Web 2.0 Mashups Project Proposal UCLA CS130, Spring 2007

Web 2.0 MashupsProject ProposalUCLA CS130, Spring 2007 Alex Rodriguez SWG – Tivoli arodrigu@us.ibm.com Chris Montalvo GBScdmontal@us.ibm.com Martin Stenkilde SWG – Rationalmstenkil@us.ibm.com Gergana Markova SWG – Tivoligmarkova@us.ibm.com

Mashup • A hybrid application that combines content from more than one source. • Very popular Web 2.0 idea • Mash-up (you can use a hyphen if you want)

Why Mash? • Mashups are the next logical step in Service Oriented Architecture • The real power in Web services comes from combining • Web services are typically specialized, mashups are “situational” • Development without central authority

Web 2.0 • Web 2.0: O’Reilly Media coined the term • Web 1.0 vs. 2.0 • One-to-many vs. many-to-many publishing • Application gets better as publishers make it better vs. application gets better the more people use it • No AJAX vs. AJAX

What is a Web service? • W3C Web Services Architecture Group • “A Web service is a software system designed to support interoperable machine-to-machine interaction over a network. It has an interface described in a machine-processable format (specifically WSDL). Other systems interact with the Web service in a manner prescribed by its description using SOAP messages, typically conveyed using HTTP with an XML serialization in conjunction with other Web-related standards.”

Service Oriented Architecture (SOA) • A style of application design focused on how services are described and organized to support dynamic, automated discovery and use. • Web services implement the service oriented architecture • SOA principles: • Reuse • Modularity • Composability • Interoperability

Service Oriented Architecture Roles Service Registry Publish Advertise service Find Discover service Service Provider Service Requester Bind/Invoke Request service

SOAP • A W3C Specification • An XML format, typically holds information for a Web service method call, or a response • Programming language independent • SOAP expanded: Services-Oriented Access Protocol • Used to be Simple Object Access Protocol

WSDL • Web Services Description Language • A kind of IDL (Interface Definition Language) • An XML format to describe a Web service’s capabilities • Describes a service as a set of endpoints operating on messages

XML/Java • XML Parsers • Parsers help with validation, well-formedness checking, building a DOM, notifying the application of errors • Two API Standards: DOM and SAX • Xerces2 • Data Binding APIs

Axis • Apache Extensible Interaction System • A SOAP Engine • A JAX-RPC run-time system • Provides emitter tooling that generates Java classes from WSDL • Used to be IBM SOAP4J

JAX-RPC • A Sun specification, was JSR 101 • Specifies Java APIs for XML-based Remote Procedure Call • Remote Procedure Call • A mechanism for clients to call procedures from a service over a network • Typically used in distributed client/server model • Other example of RPC mechanism: RMI

A Very Simple Example • The Library Web service • Exposes one method: findTitleByAuthor • Uses Axis “instant deployment” with a JWS file • Generates a Web service client from the Library service WSDL

Service Implementation - Library.jws import java.util.*; publicclass Library { private LibraryDatastore dataStore; public Library() { DatastoreFactory.getDS(); dataStore = DatastoreFactory.getLibraryDataStore(); } public Collection findTitleByAuthor(String author) { ... } }

Axis Instant Deployment $tomcat_home/webapps/axis http://127.0.0.1:8080/axis/Library.jws?wsdl

WSDL2Java Generates

Service Client – LibraryClient.java import java.util.*; import org.library.*; publicclass LibraryClient { publicstaticvoid main(String[] args) { try { LibraryService libraryLocator = new LibraryServiceLocator(); Library library = libraryLocator.getLibrary(); Object[] titles = library.findTitleByAuthor(args[0]); for (Object title : titles) { System.out.println(title); } } catch (Exception e) { e.printStackTrace(); } } }

Suggested Approach • Environment setup • Service discovery • Your Mashup Concept • Design / Storyboard • Component Level Design • Implementation • Test • Deployment (Go Live)

Web service Providers

Real Mashup Examples • http://www.allapis.com/Yahoo_Flickr_Weather_Maps.aspx • Allows users to search US cities/locations - provides users with information on the city requested • Weather Forecasts • Wikipedia geo Articles • Flickr photos • APIs used • Flickr • GeoNames • Yahoo Geocoding • Yahoo Maps

Real Mashup Examples • www.corozalmapia.com • The site is not complete, however the concept is interesting • This specific site is a map of Corozal Town Belize (Central America). • Each attraction on the map is clickable • Once clicked the user can see pictures and video of each attraction • APIs used • Google AdSense • Google Maps • YouTube

Skills Required • Java Programming, nothing fancy • Basic web service concepts: SOAP, WSDL • Basic web-application concepts: URLs, HTTP, JavaScript, server-side scripting (JSP, PHP, other) • Basic XML (syntax, parsing) • AJAX (would be nice) • CSS (optional)

Gain Experience • J2EE • Web services • SOAP • Axis • JAX-RPC • XML • Web UI • AJAX

Links and References (1) • Documentation / Specifications • developerWorks – SOA and Web services • http://www-128.ibm.com/developerworks/webservices/ • SOAP • http://www.w3.org/TR/soap/ • WSDL • http://www.w3.org/TR/wsdl • JAX-RPC • http://java.sun.com/webservices/jaxrpc/ • SOAP Engine • Axis • http://ws.apache.org/axis/ • Eclipse • http://www.eclipse.org/

Links and References (2) • Web service Providers (WSDL) • Google Code • http://code.google.com/ • Yahoo Developer Network • http://developer.yahoo.com/ • Amazon ECS • http://www.amazon.com/exec/obidos/tg/browse/-/12738641 • Flickr Web services • http://www.flickr.com/services/api/ • YouTube API • http://www.youtube.com/dev • Microsoft Web services • http://www.momentumsi.com/MSWSDLHunt.html

Questions • Questions?

Web 2.0 Mashups Project Proposal UCLA CS130, Spring 2007