, map, reduce, filter...) without extending any core JavaScript objects.


Top Ten Packages

• #7 jadeJade is a high performance template engine heavily influenced by Haml and implemented with JavaScript for node.


Top Ten Packages

• #6 redisThis is a complete Redis client for node.js. It supports all Redis commands, including many recently added commands like EVAL from experimental Redis server branches.


Top Ten Packages

• #5 mochaMocha is a simple, flexible, fun JavaScript test framework for node.js and the browser.


Top Ten Packages

• #4 socket.ioSocket.IO is a Node.JS project that makes WebSockets and realtime possible in all browsers. It also enhances WebSockets by providing built-in multiplexing, horizontal scalability, automatic JSON encoding/decoding, and more.


Top Ten Packages

• #3 asyncAsync is a utility module which provides straight-forward, powerful functions for working with asynchronous JavaScript. Although originally designed for use with node.js, it can also be used directly in the browser.


Top Ten Packages

• #2 requestSimplified HTTP request client.


Top Ten Packages

• #1 ExpressFast, unopinionated, minimalist web framework for node.


A Website


A RESTful Web Service


Why Node?

• Avoids the Web Dev Context Switch

• Gives You Full Control of the Server

• Makes Asynchronous Coding Easy

• Node is Fun


Resources

• http://nodejs.org

• http://npmjs.org

• http://nodetuts.com

• http://howtonode.org

• http://package.json.nodejitsu.com


http://nodejs.org

http://nodejs.org

http://npmjs.org

http://npmjs.org

http://nodetuts.com/

http://nodetuts.com/

http://howtonode.org/connect-it

http://howtonode.org/connect-it

http://package.json.nodejitsu.com/

http://package.json.nodejitsu.com/

Summary• What Node Isn't and Is

• How to Install

• Hello World - Node Style

• Node Workflow

• Three Key Ideas

• Introducing NPM

• A Website Using Packages

• A RESTful Web Service

• Why Node

• Resources

• Summary


introduction to node.js

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