Intro to Node.js

Intro to Node.js

• 1.
  Introducing Node.js
• 2.
  About Your Speaker
• 3.
  What Is It?  Serverside javascript framework  Written using Google V8 Engine  Uses CommonJS module system  Has the latest and greatest Ecmascript5 features
• 4.
  Non-Blocking I/O  The philosophybehind node.js is that system interactions should be non-blocking  Instead of this: var data = fs.readFile('foo.txt') console.log(data);  This: fs.readFile('foo.txt', function(data){ console.log(data); });
• 5.
   This whole operationis asynchronous... my application doesn't have to wait for the file to be read in  Using javascript to do this makes it easier to adopt given the existing knowledge of using callbacks and listeners on the client side
• 6.
  Event Driven Architecture  Thisleads to a more event driven approach  Rather than returning something, calls should try to either − Call a callback passed in − Fire events that the caller listens for  Built in event system (EventEmitter) − emitter.emit('data-recvd', evt) − emitter.on('data-recvd', function(evt){ });
• 7.
  Ecmascript 5 Features
• 8.
  Ecmascript 5 Features  ArrayExtras − Map, reduce, forEach, filter, every, some  JSON  Object Utilities  Object.getOwnPropertyNames  Object.create  Object.defineProperties  Object.getOwnPropertyDescriptor  Immutibility − Object.freeze, Object.seal
• 9.
  Ecmascript 5 Features  Getters/setters  Function.prototype.bind −Allows you to create a new function with the argument(s) pre-set − Example function add(a,b){ return a+b; } var fivePlus = add.bind(5) console.log(fivePlus(2)); // prints 7
• 10.
  Examples  Enough talking, let'ssee some examples − Some file and process interaction − A simple webserver − Reverse proxy − Websockets − AMQP to integrate with existing applications
• 11.
  Getting Started  Runs onnix and cygwin (no windows support yet)  Install the latest stable from nodejs.org − Sorry, no installer. You'll need to build it yourself  Try the commandline repl out. If all is well, you're good to go!  Hack away
• 12.
  npm  Ruby has gem,node has npm (node package manager)  This is a must have for node.js development − http://npmjs.org  Quick Install: − curl http://npmjs.org/install.sh | sh  Can also be used to budle up your application's dependencies
• 13.
  Modules of Note  Someinteresting modules to take note of and try out − Express – simple sintatra clone (a dime a dozen these days) − Vows – async BDD in javascript − Socket.IO – websockets made easy − Yui3 – adaption of YUI for node.js − SEVERAL NoSQL modules  Riak, redis, couchDB, mongoDB, tokyo cabinet, etc.
• 14.
  Hosting Options  Heroku (closedbeta)  Joyent (open beta)  Nodjitsu (launching soon)  DIY (EC2, your own server, etc)
• 15.
  Cons  Evolving rapidly. − It'snot uncommon to see tutorials from several months ago that no longer work  Not very cross platform (yet)  Lots of duplicate modules − Not that this is a bad thing, but for example there are TEN couchdb modules (because couchdb wrappers are simple to make)  No clustering support yet
• 16.
  Clustering Support  No realsupport yet, but it's on the way! − EventEmitters backed by websockets − Another using Redis built-in publish/subscribe mechanisms − I've been hacking at EventEmitters backed by AMQP
• 17.
  Users
• 18.
  Join the Community!  irc.freenode.net#node.js  Google Groups node.js  File bugs/suggest features  Use and Contribute!