How to configure mutliple transaction managers with Spring + DBUnit + JUnit

Question

In a nutshell

My command line Java application copies data from one datasource to another without using XA. I have configured two separate datasources and would like a JUnit test that can rollback data on both datasources. I use DBUnit to load data into the "source" database, but I cannot get this to rollback. I can get the "target" datasource to rollback.

My Code

Given this config...

<tx:annotation-driven />

<!-- note the default transactionManager name on this one -->
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource"     ref="dataSourceA" />
</bean>

<bean id="transactionManagerTarget" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource"     ref="dataSourceB" />
</bean>

and this code...

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations={"classpath:resources/spring-context.xml",
                                "classpath:resources/spring-db.xml"})  
@Transactional
@TransactionConfiguration(transactionManager = "transactionManagerTarget", defaultRollback = true) 
public class MyIntegrationTest {

    @Autowired
    private MyService service;

    @Autowired
    @Qualifier("dataSourceA")
    private DataSource dataSourceA;

    private IDataSet loadedDataSet;

    /**
     * Required by DbUnit
     */
    @Before
    public void setUp() throws Exception {
        SybaseInsertIdentityOperation.TRUNCATE_TABLE.execute(getConnection(), getDataSet());
        SybaseInsertIdentityOperation.INSERT.execute(getConnection(), getDataSet());
    }

    /**
     * Required by DbUnit
     */
    protected IDataSet getDataSet() throws Exception {
        loadedDataSet = DbUnitHelper.getDataSetFromFile(getConnection(), "TestData.xml");
        return loadedDataSet;
    }

    /**
     * Required by DbUnit
     */
    protected IDatabaseConnection getConnection() throws Exception{
        return new DatabaseConnection(dataSourceA.getConnection());
    }   

    @Test
    public void testSomething() {

        // service.doCopyStuff();

    }

}

The problem as I see it, is that @TransactionConfiguration only states the target datasource for enabling a rollback. DBUnit is being passed dataSourceA explicitly and is picking up the default transaction manager named transactionManager (I'm not sure how) which has not been told to rollback.

Question

How can I tell both transaction managers to rollback?

Can I use a single transaction manager when my datasources do not support XA transactions?

Note: The application does not require a transaction manager on dataSourceA when running in production as it will only be read-only. This issue is for my tests classes only.

Answer 1

A possible workaround would be to introduce a helper bean annotated as @Transactional("transactionManagerTarget") and leave your test annotated as @Transactional("transactionManager"), configuring both with defaultRollback = true. Your test would then have to call the helper bean, which in turn would call your service bean under test. This should cause the transaction around your service to roll back, then the transaction around DBUnit.

It's a bit messy, though.

Other possible approaches:

• Using an in-memory database such as H2 instead of your production database- you could configure this to drop all of its data when required.
• Allow DBUnit to commit, and have a compensating transaction in your tear-down method to clear the data out.