Another datasource for service layer unit testing - unit-testing

Question

After learning JUnit and experienced its benefits for both programmer and the project, I wanted now to unit test the service layer of each entities and test if each methods works properly.
As of now, I already have created a unit test for all of my service classes but the problem is that the datasource's data isn't suited for testing. Thus I have to created another database for service layer testing and configure the datasource for the unit test of the service layers. But the things is I don't know how to configure another datasource which only the src/test/java could access and couldn't be accessed upon production. I'm still new to SpringBoot and SpringData so I'm asking how to configure such requirements here.
As of now I have this application.properties configuration.
spring.datasource.url=<DatabaseURL>
spring.datasource.username=<DatabaseUsername>
spring.datasource.password=<DatabasePassword>
spring.datasource.driver-class-name=<DatabaseDriver>
// another datasource configuration
And here's a sample code for a service class. Which uses the application.properities - dataSource configuration.
#Service
public class FooService {
#PersistenceContext
private EntityManager entityManager;
public List<Foo> findAllByFooForm(FooForm fooForm) {
// JPA CriteriaBuilder query accroding to FooForm
return entityManager.createQuery(query).getResultList();
}
}
Finally, here's a sample code for unit test of a service class.
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
public class FooServiceTest {
#AutoWired
private FooService fooService
#Test
public void testFindAllByFooForm() {
// Test statements
}
}

Answer 1

There are a few approaches which can be combined to give you good control over this.
First of all, if you create src/test/resources/application.properties, then that will only be available on the classpath during testing. It will override any properties that you have defined in src/main/resouces/application.properties.
If you are using an in-memory database to support those tests, then you can ensure that different import.sql files are loaded, through the use of the following property:
spring.jpa.properties.hibernate.hbm2ddl.import_files=import-test1.sql
That annotation takes a comma-separated list of import scripts, so you can have a base set of data loaded by one script and additional (test-specific perhaps) data loaded by others.
If you wish to connect to a different database in each test, or cause different import scripts to be used, then you can use profiles to trigger this. If you create a properties file application-test1.properties, then the test itself can cause that to be loaded using the annotation: #ActiveProfiles({"test1"}).