SpringBoot JPA 多数据源的使用

怼烎@ 2022-06-04 07:52 242阅读 0赞

# SpringBoot JPA 多数据源的使用 #

参考: [http://gitbook.cn/gitchat/column/59f5daa149cd4330613605ba/topic/59f6a809a5beea6a3fd8a7f2][http_gitbook.cn_gitchat_column_59f5daa149cd4330613605ba_topic_59f6a809a5beea6a3fd8a7f2]

## 多数据源的支持 ##

在项目开发中,常常需要在一个项目中使用多个数据源,因此需要配置Spring data jpa对多数据源的使用.

一般分为以下三步:

1.  配置多数据源
2.  不同源的repsitory放入不同的包路径
3.  声明不同包路径下使用不同的数据源,事物支持

## 第一步:配置两个数据源的连接属性 ##

其中 application.properties 配置如下:

################ dataSource START #################
    #primary
    spring.primary.datasource.url=jdbc:mysql://localhost:3306/test1
    spring.primary.datasource.username=root
    spring.primary.datasource.password=root
    spring.primary.datasource.driver-class-name=com.mysql.jdbc.Driver
    
    #secondary
    spring.secondary.datasource.url=jdbc:mysql://localhost:3306/test2
    spring.secondary.datasource.username=root
    spring.secondary.datasource.password=root
    spring.secondary.datasource.driver-class-name=com.mysql.jdbc.Driver
    
    spring.jpa.properties.hibernate.hbm2ddl.auto=update
    spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
    spring.jpa.show-sql= true
    
    ############# dataSource END #############

## 第二步: 读取两个数据源，： ##

/** * @author itguang * @create 2017-12-07 16:22 **/
    @Configuration
    public class DataSourceConfig { 
    
    
        @Bean(name = "primaryDataSource")
        @Primary
        @Qualifier("primaryDataSource")
        @ConfigurationProperties(prefix = "spring.primary.datasource")
        public DataSource primaryDatasource() {
            return DataSourceBuilder.create().build();
        }
    
        @Bean(name = "secondaryDataSource")
        @Qualifier("secondaryDataSource")
        @ConfigurationProperties(prefix = "spring.secondary.datasource")
        public DataSource secondaryDataSource() {
            return DataSourceBuilder.create().build();
        }
    
    
    }

## 第三步: 将数据源注入到 Factory，配置 repository、domian 的位置,构建两个 实体管理器 EntityManager ##

/** * 将数据源注入到 实体管理器工厂，配置 repository、domian 的位置 * * @author itguang * @create 2017-12-07 16:35 * **/
    
    @Configuration
    @EnableTransactionManagement
    @EnableJpaRepositories(
            entityManagerFactoryRef = "entityManagerFactoryPrimary",//配置连接工厂 entityManagerFactory
            transactionManagerRef = "transactionManagerPrimary", //配置 事物管理器 transactionManager
            basePackages = {
       "com.itguang.springbootmultidatasource.repository.test1"}//设置dao（repo）所在位置
    )
    public class PrimaryConfig { 
    
        @Autowired
        private JpaProperties jpaProperties;
    
        @Autowired
        @Qualifier("primaryDataSource")
        private DataSource primaryDataSource;
    
    
        /** * * @param builder * @return */
        @Bean(name = "entityManagerFactoryPrimary")
        @Primary
        public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder) {
    
            return builder
                    //设置数据源
                    .dataSource(primaryDataSource)
                    //设置数据源属性
                    .properties(getVendorProperties(primaryDataSource))
                    //设置实体类所在位置.扫描所有带有 @Entity 注解的类
                    .packages("com.itguang.springbootmultidatasource.domain")
                    // Spring会将EntityManagerFactory注入到Repository之中.有了 EntityManagerFactory之后,
                    // Repository就能用它来创建 EntityManager 了,然后 EntityManager 就可以针对数据库执行操作
                    .persistenceUnit("primaryPersistenceUnit")
                    .build();
    
        }
    
        private Map<String, String> getVendorProperties(DataSource dataSource) {
            return jpaProperties.getHibernateProperties(dataSource);
        }
    
        /** * 配置事物管理器 * * @param builder * @return */
        @Bean(name = "transactionManagerPrimary")
        @Primary
        PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
            return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
        }
    
    
    }

## 第四步:测试 ##

@RunWith(SpringRunner.class)
    @SpringBootTest
    public class SpringbootMultiDatasourceApplicationTests { 
    
        @Resource
        private UserTest1Repository userTest1Repository;
        @Resource
        private UserTest2Repository userTest2Repository;
    
        @Test
        public void testSave() throws Exception {
            Date date = new Date();
            DateFormat dateFormat = DateFormat.getDateTimeInstance(DateFormat.LONG, DateFormat.LONG);
            String formattedDate = dateFormat.format(date);
    
            userTest1Repository.save(new User("aa", "aa123456","aa@126.com", "aa",  formattedDate));
            userTest2Repository.save(new User("cc", "cc123456","cc@126.com", "cc",  formattedDate));
    
        }
    
        @Test
        public void contextLoads() {
        }
    
    }

> 实体类和respoitory实现请参考源代码.
> 
> [https://github.com/itguang/gitbook-smile/tree/master/springboot-multi-datasource][https_github.com_itguang_gitbook-smile_tree_master_springboot-multi-datasource]

[http_gitbook.cn_gitchat_column_59f5daa149cd4330613605ba_topic_59f6a809a5beea6a3fd8a7f2]: http://gitbook.cn/gitchat/column/59f5daa149cd4330613605ba/topic/59f6a809a5beea6a3fd8a7f2
[https_github.com_itguang_gitbook-smile_tree_master_springboot-multi-datasource]: https://github.com/itguang/gitbook-smile/tree/master/springboot-multi-datasource