Autowire repositories from similar tables in different datasources - spring-boot

Question

I have two versions of the same application. They are using similar database schemas. I want to run a junit test that compares two tables on both sides. I am using Springboot and JPA. I can autowire both datasources in the same test. I can autowire a CrudRepository for one of the tables in the primary datasource. But how can I autowire a similar repository for the same table that is sitting on the second datasource, at the same time in the same Junit test? I would like to do something like this on the same class:
#Autowired( Datasource="primarydatasource")
CustomerRepository fistCustomerRepository;
#Autowired( Datasource="seconddatasource")
CustomerRepository secondCustomerRepository;
I have checked many tutorials and answers here, but I have not found a clear example on this.

Answer 1

Using multiple datasources with Spring Boot

Answer 2

You can create two EntityManager
#Bean("em1")
public LocalContainerEntityManagerFactoryBean em1(
EntityManagerFactoryBuilder builder) {
return builder
.dataSource(customDataSource1())
.packages(DataSource.class)
.build();
}
#Bean("em2")
public LocalContainerEntityManagerFactoryBean em2(
EntityManagerFactoryBuilder builder) {
return ...;
}
Then you can inject the entity manager in you repository
#Repository
class CustomerRepositoryOracle{
#PersistenceContext(name="em1")
private EntityManager entityManager;
}
#Repository
class CustomerRepositoryPostgreSQL{
#PersistenceContext(name="em2")
private EntityManager entityManager;
}