Web Services And SOAsubin.s.sugunan@gmail.com

What’s Inside

SOA What are Web Services History Types WSDL, UDDI and SOAP RESTful Web Service WADL Debugging and Testing Security

Intent

Most enterprises have made extensive investments in system resources over the course of many years. Such enterprises have an enormous amount of data stored in legacy enterprise information systems (EIS),so it's not practical to discard existing systems. It's more cost-effective to evolve and enhance EIS. But how can this be done ?

SOA and WebServices is the key

SOA SOA is a Software Design Approach Conceptually a collection of services on a network that communicate with one

another. Services are loosely coupled SOA is a higher level of application development. SOA typically leverages on standards based integration. The key players include service provider and service consumer

Web Services Vision

What Are Web Services ?

Software Components that can be published, located and run over the internet

The Concept of SOA is realized using web services

[W3C (working group) definition]

"A Web service is a software application identified by a URI, whose interfaces and bindings are capable of being defined, described and discovered as XML artifacts. A

Web service supports direct interactions with other software agents using XML based messages exchanged via internet-based protocols."

History of Web servicesWeb Services have evolved through three distinct Phases.

Phase Period Description

1 1999-01 Set timeline for the adoption of Web Services. Many Web Services development tools delivered from Microsoft, IBM, Sun, Software AG, Oracle and many others.

2 2002-04 Business Web Services start to appear in large numbers. Adoption of UDDI Registries in 2003. 40% of financial services transactions leveraged in Web Services models.

3 2005-> A number of issues of previous phases are addressed. These include: Quality of Service (QoS); network reliability; transaction recovery; real-time messaging; security; and billing mechanisms. Adapted dynamic Web Services. Organizations changed not only their business processes, but also their business models as they move to real-time collaboration and integration of processes both within and between enterprises..

Type of Web services

SOAP REST

and more… ..

SOAP - a type of Web Service [JAX-WS]

Let’s see an example

The key players: WSDL, UDDI and SOAP

Describing a web service: WSDL

<types>

The types element defines the data types exchanged when the web service is invoked.The parameters passed to and returned from a method are considered data types.

<message>

The messages used by the web service. A message may contain more than a message part. Each message part is actually part of the SOAP message being sent, and is either a parameter or result being passed.

<portType>

A portType is the most important part of a WSDL. it defines operations that can be performed and the messages involved.

<binding>

The communication protocols used by the web service

The Web Services Description Language (WSDL) describes all details about how the web service works, where it can be found, and what the client should expect in return etc..

Discovering a service: UDDIUDDI is a platform-independent framework for describing services, discovering

businesses, and integrating business services by using the Internet.

http://www.xmethods.com/ve2/index.po

Defining a message: SOAP

<?xml version="1.0"?><soap:Envelopexmlns:soap="http://www.w3.org/2001/12/soap-envelope"soap:encodingStyle="http://www.w3.org/2001/12/soap-encoding">

<soap:Header>...</soap:Header>

<soap:Body>... <soap:Fault> ... </soap:Fault></soap:Body>

</soap:Envelope>

SOAP is an XML-based protocol to let applications exchange information over HTTP.

Debugging and Testing SOAP Web Services JUnit Eclipse Web Service Explorer SoapUI Web Service Call Composer WebInject JMeter SOAPSonar Personal Edition SOA Cleaner Vordel SOAPbox Storm

SOAP Security SOAP header extensions

XML Signature XML Encryption

More WS-Security

WS-Policy WS-Trust WS-Privacy WS-SecureConversation Ws-Federation Ws-Authorization

And probably a few more…

REST - another Web Service [JAX-RS] REST (representational state transfer) is an approach for getting information content

from a Web site by reading a designated URI that contains an XML file that describes and includes the desired content.

Use HTTP methods for CRUD create – POST read – GET update – PUT delete – DELETE

Let’s see an example

WADL - REST equivalent of a WSDLWADL – Web Application Description Language

Debugging and Testing RESTful Web Services

JUnit SoapUI SOA Cleaner Rest-client

FireFox Add-Ons

Firebug Poster RESTClient RESTTest HTTP Resource Test

REST SecurityREST offers no built-in security features, encryption, session management, QoS

guarantees, etc. But also as with Web Services, these can be added by building on top of HTTP

• For security, username/password tokens are often used.• For encryption, REST can be used on top of HTTPS (secure sockets).

SOAP vs REST Data formats Caching Bandwidth Usage Security Tools

Resources http://www.w3schools.com/webservices/default.asp http://www.databaseanswers.org/web_services_history.htm http://www.w3schools.com/soap/default.asp http://www.w3schools.com/wsdl/default.asp www.genomeutwin.org/events/SENGER_060504_webservices.ppt www.ict.csiro.au/mu/Trends/Presentations/CSIROWebServices.pdf RESTful Web Services.pdf By Daniel Glauser

Thank You