web 2.0 mashups project proposal ucla cs130, spring 2007

© 2002 IBM Corporation

Web 2.0 MashupsProject Proposal

UCLA CS130, Spring 2007

Alex Rodriguez SWG – Tivoli [email protected] Montalvo GBS [email protected] Stenkilde SWG – Rational [email protected] Markova SWG – Tivoli [email protected]

© 2007 IBM Corporation2

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 Requester

Service Registry

Service Provider

FindDiscover service

PublishAdvertise service

Bind/InvokeRequest 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.*; public class Library {

private LibraryDatastore dataStore; public Library() { DatastoreFactory.getDS(); dataStore = DatastoreFactory.getLibraryDataStore(); } public Collection findTitleByAuthor(String author) { ... }}


http://127.0.0.1:8080/axis/Library.jws?wsdl

Axis Instant Deployment

$tomcat_home/webapps/axis


WSDL2Java Generates


Service Client – LibraryClient.java

import java.util.*; import org.library.*;

public class LibraryClient {

public static void 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 Exampleshttp://www.allapis.com/Yahoo_Flickr_

Weather_Maps.aspxAllows 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 Exampleswww.corozalmapia.comThe 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

Documents