java - 如何从一个数据源读取对象并使用 Spring 数据写入另一个数据源？

Question

我有一个配置类:

@SpringBootConfiguration
    @ComponentScan(basePackages = "vap")

    public class AppConfig {


        Logger logger = LoggerFactory.getLogger(this.getClass());
        public AppConfig() {
        }

        @Bean
        public ServerRuntime runtime() {
            ServerRuntime runtime = ServerRuntime.builder().addConfig("cayenne-project.xml").build();
            return runtime;
        }

        @Bean
        public ObjectContext getContext(@Autowired ServerRuntime serverRuntime) {
            return serverRuntime.newContext();
        }


        @Bean(name = "pgDataSource")
        public DataSource getDataSource() {
            Properties props = new Properties();
            props.setProperty("user", "postgres");
            props.setProperty("password", "");
            PoolConfiguration configuration = new PoolProperties();
            configuration.setDbProperties(props);
            configuration.setUrl("jdbc:postgresql://localhost/mikro00");
            configuration.setDriverClassName("org.postgresql.Driver");
            DataSource dataSource = new org.apache.tomcat.jdbc.pool.DataSource(configuration);
            return dataSource;
        }

        @Bean(name = "hsqldbDataSource")
        public DataSource getHSQLDataSource() {
            Properties props = new Properties();
            props.setProperty("user", "sa");
            props.setProperty("password", "");


            PoolConfiguration configuration = new PoolProperties();
            configuration.setDbProperties(props);
            configuration.setUrl("jdbc:h2:file:./outbase");
            configuration.setDriverClassName("org.h2.Driver");
            DataSource dataSource = new org.apache.tomcat.jdbc.pool.DataSource(configuration);
            return dataSource;
        }


    }

我的 PGConfig.java

@Configuration
@EnableTransactionManagement
public class PGConfig {

    @Primary
    @Bean(name = "entityManagerFactoryPG")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier(value = "pgDataSource") DataSource dataSource) {
        LocalContainerEntityManagerFactoryBean vap = builder.dataSource(dataSource)
                .packages("vap")
                .build();
        JpaVendorAdapter jpaVendorAdapter = new HibernateJpaVendorAdapter();
        vap.setJpaVendorAdapter(jpaVendorAdapter);
        return vap;
    }

    @Primary
    @Bean(name = "transactionManagerPG")
    public PlatformTransactionManager transactionManager(
            @Qualifier("entityManagerFactory") EntityManagerFactory
                    entityManagerFactory
    ) {
        return new JpaTransactionManager(entityManagerFactory);
    }

}

我的H2Config.java

@Configuration
@EnableTransactionManagement
public class H2Config {

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

    @Primary
    @Bean(name = "entityManagerFactory")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier(value = "hsqldbDataSource") DataSource dataSource){
        LocalContainerEntityManagerFactoryBean vap = builder.dataSource(dataSource)
                .packages("vap")
                .build();
        JpaVendorAdapter jpaVendorAdapter = new HibernateJpaVendorAdapter();
        vap.setJpaVendorAdapter(jpaVendorAdapter);
        return vap;

    }

    @Primary
    @Bean(name = "transactionManagerH2")
    public PlatformTransactionManager transactionManager(
            @Qualifier("entityManagerFactory") EntityManagerFactory
                    entityManagerFactory
    ) {
        return new JpaTransactionManager(entityManagerFactory);
    }

}

客户端存储库

@Repository
public interface KlientRepository extends CrudRepository<Klient,Integer> {
}

如何从一个存储库读取客户端并写入另一个存储库。我需要从 PG 读取数据，处理数据并保存到 h2。我找不到如何使用不同数据源的两个存储库对象，或者只是使用具体数据源创建存储库对象

Answer 1

您的代码中几乎包含了所有内容，您只需要进行一些微调即可

1. 使用 Datasource、EntityManagerFactory 和 TransactionManager 的 bean 声明创建两个配置类
2. 将两者之一标记为主
3. 创建两个模型类(每个数据库模型一个)
4. 在两个不同的包中创建两个 Repository 类**(非常重要)**
5. 在您的服务类中自动连接两个存储库，从一个数据库读取、操作并保存到另一个数据库。

代码中唯一缺少的是您需要告诉 Spring 哪个 Repository 类应该使用哪个 EntityManager/Datasource(因为您有两个)。这可以通过注释@EnableJpaRepositories(basepackages=...)来完成。在每个配置类上使用此注释，并使用 basePackages 指示您的存储库类