Configuring Oracle

The following sections describe how to replace the default H2 databases with Oracle.

Step 1: Setting up the Oracle database and user

Follow the steps below to set up a Oracle database.

1. Create a new database by using the Oracle database configuration assistant (dbca) or manually.

2. Make the necessary changes in the Oracle tnsnames.ora and listner.ora files in order to define addresses of the databases for establishing connections to the newly created database.

3. After configuring the .ora files, start the Oracle instance using the following command:

   $ sudo /etc/init.d/oracle-xe restart

4. Connect to Oracle using SQL*Plus as SYSDBA as follows:

   $ ./$<ORACLE_HOME>/config/scripts/sqlplus.sh sysadm/password as SYSDBA

5. Connect to the instance with the username and password using the following command:

   $ connect

6. As SYSDBA, create a database user and grant privileges to the user as shown below:

   Create user USER_NAME identified by password account unlock;
   grant connect to USER_NAME;
   grant create session, create table, create sequence, create trigger to USER_NAME;
   commit;

7. Exit from the SQL*Plus session by executing the quit command.

Step 2: Connecting the server to an Oracle database

Once you have setup the physical database as explained in the previous step, the next step is to enable the connectivity between your MB server and the database. This can be done by simply copying the relevant database drivers to your server, and then configuring the datasources in MB to link to the new database. See the instructions given below.

Copying the JDBC driver

1. Copy the Oracle JDBC libraries (for example: <ORACLE_HOME/jdbc/lib/ojdbc14.jar) to the <MB_HOME>/repository/components/lib/ directory.
2. Remove the old database driver from the <MB_HOME>/repository/components/dropins/ directory.

Setting up datasource configurations

The connection between physical databases and the server is established through datasources. The master-datasources.xml file (stored in the <MB_HOME>/repository/conf/datasources directory) is the default datasource configuration file that is shipped with WSO2 products. In the case of WSO2 MB, since we use two databases (Carbon database for registry/user management data and the MB-specific database for storing MB data), the master-datasources.xml file should contain two separate datasource configurations corresponding to the two databases.

If you check the default master-datasources.xml file in the product, you will see that the configurations point to the embedded H2 databases. The following instructions explain how you can divert the default configurations to point to the external MySQL database you created in step 1. 

Follow the steps given below to replace the MB-specific datasource configuration with a new connection to an Oracle database:

1. Open the <MB_HOME>/repository/conf/datasources/master-datasources.xml file. This is where datasources are configured to point to the databases used by the Message Broker. This file consists of commented out configurations for datasources. The datasource configuration for Oracle is among these. The changes made to this file must be done in both broker nodes.

2. Uncomment or add the following configuration into the master-datasources.xml file. Update the JDBC URL to correctly point to your database and enter the username and password for an Oracle database user with the proper permissions.
   

   <datasource>
          <name>ORACLE_DATA_SOURCE</name>
          <jndiConfig>
              <name>WSO2MBStoreDB</name>
          </jndiConfig>
          <definition type="RDBMS">
              <configuration>
                  <driverClassName>oracle.jdbc.driver.OracleDriver</driverClassName>
                  <url>jdbc:oracle:thin:@localhost:1521/orcl</url>
                  <maxActive>100</maxActive>
                  <maxWait>60000</maxWait>
                  <minIdle>5</minIdle>
                  <testOnBorrow>true</testOnBorrow>
                  <validationQuery>SELECT 1</validationQuery>
                  <validationInterval>30000</validationInterval>
                  <username>scott</username>
                  <password>tiger</password>
              </configuration>
          </definition>
   </datasource>

   The elements in the above datasource configurations are described below:

   Element	Description
   url	The URL of the database. The default port for a DB2 instance is 50000.
   username and password	The name and password of the database user
   driverClassName	The class name of the database driver
   maxActive	The maximum number of active connections that can be allocated  at the same time from this pool. Enter any negative value to denote an unlimited number of active connections.
   maxWait	The maximum number of milliseconds that the pool will wait (when there are no available connections) for a connection to be returned before throwing an exception. You can enter zero or a negative value to wait indefinitely.
   minIdle	The minimum number of active connections that can remain idle in the pool without extra ones being created, or enter zero to create none.
   testOnBorrow	The indication of whether objects will be validated before being borrowed from the pool. If the object fails to validate, it will be dropped from the pool, and another attempt will be made to borrow another.
   validationQuery	The SQL query that will be used to validate connections from this pool before returning them to the caller.
   validationInterval	The indication to avoid excess validation, and only run validation at the most, at this frequency (time in milliseconds). If a connection is due for validation, but has been validated previously within this interval, it will not be validated again.

   The default port for Oracle is 1521.

   For more information on other parameters that can be defined in the <MB_HOME>/repository/conf/datasources/master-datasources.xml file, see Tomcat JDBC Connection Pool.

3. Open the <MB_HOME>/repository/conf/broker.xml file. This is the root configuration file of Message Broker. The changes made to this file must be done in all the WSO2 Message Broker nodes.

4. In the broker.xml file we need to use the Oracle message store and Andes context store. To do this, uncomment or add the following configuration.
   

   ...
   <messageStore class="org.wso2.andes.store.rdbms.RDBMSMessageStoreImpl">
              <property name="dataSource">WSO2MBStoreDB</property>
   </messageStore>
   
   <andescontextStore class="org.wso2.andes.store.rdbms.RDBMSAndesContextStoreImpl">
              <property name="dataSource">WSO2MBStoreDB</property>
   </andescontextStore>

   The elements in the above configuration are described below.

   • Under class attribute of messageStore and andesContextStore elements fully qualified name of the respective implementation class should be defined. This implementation class will be used by MB to persist relevant information.

   • Property elements are used to define different properties to be used by each store. Minimal required property to start each store is the dataSource property. Depending on the implementation required properties may differ.

Step 3: Creating the database tables

To create the database tables, connect to the database that you created earlier and run the following scripts in SQL*Plus:

1. To create tables in the MB-specific database, use the below script:

   SQL> @$<MB_HOME>/dbscripts/oracle.sql

2. Restart the server.

   You can create database tables automatically when starting the product for the first time by using the -Dsetup parameter as follows:

   • For Windows: <MB_HOME>/bin/wso2server.bat -Dsetup

   • For Linux: <MB_HOME>/bin/wso2server.sh -Dsetup