Java – Spring Boot, Spring Data JPA with multiple DataSources

javajpaspringspring-bootspring-data

I'm trying to connect each @Repositories to different DataSource(s) with Spring Boot and Spring Data JPA. I used the following, http://xantorohara.blogspot.com/2013/11/spring-boot-jdbc-with-multiple.html, as a referrence. Here is the code I am using in an attempt to implement a similar solution using Spring Data JPA.

CustomerDbConfig.java(First data source connection)

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "orderEntityManager",
        transactionManagerRef = "orderTransactionManager",
        basePackages = {"com.mm.repository.customer"})
public class CustomerDbConfig {

    @Bean(name = "customerEntityManager")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(){
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource());
        em.setPackagesToScan(new String[] {"com.mm.domain.customer"});

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(additionalJpaProperties());
        em.setPersistenceUnitName("customerPersistence");
        em.setPackagesToScan("com.mm.domain.customer");

        return em;
    }

    Properties additionalJpaProperties(){
        Properties properties = new Properties();
        properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
        properties.setProperty("hibernate.show_sql", "true");

        return properties;
    }

    @Bean
    public DataSource dataSource(){
        return DataSourceBuilder.create()
                .url("jdbc:h2:mem:customer:H2")
                .driverClassName("org.h2.Driver")
                .username("sa")
                .password("")
                .build();
    }   

    @Bean(name = "customerTransactionManager")
    public PlatformTransactionManager transactionManager(EntityManagerFactory emf){
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);

        return transactionManager;
    }
}

CustomerDbConfig.java (Second data source)

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "orderEntityManager",
        transactionManagerRef = "orderTransactionManager",
        basePackages = {"com.mm.repository.customer"})
public class CustomerDbConfig {

    @Bean(name = "customerEntityManager")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(){
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource());
        em.setPackagesToScan(new String[] {"com.mm.domain.customer"});

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(additionalJpaProperties());
        em.setPersistenceUnitName("customerPersistence");
        em.setPackagesToScan("com.mm.domain.customer");

        return em;
    }

    Properties additionalJpaProperties(){
        Properties properties = new Properties();
        properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
        properties.setProperty("hibernate.show_sql", "true");

        return properties;
    }

    @Bean
    public DataSource dataSource(){
        return DataSourceBuilder.create()
                .url("jdbc:h2:mem:customer:H2")
                .driverClassName("org.h2.Driver")
                .username("sa")
                .password("")
                .build();
    }   

    @Bean(name = "customerTransactionManager")
    public PlatformTransactionManager transactionManager(EntityManagerFactory emf){
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);

        return transactionManager;
    }
}

Customer.java (model)

@Entity
@Table(name = "customer")
@Data
@EqualsAndHashCode(exclude = {"id"})
public class Customer {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column(name = "name", nullable = false)
    private String name;

    @Column(name = "age", nullable = false)
    private Integer age;

....

Order.java (model)

@Entity
@Table(name = "order")
@Data
@EqualsAndHashCode(exclude = {"id"})
public class Order {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column(name = "code", nullable = false)
    private Integer code;

    @Column(name = "quality", nullable = false)
    private Integer quality;

…

CustomerRepository.java

public interface CustomerRepository extends JpaRepository<Customer, Integer>{

}

OrderRepository.java

public interface OrderRepository extends JpaRepository<Order, Integer> {

}

Finally, Application.java

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class Application extends SpringApplication{

       public static void main(String[] args) {
            SpringApplication.run(Application.class, args);
        }

        @Bean
        public ServletRegistrationBean h2Console() {
            ServletRegistrationBean reg = new ServletRegistrationBean(new WebServlet(), "/console/*");
            reg.setLoadOnStartup(1);
            return reg;
        }
}

During start the following exceptions are thrown:

-10-10 15:45:24.757 ERROR 1549 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'customerTransactionManager' defined in class path resource [com/mm/boot/multidb/CustomerConfig.class]: Unsatisfied dependency expressed through constructor argument with index 0 of type [javax.persistence.EntityManagerFactory]: : No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:747)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:462)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1095)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:990)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:952)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:941)
    at com.mm.boot.multidb.Application.main(Application.java:17)
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:974)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:862)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:811)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:739)
    ... 18 common frames omitted

Exception in thread "main" org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'customerTransactionManager' defined in class path resource [com/mm/boot/multidb/CustomerConfig.class]: Unsatisfied dependency expressed through constructor argument with index 0 of type [javax.persistence.EntityManagerFactory]: : No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:747)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:462)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1095)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:990)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:952)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:941)
    at com.mm.boot.multidb.Application.main(Application.java:17)
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:974)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:862)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:811)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:739)
    ... 18 more

Full code for the sample can be found on GitHub (https://github.com/tonym2105/samples/tree/master/boot-multidb-sample)

Thank you in advance for the help.

Best Answer

There is another way to have multiple dataSources by using @EnableAutoConfiguration and application.properties.

Basically put multiple dataSource configuration info on application.properties and generate default setup (dataSource and entityManagerFactory) automatically for first dataSource by @EnableAutoConfiguration. But for next dataSource, create dataSource, entityManagerFactory and transactionManager all manually by the info from property file.

Below is my example to setup two dataSources. First dataSource is setup by @EnableAutoConfiguration which can be assigned only for one configuration, not multiple. And that will generate 'transactionManager' by DataSourceTransactionManager, that looks default transactionManager generated by the annotation. However I have seen the transaction not beginning issue on the thread from scheduled thread pool only for the default DataSourceTransactionManager and also when there are multiple transaction managers. So I create transactionManager manually by JpaTransactionManager also for the first dataSource with assigning 'transactionManager' bean name and default entityManagerFactory. That JpaTransactionManager for first dataSource surely resolves the weird transaction issue on the thread from ScheduledThreadPool.

Update for Spring Boot 1.3.0.RELEASE

I found my previous configuration with @EnableAutoConfiguration for default dataSource has issue on finding entityManagerFactory with Spring Boot 1.3 version. Maybe default entityManagerFactory is not generated by @EnableAutoConfiguration, once after I introduce my own transactionManager. So now I create entityManagerFactory by myself. So I don't need to use @EntityScan. So it looks I'm getting more and more out of the setup by @EnableAutoConfiguration.

Second dataSource is setup without @EnableAutoConfiguration and create 'anotherTransactionManager' by manual way.

Since there are multiple transactionManager extends from PlatformTransactionManager, we should specify which transactionManager to use on each @Transactional annotation

Default Repository Config

@Configuration
@EnableTransactionManagement
@EnableAutoConfiguration
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactory",
        transactionManagerRef = "transactionManager",
        basePackages = {"com.mysource.repository"})
public class RepositoryConfig {
    @Autowired
    JpaVendorAdapter jpaVendorAdapter;

    @Autowired
    DataSource dataSource;

    @Bean(name = "entityManager")
    public EntityManager entityManager() {
        return entityManagerFactory().createEntityManager();
    }

    @Primary
    @Bean(name = "entityManagerFactory")
    public EntityManagerFactory entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource);
        emf.setJpaVendorAdapter(jpaVendorAdapter);
        emf.setPackagesToScan("com.mysource.model");
        emf.setPersistenceUnitName("default");   // <- giving 'default' as name
        emf.afterPropertiesSet();
        return emf.getObject();
    }

    @Bean(name = "transactionManager")
    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager tm = new JpaTransactionManager();
        tm.setEntityManagerFactory(entityManagerFactory());
        return tm;
    }
}

Another Repository Config

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "anotherEntityManagerFactory",
        transactionManagerRef = "anotherTransactionManager",
        basePackages = {"com.mysource.anothersource.repository"})
public class AnotherRepositoryConfig {
    @Autowired
    JpaVendorAdapter jpaVendorAdapter;

    @Value("${another.datasource.url}")
    private String databaseUrl;

    @Value("${another.datasource.username}")
    private String username;

    @Value("${another.datasource.password}")
    private String password;

    @Value("${another.dataource.driverClassName}")
    private String driverClassName;

    @Value("${another.datasource.hibernate.dialect}")
    private String dialect;

    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource(databaseUrl, username, password);
        dataSource.setDriverClassName(driverClassName);
        return dataSource;
    }

    @Bean(name = "anotherEntityManager")
    public EntityManager entityManager() {
        return entityManagerFactory().createEntityManager();
    }

    @Bean(name = "anotherEntityManagerFactory")
    public EntityManagerFactory entityManagerFactory() {
        Properties properties = new Properties();
        properties.setProperty("hibernate.dialect", dialect);

        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource());
        emf.setJpaVendorAdapter(jpaVendorAdapter);
        emf.setPackagesToScan("com.mysource.anothersource.model");   // <- package for entities
        emf.setPersistenceUnitName("anotherPersistenceUnit");
        emf.setJpaProperties(properties);
        emf.afterPropertiesSet();
        return emf.getObject();
    }

    @Bean(name = "anotherTransactionManager")
    public PlatformTransactionManager transactionManager() {
        return new JpaTransactionManager(entityManagerFactory());
    }
}

application.properties

# database configuration
spring.datasource.url=jdbc:h2:file:~/main-source;AUTO_SERVER=TRUE
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.continueOnError=true
spring.datasource.initialize=false

# another database configuration
another.datasource.url=jdbc:sqlserver://localhost:1433;DatabaseName=another;
another.datasource.username=username
another.datasource.password=
another.datasource.hibernate.dialect=org.hibernate.dialect.SQLServer2008Dialect 
another.datasource.driverClassName=com.microsoft.sqlserver.jdbc.SQLServerDriver

Choose proper transactionManager for @Transactional annotation

Service for first datasource

@Service("mainService")
@Transactional("transactionManager")
public class DefaultDataSourceServiceImpl implements DefaultDataSourceService       
{

   //

}

Service for another datasource

@Service("anotherService")
@Transactional("anotherTransactionManager")
public class AnotherDataSourceServiceImpl implements AnotherDataSourceService 
{

   //

}