Spring-Data-Jpa的使用（2）--多數據源配置

在使用spring-data-jpa時，若是要配置多數據源，通常爲如下三個步驟：

• 在配置文件配置多數據源
• 不一樣源的 repository 放入不一樣包路徑
• 聲明不一樣的包路徑下使用不一樣的數據源、事務支持

1.配置文件配置多數據源

---

spring.primary.datasource.url=jdbc:mysql://localhost:3306/test
spring.primary.datasource.username=root
spring.primary.datasource.password=root
spring.primary.datasource.driver-class-name=com.mysql.jdbc.Driver

spring.secondary.datasource.url=jdbc:mysql://localhost:3306/test1
spring.secondary.datasource.username=root
spring.secondary.datasource.password=root
spring.secondary.datasource.driver-class-name=com.mysql.jdbc.Driver

2.不一樣源的 repository 放入不一樣包路徑

---

3.聲明不一樣的包路徑下使用不一樣的數據源

---

將數據源注入到 Factory，配置 repository、domian 的位置，須要設置一個默認的數據源

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactoryPrimary",
        transactionManagerRef = "transactionManagerPrimary",
        basePackages = {"com.zb.boot.repository.primary"}//聲明路徑
)
public class PrimaryConfig {
    @Autowired
    private JpaProperties jpaProperties;
    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;
    public EntityManager entityManager(EntityManagerFactoryBuilder builder){
        return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
    }
    @Bean(name = "entityManagerFactoryPrimary")
    @Primary
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder){
        return builder.dataSource(primaryDataSource)
                .properties(getVendorProperties(primaryDataSource))
                .packages("com.zb.boot.model")//實體類的路徑
                .persistenceUnit("primaryPersistenceUnit")
                .build();
    }
    public Map<String, String> getVendorProperties(DataSource dataSource){
        return jpaProperties.getHibernateProperties(dataSource);
    }
    @Bean(name = "transactionManagerPrimary")
    @Primary
    PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder){
        return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
    }
}

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactorySecondary",
        transactionManagerRef="transactionManagerSecondary",
        basePackages= { "com.zb.boot.repository.secondary" })
public class SecondaryConfig {
    @Autowired
    private JpaProperties jpaProperties;

    @Autowired
    @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;

    @Bean(name = "entityManagerSecondary")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return entityManagerFactorySecondary(builder).getObject().createEntityManager();
    }

    @Bean(name = "entityManagerFactorySecondary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary (EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(secondaryDataSource)
                .properties(getVendorProperties(secondaryDataSource))
                .packages("com.zb.boot.model")
                .persistenceUnit("secondaryPersistenceUnit")
                .build();
    }

    private Map<String, String> getVendorProperties(DataSource dataSource) {
        return jpaProperties.getHibernateProperties(dataSource);
    }

    @Bean(name = "transactionManagerSecondary")
    PlatformTransactionManager transactionManagerSecondary(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
    }

}

讀取兩個配置源，構建兩個數據源：

@Configuration
public class DataSourceConfig {

    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    @ConfigurationProperties(prefix = "spring.primary.datasource")
    public DataSource primaryDataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    @Primary
    @ConfigurationProperties(prefix = "spring.secondary.datasource")
    public DataSource secondaryDataSource(){
        return DataSourceBuilder.create().build();
    }
}