Expose data with Data Services

Introduction

This sample demonstrates how to expose some data stored in a database created via WSO2 storage server.

Prerequisites

Java Development Kit / JRE version 1.6.* or 1.7.*
Apache Ant 1.7.0 or later
Download WSO2 DSS.
Download WSO2 Developer Studio

Creating a data service

Create a Database, a privilege template and a database user using WSO2SS and attach the created user to the database,

Use WSO2 Developer Studio and create a data service using the following values.

Field	Example	Description
Driver Class	com.mysql.jdbc.Driver	This is the driver class of the database created via WSO2 SS.
JDBC URL	jdbc:mysql://localhost:3306/wso2DB_wso2_com	This is the url received from WSO2 SS after successful creation of a database.
User Name	user1_aJLNWWiS	The user name of a user created in WSO2 SS, and attached to the database created.
Password	user1	The password of the above user created in WSO2 SS, and attached to the database created.

The sample data service descriptor would be as follows.

<data enableBoxcarring="true" name="RDBMSSample" serviceNamespace="http://ws.wso2.org/dataservice/samples/rdbms_sample">   
	<config id="default">
	  // add the database driver of the relevant db instance created.
      <property name="org.wso2.ws.dataservice.driver">com.mysql.jdbc.Driver</property>
	  //add the database url recieved from Storage server.
      <property name="org.wso2.ws.dataservice.protocol">jdbc:mysql://localhost:3306/wso2DB_wso2_com</property>
	  //add a user to connecto to the database, which is already attached to the afore mentioned database via Storage Server.
      <property name="org.wso2.ws.dataservice.user">user1_aJLNWWiS</property>
	  //use the aforementioned users password. 	
      <property name="org.wso2.ws.dataservice.password">user1</property>
      <property name="org.wso2.ws.dataservice.minpoolsize">1</property>
      <property name="org.wso2.ws.dataservice.maxpoolsize">10</property>
      <property name="org.wso2.ws.dataservice.autocommit">false</property>
      <property name="org.wso2.ws.dataservice.validation_query"/>
   </config>

   //The sample Query.
   <query id="customersInBostonSQL" useConfig="default">
      <sql>select  * from Customers where city = 'Boston' and country = 'USA'</sql>
      <result element="customers" rowName="customer">
         <element column="customerName" name="customer-name" xsdType="string"/>
         <element column="contactLastName" name="contact-last-name" xsdType="string"/>
         <element column="contactFirstName" name="contact-first-name" xsdType="string"/>
         <element column="phone" name="phone" xsdType="string"/>
         <element column="city" name="city" xsdType="string"/>
         <element column="country" name="country" xsdType="string"/>
      </result>
   </query>

	//The sample dataservice.
	<operation name="customersInBoston">
      <call-query href="customersInBostonSQL"/>
   </operation>
</data>

Executing the sample

Group the created data service with a Carbon Application Project and create the Carbon Application Archive [CAR] and deploy in to the WSO2 Data Services Server.