Open Source Data Services for
Strategic SOA
utilising
WSO2 Data Services Server
Sumedha Rubasinghe
2009 Air Force Information Technology Conference
Montgomery, Atlanta

Agenda

SOA & Enterprise Data

Need for SOA Data Services

Introduction

Features

Architecture

Use Cases

Getting started & help

Introducing Mattson ...
Hi..
Mattson here..
I am an architect

My manager wants
to see salary increments
done in HRM system to be
reflected in Payroll....
These systems do not
support a programmable
interface..

Oh..Payroll system is using
an Informix database while
HRM writes to a MSSQL
database...

Another scenario

Build a Travel Expense Management System

HRM – MSSQL

Training Mgt – Spreadsheet

Payroll - Informix

Ways of solving

Method 1
– Create a new data store
– Pull relevant data from HRM, Payroll & Training Mgt
Systems
– Store it to match new application’s requirements
– Now comes another application…
– More overhead
– Redundant data
• Inconsistency
• Update anomalies

Ways of solving (contd..)

Method 2
– Connect to 3 data sources & extract data
– Three different access mechanisms

Data access mechanisms

Direct access to databases (JDBC,ODBC,..etc)

Use of O/R mapping frameworks (Hibernate,
Ibatis,...)

Enterprise Java Beans (EJBs)

CORBA

Custom APIs

Positioning of data access code..

Application developers like to deal with
business process related logic

Changes in data source configuration

Should be transparent to application logic

Should have minimal (if not any) effect on business
logic

Method 2
Concerns
− Data access code VS business logic implementation
− Difficult to reuse
− Difficult to maintain
− Difficult to test
− Error prone

Ways of solving... (contd)
Method 3
− Single layer to fulfill enterprise data access
requirements (Data Services)
Governed by,
− More and more data being generated
− Growing demand for consolidated, consistent
information
− Mashups
− Interoperability & standards

Data Services?
Tell me about it...

Data Service ?
Well defined request/response format
Encapsulates data oriented logic
Loose coupling (application & data store)
Data store specific configurations
Management & QoS features

WSO2 Data Services Server

Simple Example

Expose Employee Contact data in a MySQL
database table as a data service

Table Structure

GUI Wizard

Data Service Configuration
<data name="ContactInfoService">
<config>
<property name="org.wso2.ws.dataservice.driver">com.mysql.jdbc.Driver</property>
<property
name="org.wso2.ws.dataservice.protocol">jdbc:mysql://localhost:3306/dataservice_sample</property>
<property name="org.wso2.ws.dataservice.user">dsuser</property>
<property name="org.wso2.ws.dataservice.password">user123</property>
<property name="org.wso2.ws.dataservice.minpoolsize">1</property>
<property name="org.wso2.ws.dataservice.maxpoolsize">5</property>
</config>
<query id="contactInfoQuery">
<sql>select firstName,lastName,extension,email from employees where lastName = ?</sql>
<param name="name" sqlType="STRING" />
<result element="Employees" rowName="ContactInfo">
<attribute name="LastName" column="lastName" />
<element name="FirstName" column="firstName" />
<element name="Extension" column="extension" />
<element name="Email" column="email" />
</result>
</query>
<operation name="getContactInformation">
<call­query href="contactInfoQuery" >
<with­param name="name" query­param="name" />
</call­query>
</operation>
</data>

Data Services Description Language

In-house developed language for writing data
services

Maps service requests to your SOA to queries
operating on your database objects (tables,
views, procedures & functions)

Maps query results to XML responses

Available online @
http://wso2.org/wiki/display/wsf/Data+Servic
es+and+Resources

WSDL for the service
http://<IP>:<PORT>/services/ContactInfoService?wsdl

How to access a data service?

Multiple Data Source support

Secure Channel

Transformation

Federation

Caching

High availability

Throttling

Architecture

Challenges

RDBMS – specific or generic JDBC drivers

Directories – specific drivers, API

Flat files, Spread sheets – different APIs

Different data types

Access control mechanisms

Architecture

Data Services are SOA equivalent of the Data
Access Object(DAO) Pattern

DS deal with different data sources similar to
what DAO does

But, DS operate on a different layer

How to access a data service?

Accessing a data service – Java Client

Accessing a data service – REST
http://198.18.191.140:9763/services/DataServic
eSample1/employeesByNumber/1001

Accessing a data service – Try It

Monitoring
– Monitor System statistics
– Running logs
– Message Tracing
– Dynamically configurable Logger
– Exposes statistics via JMX
– Dashboard – Google Gadgets

Use Case 1

A mashup/ javascript/ Google Gadget wants to
access data in a backend database

Use Case 2

Re-using existing Master Data

Use Case 2

Use Case 3

Master Data Update

Use Case 3

Use Case 4

Content filtering based on logged in user

Use Case 4

Use Case 5

Service enabling enterprise data

Use Case 6

Integrating with an external system

Use Case 6

Use Case 7

WSO2 Product Platform

That's lot of information...
Now I would like to try these out
myself. How do I get started?

How to get started?

Download binary distribution from
– http://wso2.org/projects/data-services-server/java

Latest is v2.0

Unzip
• Run bin/wso2server.sh (on Unix) or
bin/wso2server.bat (on Windows)
• Management console
– https://localhost:9443/carbon
– admin/admin

Help.. I messed it up...

How to get help?

Online forum(http://wso2.org/forum/404)

Mailing list (ds-java-user@wso2.org)

Active community of external users

Ample free documentation on wso2.org

If needed, we provided commercial support on
– Getting started
– Deployment
– Custom development
– Production support

I would like to have some
URLs for reference.

Useful references

WSO2 Oxygen Tank for Web Service Developers
– http://wso2.org

Data Services HOWTOs Page
– http://wso2.org/library/3183

WSO2 Data Services project page
– http://wso2.org/projects/data-services-server/java

Summary
•
Introduced WSO2 Data Services
•
Features
•
Use cases
•
Getting started

Thank you
sumedha@wso2.com
(on behalf of WSO2 DS team)