Why can't spring boot/data automagically configure multiple data sources?

I have a spring boot app that connects to two databases. Everything works fine.

My package structure looks like the following

- db
  - bar
    - BarDbConfig.java
    - domain
      - BarModel.java
    - repo
      - BarRepo.java
  - foo
    - FooDbConfig.java
    - domain
      - FooModel.java
    - repo
      - FooRepo.java

application.properties

spring.jpa.database=default
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
spring.jpa.hibernate.ddl-auto=none
spring.jpa.hibernate.naming.physical-strategy=org.hibernate.boot.model.naming.PhysicalNamingStrategyStandardImpl

#first db
bar.datasource.jdbc-url=jdbc:h2:C:\\Project\\com.example\\db3.data
bar.datasource.username=admin
bar.datasource.password=admin
bar.datasource.driver-class-name=org.h2.Driver

#second db
foo.datasource.jdbc-url=jdbc:h2:C:\\Project\\com.example\\db2.data
foo.datasource.username=admin
foo.datasource.password=admin
foo.datasource.driver-class-name=org.h2.Driver

BarDbConfig.java

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "barEntityManagerFactory",
        transactionManagerRef = "barTransactionManager"
)
public class BarDbConfig {

    @Bean
    @Primary
    @ConfigurationProperties(prefix = "bar.datasource")
    public DataSource barDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Primary
    @Bean
    public LocalContainerEntityManagerFactoryBean barEntityManagerFactory(
            EntityManagerFactoryBuilder builder,
            @Qualifier("barDataSource") DataSource dataSource
    ) {
        return builder.dataSource(dataSource)
                .packages(BarDbConfig.class.getPackage().getName())
                .persistenceUnit("barPersistenceUnit")
                .build();
    }

    @Primary
    @Bean
    public PlatformTransactionManager barTransactionManager(
            @Qualifier("barEntityManagerFactory") EntityManagerFactory entityManagerFactory) {
        return new JpaTransactionManager(entityManagerFactory);
    }
}

FooDbConfig.java

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "fooEntityManagerFactory",
        transactionManagerRef = "fooTransactionManager"
)
public class FooDbConfig {

    @Bean
    @ConfigurationProperties(prefix = "foo.datasource")
    public DataSource fooDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean
    public LocalContainerEntityManagerFactoryBean fooEntityManagerFactory(
            EntityManagerFactoryBuilder builder,
            @Qualifier("fooDataSource") DataSource dataSource
    ) {
        return builder.dataSource(dataSource)
                .packages(FooDbConfig.class.getPackage().getName())
                .persistenceUnit("fooPersistenceUnit")
                .build();
    }

    @Bean
    public PlatformTransactionManager fooTransactionManager(
            @Qualifier("fooEntityManagerFactory") EntityManagerFactory entityManagerFactory) {
        return new JpaTransactionManager(entityManagerFactory);
    }
}

However, I was wondering if all this boilerplate code was really necessary?

• Isn't there any way to remove all the LocalContainerEntityManagerFactoryBean and PlatformTransactionManager stuff?
• Is there any reason why it is necessary to provide all those explicit Qualifier-names?
• Can't spring boot find and autoconfigure the datasources by it self??
• What would be the absolute minimal code required to connect to two databases utilizing convention over configuration?