Spring Boot, Spring Data JPA,具有多个数据源

2022-08-31 22:10:43

我正在尝试使用Spring Boot和Spring Data JPA将每个@Repositories连接到不同的DataSource。http://xantorohara.blogspot.com/2013/11/spring-boot-jdbc-with-multiple.html,我使用了以下内容作为参考。以下是我使用的代码,试图使用Spring Data JPA实现类似的解决方案。

客户数据库配置.java(第一个数据源连接)

@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(第二个数据源)

@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;
    }
}

客户.java(型号)

@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;

....

订单.java (型号)

@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;

...

客户存储库.java

public interface CustomerRepository extends JpaRepository<Customer, Integer>{

}

订单存储库.java

public interface OrderRepository extends JpaRepository<Order, Integer> {

}

最后,应用.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;
        }
}

在启动期间,将引发以下异常

-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

可以在 GitHub 上找到该示例的完整代码(https://github.com/tonym2105/samples/tree/master/boot-multidb-sample)

提前感谢您的帮助。


答案 1

还有另一种方法可以通过使用@EnableAutoConfiguration和 application.properties 来拥有多个数据源。

基本上,将多个数据源配置信息放在 application.properties 上,并通过@EnableAutoConfiguration为第一个数据源自动生成默认设置(dataSource 和 entityManagerFactory)。但对于下一个数据源,创建 dataSource、entityManagerFactory 和 transactionManager,所有这些都是通过属性文件中的信息手动完成的。

下面是我设置两个数据源的示例。第一个数据源由@EnableAutoConfiguration只能为一个配置分配,而不能为多个配置分配该数据源。这将通过DataSourceTransactionManager生成“transactionManager”,它看起来像由注释生成的默认事务管理器。但是,我已经看到事务未在调度线程池的线程上开始问题,仅用于默认的DataSourceTransactionManager以及当有多个事务管理器时。因此,我通过JpaTransactionManager手动创建了transageManager,也用于第一个数据源,并分配了“transactionManager”bean名称和默认实体ManagerFactory。第一个数据源的 JpaTransactionManager 肯定解决了 ScheduledThreadPool 线程上奇怪的事务问题。

春季启动 1.3.0.发布的更新

我发现我以前使用@EnableAutoConfiguration的默认数据源的配置在查找带有Spring Boot 1.3版本的entityManagerFactory时出现问题。也许默认实体ManagerFactory不是由@EnableAutoConfiguration生成的,一次在我介绍我自己的事务管理器之后。所以现在我自己创建了entityManagerFactory。所以我不需要使用@EntityScan。所以看起来我越来越从设置中走出来,@EnableAutoConfiguration。

第二个数据源无需@EnableAutoConfiguration即可设置,并通过手动方式创建“另一个事务管理器”。

由于有多个事务管理器从 PlatformTransactionManager 扩展而来,因此我们应该指定在每个@Transactional注释上使用哪个事务管理器

默认存储库配置

@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;
    }
}

另一个存储库配置

@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());
    }
}

应用程序.属性

# 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

为@Transactional注释选择适当的事务管理器

第一个数据源的服务

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

   //

}

为其他数据源提供服务

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

   //

}

答案 2

这是我的解决方案。基于弹簧引导.1.2.5.发布。

应用程序.属性

first.datasource.driver-class-name=com.mysql.jdbc.Driver
first.datasource.url=jdbc:mysql://127.0.0.1:3306/test
first.datasource.username=
first.datasource.password=
first.datasource.validation-query=select 1

second.datasource.driver-class-name=com.mysql.jdbc.Driver
second.datasource.url=jdbc:mysql://127.0.0.1:3306/test2
second.datasource.username=
second.datasource.password=
second.datasource.validation-query=select 1

数据源配置.java

@Configuration
public class DataSourceConfig {
    @Bean
    @Primary
    @ConfigurationProperties(prefix="first.datasource")
    public DataSource firstDataSource() {
        DataSource ds =  DataSourceBuilder.create().build();
        return ds;
    }

    @Bean
    @ConfigurationProperties(prefix="second.datasource")
    public DataSource secondDataSource() {
        DataSource ds =  DataSourceBuilder.create().build();
        return ds;
    }
}

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