SpringBoot实现多租户架构

@Entity
@Table(schema = "#{tenant.schema}")
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    // 其他属性和方法...
}

// Hibernate多租户策略配置
@Bean
public MultiTenantConnectionProvider multiTenantConnectionProvider() {
    return new AbstractMultiTenantConnectionProvider() {
        @Override
        protected ConnectionProvider getAnyConnectionProvider() {
            // 返回通用的数据库连接提供者
        }

        @Override
        protected ConnectionProvider selectConnectionProvider(String tenantIdentifier) {
            // 根据租户ID切换数据库连接
        }
    };
}

@Bean
public CurrentTenantResolver currentTenantResolver() {
    return new CurrentTenantResolver() {
        @Override
        public String resolveCurrentTenantIdentifier() {
            // 从上下文中获取当前租户ID
        }

        @Override
        public boolean validateExistingCurrentSessions() {
            return true;
        }
    };
}

@Entity
@Table(name = "#{tenant.tablePrefix}_users")
public class User {
    // ...
}

// 自定义实体扫描配置
@Configuration
@ComponentScan(basePackages = {"com.example.entity"})
public class EntityScanConfig implements BeanClassLoaderAware, EntityManagerFactoryBuilderCustomizer {

    private ClassLoader classLoader;

    @Override
    public void customize(EntityManagerFactoryBuilder builder) {
        // 注入租户ID到实体扫描过程中
        builder.persistenceUnitRootLocation(new ClassPathResource("META-INF/persistence.xml"));
        builder.namingStrategy(new CustomNamingStrategy(classLoader));
    }

    // 实现自定义命名策略
    public class CustomNamingStrategy extends ImprovedNamingStrategy {
        // 根据租户ID动态生成表名
    }
}

@Configuration
public class DataSourceConfig {

    @Bean
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSourceProperties dataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    @Primary
    public DataSource dataSource(DataSourceProperties properties, @Qualifier("multiTenantRoutingDataSource") DataSource multiTenantDataSource) {
        HikariDataSource dataSource = properties.initializeDataSourceBuilder().type(HikariDataSource.class).build();
        if (multiTenantDataSource instanceof HikariDataSource) {
            ((HikariDataSource) dataSource).addHealthCheckRegistry(((HikariDataSource) multiTenantDataSource).getHealthCheckRegistry());
        }
        return dataSource;
    }

    @Bean
    public DataSource multiTenantRoutingDataSource(DataSource defaultDataSource) {
        Map<Object, Object> targetDataSources = new ConcurrentHashMap<>();
        DynamicRoutingDataSource dataSource = new DynamicRoutingDataSource();
        dataSource.setDefaultTargetDataSource(defaultDataSource);
        dataSource.setTargetDataSources(targetDataSources);
        dataSource.afterPropertiesSet();
        return dataSource;
    }

    // 添加租户数据源
    public void addTenantDataSource(String tenantId, DataSource dataSource) {
        ((DynamicRoutingDataSource) multiTenantRoutingDataSource).addDataSource(tenantId, dataSource);
    }

    // 租户数据源切换AOP
    @Aspect
    @Component
    public class TenantDataSourceAspect {
        @Before("@annotation(com.example.annotation.ChangeTenant)")
        public void changeDataSource(JoinPoint joinPoint, ChangeTenant annotation) {
            // 获取当前租户ID并切换数据源
        }
    }
}