在 Spring Boot 应用程序中的多个数据库中未创建表

java hibernate spring spring-data-jpa spring-boot

2022-09-04 23:18:30

我正在研究弹簧启动多租户应用程序。我已经配置了多个数据源，如下所示：

应用程序.属性

spring.multitenancy.datasource1.url=jdbc:mysql://localhost:3306/db1
spring.multitenancy.datasource1.username=root
spring.multitenancy.datasource1.password=****
spring.multitenancy.datasource1.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.hibernate.ddl-auto=update

spring.multitenancy.datasource2.url=jdbc:mysql://localhost:3306/db2
spring.multitenancy.datasource2.username=root
spring.multitenancy.datasource2.password=****
spring.multitenancy.datasource2.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.hibernate.ddl-auto=update

spring.multitenancy.datasource3.url=jdbc:mysql://localhost:3306/db3
spring.multitenancy.datasource3.username=root
spring.multitenancy.datasource3.password=****
spring.multitenancy.datasource3.driver-class-name=com.mysql.jdbc.Driver
spring.jpa.hibernate.ddl-auto=update

DataSourceBasedMultiTenantConnectionProviderImpl.java

@Component
public class DataSourceBasedMultiTenantConnectionProviderImpl extends AbstractDataSourceBasedMultiTenantConnectionProviderImpl {

    private static final long serialVersionUID = 8168907057647334460L;
    private static final String DEFAULT_TENANT_ID = "tenant_1";

    @Autowired
    private DataSource dataSource1;

    @Autowired
    private DataSource dataSource2;

    @Autowired
    private DataSource dataSource3;

    private Map<String, DataSource> map;

    @PostConstruct
    public void load() {
        map = new HashMap<>();
        map.put("tenant_1", dataSource1);
        map.put("tenant_2", dataSource2);
        map.put("tenant_3", dataSource3);
    }

    @Override
    protected DataSource selectAnyDataSource() {
        return map.get(DEFAULT_TENANT_ID);
    }

    @Override
    protected DataSource selectDataSource(String tenantIdentifier) {
        return map.get(tenantIdentifier);
    }
}

多租户属性.java

@ConfigurationProperties("spring.multitenancy")
public class MultitenancyProperties {

    @NestedConfigurationProperty
    private DataSourceProperties datasource1;

    @NestedConfigurationProperty
    private DataSourceProperties datasource2;

    @NestedConfigurationProperty
    private DataSourceProperties datasource3;

    public DataSourceProperties getDatasource1() {
        return datasource1;
    }

    public void setDatasource1(DataSourceProperties datasource1) {
        this.datasource1 = datasource1;
    }

    public DataSourceProperties getDatasource2() {
        return datasource2;
    }

    public void setDatasource2(DataSourceProperties datasource2) {
        this.datasource2 = datasource2;
    }

    public DataSourceProperties getDatasource3() {
        return datasource3;
    }

    public void setDatasource3(DataSourceProperties datasource3) {
        this.datasource3 = datasource3;
    }
}

MultiTenancyJpaConfiguration.java

@Configuration
@EnableConfigurationProperties(JpaProperties.class)
public class MultiTenancyJpaConfiguration {

    @Autowired
    private DataSource dataSource;

    @Autowired
    private JpaProperties jpaProperties;

    @Autowired
    private MultiTenantConnectionProvider multiTenantConnectionProvider;

    @Autowired
    private CurrentTenantIdentifierResolver currentTenantIdentifierResolver;

    @Bean
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder) {
        Map<String, Object> hibernateProps = new LinkedHashMap<>();
        hibernateProps.putAll(jpaProperties.getHibernateProperties(dataSource));

        hibernateProps.put(Environment.MULTI_TENANT, MultiTenancyStrategy.DATABASE);
        hibernateProps.put(Environment.MULTI_TENANT_CONNECTION_PROVIDER, multiTenantConnectionProvider);
        hibernateProps.put(Environment.MULTI_TENANT_IDENTIFIER_RESOLVER, currentTenantIdentifierResolver);
        hibernateProps.put(Environment.DIALECT, "org.hibernate.dialect.MySQLDialect");

        return builder.dataSource(dataSource).packages(HotelEntity.class.getPackage().getName()).properties(hibernateProps).jta(false).build();
    }
}

应用程序启动器

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableConfigurationProperties(MultitenancyProperties.class)
public class Application {

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

当我运行引导应用程序时，所有表都是仅在第一个数据源中创建的。
1）如何在应用程序启动时在所有数据源中创建表？
2）如何查看每个数据源的连接打开/关闭？
3）有没有更好的方法来配置多租户应用程序使用弹簧启动以获得更好的性能？

答案 1

正如@Alex所说，你需要不同的EntityManagers，TransactionManager和Datasources。以下是我该怎么做

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "dataSource1EntityManagerFactory",
    transactionManagerRef = "dataSource1TransactionManager",
    basePackageClasses = dataSource1Repository.class)
public class DataSource1Config extends SqlConfig{// Put all common code in base class SqlConfig. If not remove it

    @Bean
    @Primary
    public DataSource dataSource1() {
        //create dataSource using MultitenancyProperties::getDataSource1
    }

    @Primary
    @Bean(name = "dataSource1TransactionManager")
    PlatformTransactionManager dataSource1TransactionManager(EntityManagerFactory dataSource1EntityManagerFactory) {
        JpaTransactionManager txManager = new JpaTransactionManager();
        txManager.setEntityManagerFactory(dataSource1EntityManagerFactory);
        return txManager;
    }

    @Primary
    @Bean(name = "dataSource1EntityManagerFactory")
    LocalContainerEntityManagerFactoryBean dataSource1EntityManagerFactory() {
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource1());
        em.setPackagesToScan(dataSource1Repository.class.getPackage().getName(), dataSource1ModelClass.class.getPackage().getName());
        em.setPersistenceUnitName("dataSource1Db");

        HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        vendorAdapter.setGenerateDdl(false);
        em.setJpaVendorAdapter(vendorAdapter);
        return em;
    }
}

您可以像这样创建另外两个类。请记住只在数据源，事务管理器和实体管理器（无论哪一个）上使用。另一个警告是，确保存储库类位于所有三个数据库的不同包中。@Primary

答案 2

尝试添加以下属性：

spring.jpa.generate-ddl=true