Ruby Course - Lesson 7 - Mashups With Ruby

Mashups with Ruby

Monday, September 13, 2010

Today’s lesson

Introduction to mashups

Basic introduction to common technologies - REST, JSON

Mashups

Using Google ClientLogin for authentication

Using HostIP to geocode your IP and Geonames to find nearby street names


What’s a mashup?


A method of programming that uses data and/or

service from one or more sources external from the

system


Basically, getting someone else to do the

‘dirty’ job


Web as a platform


Types of mashups


Types of mashups

DataService


Types of mashups

DataService

API

SDKRedirect


Types of mashups

DataService

API

SDKRedirect

Mashup app

Mashup plug-in


Some examples





Common mashup methods



SDKs• Language specific packages• Use language specific APIs• Tight integration with application



Web APIsSDKs• Language specific packages• Use language specific APIs• Tight integration with application




XML-RPC• Remote procedure call

(RPC)• Use XML to package RPC• Transport over HTTP






SOAP• Use XML to package

data and calls• Transport over HTTP

and others• More used in

enterprise settings






SOAP• Use XML to package

data and calls• Transport over HTTP

and others• More used in

enterprise settings

REST• Describe the transfer

and action on resources that are identified by URI

• closely tied to HTTP• Most popular in Web

2.0 apps


RESTful web services


Uses HTTP methods explicitly


GET /adduser?name=Robert HTTP/1.1

Creating a new user (non-REST)


GET /adduser?name=Robert HTTP/1.1

Creating a new user (non-REST)

Creating a new user (REST)POST /users HTTP/1.1Host: myserverContent-Type: application/xml<?xml version="1.0"?><user> <name>Robert</name></user>


Deal with resources identified by URIs


Stateless


Transfer XML, JSON, YAML etc


JSONJavascript Object Notation


Lightweight text-based exchange standard designed for human-readability

Often used as an alternative to XML{ "firstName": "John", "lastName": "Smith", "age": 25, "address": { "streetAddress": "21 2nd Street", "city": "New York", "state": "NY", "postalCode": "10021" }, "phoneNumber": [ { "type": "home", "number": "212 555-1234" }, { "type": "fax", "number": "646 555-4567" } ] }


Accessing REST APIs with Ruby


RestClienthttp://github.com/archiloque/rest-client


http://github.com/archiloque/rest-client

http://github.com/archiloque/rest-client

RestClient.get 'http://example.com/resource'

RestClient.get 'http://example.com/resource', {:params => {:id => 50, 'foo' => 'bar'}}

RestClient.get 'https://user:[email protected]/private/resource', {:accept => :json}

RestClient.post 'http://example.com/resource', :param1 => 'one', :nested => { :param2 => 'two' }

RestClient.post "http://example.com/resource", { 'x' => 1 }.to_json, :content_type => :json, :accept => :json

RestClient.delete 'http://example.com/resource'

response = RestClient.get 'http://example.com/resource'response.code➔ 200response.cookies➔ {"Foo"=>"BAR", "QUUX"=>"QUUUUX"}response.headers➔ {:content_type=>"text/html; charset=utf-8", :cache_control=>"private" ...


Most of the time, you will be using some gem to access the web APIs


Hands-on #1Authenticating with Google ClientLogin

http://code.google.com/apis/accounts/docs/AuthForInstalledApps.html




Preferred external authentication is through

OAuth or Open ID

NOTE!





%w(rubygems haml sinatra rack-flash json rest_client).each { |gem| require gem}%w(models helpers).each {|feature| require feature}

set :sessions, trueset :show_exceptions, falseuse Rack::Flash

get '/' do redirect '/dashboard' if session[:id] redirect '/login'end

get '/login' do haml :login, :layout => false end

post '/login' do if authenticate(params[:email], params[:password]) redirect '/' else redirect_with_message '/login', 'Email or password wrong. Please try again' endend

get '/logout' do session.clear redirect '/'end

get '/dashboard' do require_login haml :dashboardend

error do redirect '/' end

auth.rb


helpers do def require_login redirect_with_message('/login', 'Please login first') unless session[:id] end def authenticate(email, password) response = RestClient.post('https://www.google.com/accounts/ClientLogin', 'accountType' => 'HOSTED_OR_GOOGLE', 'Email' => email, 'Passwd' => password, :service => 'xapi', :source => 'Goog-Auth-1.0') do |response, request, result, &block| user = User.find :email => email if response.code == 200 and not user.nil? session[:id] = response.to_s session[:user] = user.id.to_s return true end return false end end

def redirect_with_message(to_location, message) flash[:message] = message redirect to_location endend

helpers.rb


https://www.google.com/accounts/ClientLogin'

https://www.google.com/accounts/ClientLogin'

class User attr :email def self.find(options) return true if options[:email] = '[email protected]' endend

models.rb

Change this in your own code when trying out this

hands-on (should be GMail account)


mailto:[email protected]

mailto:[email protected]

Hands-on #2Geocode your IP with HostIP and find nearest

street with Geonames http://www.hostip.info/

http://www.geonames.org/export/ws-overview.html


http://www.hostip.info

http://www.hostip.info




get '/geo' do require_login location = location_from_ip @loc = location['Country'] @ip = location['IP'] @long = location['Longitude'] @lat = location['Latitude'] nearby_streets = find_nearby_with @lat, @long @street_names = nearby_streets['streetSegment'].collect { |segment| segment['name'] }.uniq haml :geoend

auth.rb


def location_from_ip response = RestClient.get "http://api.hostip.info/get_html.php?position=true" YAML.load response.bodyend

def find_nearby_with(lat,long) response = RestClient.get "http://ws.geonames.org/findNearbyStreetsOSMJSON?lat=#{lat}&lng=#{long}" JSON.parse response.bodyend

helpers.rb

Should normally use ip=#{request.ip} to get the user’s incoming IP


http://api.hostip.info/get_html.php?position=true




http://livepage.apple.com/




Questions?


Documents

Ruby Course - Lesson 7 - Mashups With Ruby