1.
Node.js WorkshopTom Hughes-CroucherChief Evangelist / Node Tech Lead@sh1mmertom@joyent.com

2.
Overview• Introduction• Why Server-Side JavaScript?• What is Node?• Using Node• Understanding Node• Node Ecosystem• Programming Style• More Complex applications• Deploying Node apps to the cloud

3.
Introduction• Tom Hughes-Croucher• Chief Evangelist at Joyent• Node.js core contributor• Author of "Up and Running with Node.js"

4.
Scalable Server-Side Code with JavaScriptNode Up and Running Tom Hughes-Croucher

5.
Major update this week

6.
Why Server-Side JavaScript?

7.
JavaScriptprogrammers 3>2>1

8.
Massive Code base of jQuery and other JS libraries

9.
Laziness or “I’m sickof writing stuff twice”I could have said efficiency, but I think we allsecretly long to sit around in our underwear.

10.
ProgressiveEnhancement is free*Remember WWCD (What Would Crockford Do) *close enough

11.
TL;DR:SSJS is Awesome Like a Unicorn riding a Narwhal

12.
If SSJS is so awesomewhy is it "new"?

13.
1. Professionalism

14.
“Yahoo!s corporate motto is: Dont be eval().“

15.
2. JavaScript Runtimes

16.
Runtimes• V8 (Google), C++• Spider Monkey (Mozilla), C++• Rhino (Mozilla), Java

17.
V8 Spider MonkeyJavaScript Performance

18.
8xSep 08! Mar 11!

19.
Anatomy of SSJS

20.
Node { !

21.
Runtime != Browser

22.
No DOM(By default, anyway)

23.
Summary• Benefits of SSJS • Lots of JavaScript expertise • Lots of web code in JS libraries • Write once, run anywhere • Progressive Enhancement• Why SSJS happened now • Professionalism in JavaScript • New generation of JavaScript runtimes

24.
What is Node?

25.
Node• JavaScript programming environment• Uses V8 runtime• Event Driven• Non-blocking libraries• Supports CommonJS module format• Supports C/C++ based add-ons

26.
Woah! Overload.

27.
1. Its JavaScript

28.
See Above.

29.
2. Its Fast

30.
concurrency=300, Smaller is Better 400 300response time (ms) server nginx 200 thin tornado node_buffer 100 24 26 28 210 212 214 216 218 response size (bytes)

31.
3. Its easy to extend

32.
Modules in JSAdd-ons in C

33.
4. Node is _not_ Rails/ Django/etc

34.
Node is bare-bone to the metal

35.
However, the Nodecommunity are making Rails/Django/etc

36.
5. Node is young

37.
Stable is "stable"Unstable moves fast

38.
Using Node

39.
Using Node• Part 1. Installation• Part 2. Basics• Part 3. Getting stuck in

40.
Part 1. Installation

41.
Navea.k.a the easy way

42.
Enki:~ $ wget -q http://github.com/isaacs/nave/raw/master/nave.shEnki:~ $ chmod 755 nave.shEnki:~ $ ./nave.sh install latest

43.
Nave• Installs and versions Node• Allows Node shells with specific versions• Allows you to get latest <-- Stable• May add unstable option in future

44.
Manual Installation

45.
Go to http://nodejs.org/#downloadand get the URL of the current stable release

46.
Enki:~ $ wget -q http://nodejs.org/dist/node-v0.4.10.tar.gzEnki:~ $ tar xzf node-v0.4.10.tar.gzEnki:~ $ cd node-v0.4.10Enki:~/node-v0.4.10 $

47.
Local or system?

48.
Local

49.
Enki:~/node-v0.4.10 $ mkdir ~/localEnki:~/node-v0.4.10 $ ./configure --prefix=~/localChecking for program g++ or c++ : /usr/bin/g++Checking for program cpp : /usr/bin/cpp...Checking for fdatasync(2) with c++ : noconfigure finished successfully (3.466s)

50.
Enki:~/node-v0.4.10 $ makeWaf: Entering directory `/Users/sh1mmer/node-v0.4.10/buildDEST_OS: darwinDEST_CPU: x86Parallel Jobs: 1[ 1/69] cc: deps/libeio/eio.c -> build/default/deps/libeio/eio_1.o/usr/bin/gcc -rdynamic -D_GNU_SOURCE -DHAVE_CONFIG_H=1-DEV_MULTIPLICITY=0 -pthread -g -O3 -DHAVE_OPENSSL=1 -DX_STACKSIZE=65536 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -DHAVE_FDATASYNC=0 -DPLATFORM="darwin" -DNDEBUG -Idefault/deps/libeio -I../deps/libeio -Idefault -I.. ../deps/libeio/eio.c -c -o default/deps/libeio/eio_1.o...

51.
Enki:~/node-v0.4.10 $ make installWaf: Entering directory `/Users/sh1mmer/node-v0.4.10/buildDEST_OS: darwinDEST_CPU: x86Parallel Jobs: 1* installing build/default/config.h as /Users/sh1mmer/local/include/node/config.h* installing build/default/node as /Users/sh1mmer/local/bin/node* installing build/default/src/node_config.h as /Users/sh1mmer/local/include/node/node_config.hWaf: Leaving directory `/Users/sh1mmer/node-v0.4.10/buildinstall finished successfully (0.373s)Enki:~/node-v0.4.7 $

52.
Enki:~/node-v0.4.10 $ echo $PATH/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/local/git/bin:/Users/croucher/Code/narwhal/bin:/opt/local/bin:/usr/local/git/bin:/Users/sh1mmer/binEnki:~/node-v0.4.10 $ node -v-bash: node: command not foundEnki:~/node-v0.4.10 $ echo PATH=~/local/bin:$PATH>> ~/.profileEnki:~/node-v0.4.10 $ node -vv0.4.10

53.
System

54.
Enki:~/node-v0.4.10 $ ./configure...Enki:~/node-v0.4.10 $ make...Enki:~/node-v0.4.10 $ sudo make install...Enki:~/node-v0.4.10 $ node -vv0.4.7Enki:~/node-v0.4.10 $

55.
Exercise• Get Node head from Github using Git• Install to ~/node

56.
Part 2. Basics

57.
node-replInteractive JavaScript terminal

58.
$Enki:~ $ node

59.
$Enki:~ $ node>3>2>1false> true == 1true> true === 1false

60.
> console.log(Hello World);Hello World> .help.clear Break, and also clear the local context..exit Exit the prompt.help Show repl options> .clearClearing context...> .exitEnki:~ $

61.
Enki:~ $ node> var foo = "bar";> foo;bar> .clearClearing context...> fooReferenceError: foo is not defined at [object Context]:1:1 at Interface.<anonymous> (repl:98:19) at Interface.emit (events:27:15) at Interface._ttyWrite (readline:295:12) at Interface.write (readline:132:30) at Stream.<anonymous> (repl:79:9) at Stream.emit (events:27:15) at IOWatcher.callback (net:489:16)

62.
var http = require(http);http.createServer(function (req, res) { res.writeHead(200, {Content-Type: text/plain}); res.end(Hello Worldn);}).listen(8124, "127.0.0.1");console.log(Server running at http://127.0.0.1:8124/);

63.
var http = require(http);//include the http library

64.
http.createServer(function (req, res) {}).listen(8124, "127.0.0.1");//create an http server//when ‘stuff’ happens call this anonymous function//listen on port 8124 of the IP 127.0.0.1

65.
http.createServer(function (req, res) { res.writeHead(200, {Content-Type: text/plain}); res.end(Hello Worldn);})//when ‘stuff’ happens my function fires//I get a request object and a response object//I write to the response object header//HTTP status 200 and content-type ‘text/plain’//close the response with the body://Hello World

66.
console.log(Server running at http://127.0.0.1:8124/);//write Server is running at http://127.0.0.1:8124///to the console

67.
Interactive Debugging

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Enki:~/Code/node-examples $ node --debughelloworld.jsdebugger listening on port 5858Server running at http://127.0.0.1:8124/

69.
Enki:~ $ npm install node-inspectornode-inspector@0.1.8 ./node_modules/node-inspector websocket-server@1.4.04 paperboy@0.0.2Enki:~ $ node-inspectorvisit http://0.0.0.0:8080/debug?port=5858 to startdebugging

70.
Exercises• Modify the HTTP server to return the text "Im learning Node"• Change the HTTP response to HTML and return your text in an HTML page• Return the User-Agent string from the browser as part of your HTML page• Return different textual responses to 2 (or more) browsers

71.
Part 3. Getting Stuck In

72.
HTTP Client

73.
var http = require(http);var request = http.request({host: www.google.com,port: 80, path: /, method:GET});request.on(response, function (response) { console.log(STATUS: + response.statusCode); console.log(HEADERS: +JSON.stringify(response.headers)); response.setEncoding(utf8); response.on(data, function (chunk) { console.log(BODY: + chunk); });

74.
Streaming API

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write(data) write(data) DestinationRequest end() (google.com) response(headers) data(chunk) data(chunk) Response data(chunk) end()

76.
Exercise• Fetch the NYTimes.com and output the contents to the console• Create a web server • Create an HTTP client • POST data to your web server • Output the POST data to console

77.
Events

78.
object.on(event, function() { //stuff} );

79.
EventEmitter

80.
EventEmitter• manage "event handlers" • list of functions to be called per event• provide mechanism to trigger events

81.
var util = require(util), EE = require(events).EventEmitter;util.inherits(MyClass, EE);var myObj = new MyClass();//nb using first class functionsmyObj.on(something, function);

82.
exports.inherits = function (ctor, superCtor) { ctor.super_ = superCtor; ctor.prototype = Object.create(superCtor.prototype, { constructor: { value: ctor, enumerable: false } });};

83.
More than just core

84.
CommonJS Modules

85.
Library format for SSJS

86.
math.jsexports.add = function() { var sum = 0, i = 0, args = arguments, l = args.length; while (i < l) { sum += args[i++]; } return sum;};increment.jsvar add = require(math).add;exports.increment = function(val) { return add(val, 1);};var inc = require(increment).increment;var a = 1;inc(a); // 2

87.
Protipexports.awesome = function() { //yay my code is awesomesauce};var exports.fail = function() { //exports is a global //by redeclaring it as //a local variable //your code _will_ fail};

88.
Exercise• Create a CommonJS module called "fish" • Provide functions to: • swim • mouth breath • flop around• Import your module into a node project• Call the various functions

89.
Node PackageManager (NPM)

90.
NPM is written inJavaScript for Node

91.
Enki:~ $ cat `which npm`#!/usr/bin/env node;(function () { // wrapper in case were in module_context modevar log = require("../lib/utils/log")log.waitForConfig()log.info("ok", "it worked if it ends with")var fs = require("../lib/utils/graceful-fs") , path = require("path") , sys = require("../lib/utils/sys") , npm = require("../npm") , ini = require("../lib/utils/ini") , rm = require("../lib/utils/rm-rf")

92.
Enki:~/Code/node(master) $ npm install expressexpress@2.3.11 ../../node_modules/express mime@1.2.2 connect@1.4.2 qs@0.1.0Enki:~/Code/node(master) $

93.
Yay. Easy.

94.
Install instructions https://github.com/isaacs/npm

95.
Express.js

96.
Sinatra Style MVC framework

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var app = require(express).createServer();app.get(/, function(req, res){ res.send(hello world);});app.listen(3000);

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HTTP Verb Oriented

99.
Middleware

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app.use(express.bodyParser());app.use(express.cookieParser());app.post(/, function(req, res){ // Perhaps we posted several items with a form // (use the bodyParser() middleware for this) var items = req.body.items; console.log(items); res.send(logging);});

101.
Templating

102.
var express = require("express");app.configure(function () { var public = __dirname + "/../public/"; public = require("path").normalize(public); app.set("views", __dirname + "/views"); app.set("view engine", "jade");});app.get("/", function (req, res) { res.render("index", { locals : { h1: Router Stats, scripts : [ "/public/smoothie.js", "/public/raphael.js", "/public/base.js", "/public/gfx.js", "/public/explore.js", "/public/app.js" ] } }});

103.
Exercise• Create an Express server• Serve two different pages based on value of the HTTP Get param "page"• Create a redirect from /old to /new• Set a cookie on the client

104.
Express in depth

105.
Routes• Routes are based on verbs • GET • POST • PUT • DELETE • ALL (not a real verb, but obvious)

106.
Simple routes

107.
app.get(‘/’, function(req,res) { res.send(‘hello root’);});

108.
Routes with variables

109.
app.get(‘/user/:id’, function(req,res) { res.send(‘hello ‘ + req.params.id);});

110.
Optional flags in routes

111.
app.get(‘/:filename?’, function(req,res) { if(req.params.filename) { res.send(req.params.filename); } else { res.send(‘root’); }});

112.
Regex as routes

113.
app.get(///, function(req, res) { //like using ‘/’ ? res.send(‘/’);});

114.
app.get(/^/d+/?$/, function(req,res) { res.send(‘matches a number’);});

115.
app.get(/^/(.+)/?$/, function(req,res) { //note translation of %23, etc res.send(‘Got: ’ + req.params[0]); //also captures become an array});

116.
Using regex todefine parameters

117.
app.get(‘/index.:format((html|json))’,function(req,res) { res.send(Got: + req.params.format);});

118.
app.get(/:id(d+), function(req,res) { //only digits, right? res.send(req.params.id);});

119.
app.get(/:id(d+), function(req,res) { //escape your in strings res.send(req.params.id);});

120.
Routing magic: Router.jsfunction normalizePath(path, keys) { path = path .concat(/?) .replace(//(/g, (?:/) .replace(/(/)?(.)?:(w+)(?:((.*?)))?(?)?/g, function(_, slash, format, key,capture, optional){ keys.push(key); slash = slash || ; return + (optional ? : slash) + (?: + (optional ? slash : ) + (format || ) + (capture || ([^/]+?)) + ) + (optional || ); }) .replace(/([/.])/g, $1) .replace(/*/g, (.+)); return new RegExp(^ + path + $, i);}

121.
Routing magic• If . before :variable? then . is also optional• If ? is not after a variable then only the previous character is affected• / at the end of URLs automatically optional• * Can be used as a wildcard in routes• Includes when end of URL is optional e.g. /app/e?• Regex can be used any place in a route string e.g. /app/(d)r?

122.
Exercises• Create an express app with routes that capture / /products and /services• Create a route that captures the product ID after /product/ e.g. /product/abc12 and returns it in the response• Use a regular expression to restrict the ID parameter to 3 letter followed by 3-5 numbers• Create a route using a regex that matches the entire route

123.
Passing Control• Routes are actually stacked middleware• You can pass control between routes• The next() function calls the next matching route

124.
app.get(/users/:id, function(req, res, next){ var id = req.params.id; if (checkPermission(id)) { // show private page } else { next(); }});app.get(/users/:id, function(req, res){ // show public user page});

125.
Passing Control• next() is a function of router (and defined in the closure containing the route)• router will grab routes in the order they were declared• e.g. since/* will match everything so it should be the last route!• router doesnt care about verbs so you can use all() to operate on all verbs/routes and then use next() to pass to get(), put(), etc

126.
Exercises• Create a simple check for correct product IDs if not pass control to a route showing a custom error page• Use app.all() to check user permission before showing (mock-up) edit controls on a web site

127.
Middleware

128.
Its a pattern

129.
req, resnext()next()next()

130.
req, resnext()next() Dispatchernext() req res

131.
req, res, next

132.
var express = require(express), app = express.createServer();var middleware = function (req, res, next) { req.foo = bar; next();};app.use(middleware);app.get(/, function(req, res) { res.send(req.foo);

133.
var express = require(express), app = express.createServer();var middleware = function (req, res, next) { var send = res.send; res.send = function(d) { res.send = send; res.send(hijacked! + d); } next();};app.use(middleware);app.get(/, function(req, res) { res.send(hi);});

134.
Connect middleware (Renamed express.* for convenience)• logger • profiler• bodyParser • responseTime• cookieParser • basicAuth• session • favicon• static • vhost• errorHandler

135.
var express = require(express), app = express.createServer();app.use(express.logger());app.use(express.bodyParser());app.use(express.cookieParser());app.use(app.router);app.use(express.static(__dirname + /images));app.use(express.errorHandler());app.get(/, function(req, res) { res.send(<html><img src="/image.png"></html);});app.listen(9003);

136.
Ordering matters

137.
Router uses "internalmiddleware"

138.
var express = require(express), app = express.createServer();var middleware = function (req, res, next) { req.foo = bar; next();};app.get(/, middleware, function(req, res) { res.send(req.foo);});

139.
var a, b, c, d;a = b = c = d = function(req,res,next) { next();}var set1 = [a,b];var set2 = [c,d];var all = [set1, set2];app.get(/set1, set1, function(req,res) { res.send(output);});app.get(/set2, [c,d], function(req,res) { res.send(output);});app.get(/all, all, function(req,res) { res.send(output);});

140.
Middleware factories

141.
Middleware are just functions

142.
var a, b, c, d;a = b = c = d = function(req,res,next) { next();}var set1 = [a,b];var set2 = [c,d];var all = [set1, set2];app.get(/set1, set1, function(req,res) { res.send(output);});app.get(/set2, [c,d], function(req,res) { res.send(output);});app.get(/all, all, function(req,res) { res.send(output);});

143.
var mFactory = function(letter) { return function(req,res,next) { var send = res.send; res.send = function(d) { res.send = send; res.send(letter + + d); } next(); }};var set1 = [mFactory(a),mFactory(b)];var set2 = [mFactory(c),mFactory(d)];var all = [set1, set2];app.get(/set1, set1, function(req,res) { res.send(output);});app.get(/set2, set2, function(req,res) { res.send(output);});app.get(/all, all, function(req,res) { res.send(output);});

144.
Exercise• Create a middleware to detect mobile phone browsers and attach a boolean to req• Create an express app that serves up links to an image using staticProvider• Modify Profiler to profile your app and write each profile to a log file• Create a middleware factory that sets the HTTP Expires header based on roles

145.
Error handling

146.
function NotFound(msg){ this.name = NotFound; Error.call(this, msg); Error.captureStackTrace(this, arguments.callee);}NotFound.prototype.__proto__ = Error.prototype;app.get(/404, function(req, res){ throw new NotFound;});app.get(/500, function(req, res){ throw new Error(keyboard cat!);});

147.
app.error(function(err, req, res, next){ if (err instanceof NotFound) { res.render(404.jade); } else { next(err); }});

148.
View Rendering

149.
app.get(/, function(req, res){ res.render(index.ejs, { title: Falsy Demo });});

150.
Enki:~/Code/express-demo $ tree. app.js lib public views index.ejs layout.ejs layout1.ejs partials stylesheet.ejs4 directories, 5 filesEnki:~/Code/express-demo $

151.
Dont forget to installnpm install ejsnpm install jade

152.
layout.ejs<!DOCTYPE html><html lang="en"> <head> <meta charset="utf-8"> <title><%= title %></title> </head> <body> <%- body %> </body></html>

153.
• layout is a framework unless you turn it off• body is a special variable for layout referring to the file specified

154.
app.set(view engine, ejs);app.get(/, function(req,res) { res.render(index, { title:Falsy Demo});});

155.
//globalapp.set(view options), { layout: false;});//or per routeres.render(index, {layout: false});

156.
Partial views

157.
View Partials• Repeating elements• Take a collection• Iterate over the collection• "Built in" variables for managing collections

158.
layout.ejs<!DOCTYPE html><html lang="en"> <head> <meta charset="utf-8"> <%- partial(stylesheet, stylesheets) %> <title><%= title %></title> </head> <body> <h1><%= header %></h1> <%- body %> </body></html>

159.
partials/stylesheet.ejs<link rel="stylesheet" type="text/css" href="<%-stylesheet %>">

160.
res.render(index, { locals: {title: title, header: header, content: content, stylesheets: [/public/style.css] }, });

161.
Exercises• Create an express server that use jade, haml, ejs to render an index page• Create a public folder and include file from it (CSS, images, etc) in your layout• Create a route for /blog/id to accept only digits• Make a fake database (array) of blog posts and use a middleware to validate each id is valid• Create a view for the /blog/id show the correct post• Use a view partial to a preview of each blog post on the index page

162.
Questions