Spring Boot 优雅实现多租户架构，so easy!

@RestController
public class TenantController {
    @GetMapping("/hello")
    public String hello(@RequestHeader("tenant-id") String tenantId) {
        return "Hello, " + tenantId;
    }
}

CREATE TABLE tenant (
    id BIGINT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(50) NOT NULL UNIQUE,
    description VARCHAR(255),
    created_time TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_time TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
);

@EnableGlobalMethodSecurity(prePostEnabled = true)
@Configuration
public class SecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
                .antMatchers("/api/tenant/**").hasRole("ADMIN")
                .anyRequest().authenticated()
                .and()
                .formLogin();
    }
    @Autowired
    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
        auth.userDetailsService(userDetailsService())
                .passwordEncoder(new BCryptPasswordEncoder())
                .and()
                .inMemoryAuthentication()
                .withUser("admin")
                .password(new BCryptPasswordEncoder().encode("123456"))
                .roles("ADMIN");
    }
}

@Configuration
public class DataSourceConfig {
    @Bean(name = "dataSourceA")
    @ConfigurationProperties(prefix = "spring.datasource.a")
    public DataSource dataSourceA() {
        return DataSourceBuilder.create().build();
    }
    @Bean(name = "dataSourceB")
    @ConfigurationProperties(prefix = "spring.datasource.b")
    public DataSource dataSourceB() {
        return DataSourceBuilder.create().build();
    }
    @Bean(name = "dataSourceC")
    @ConfigurationProperties(prefix = "spring.datasource.c")
    public DataSource dataSourceC() {
        return DataSourceBuilder.create().build();
    }
}

@Service
public class ProductService {
    @Autowired
    @Qualifier("dataSourceA")
    private DataSource dataSource;
    // ...
}

public class DynamicDataSource extends AbstractRoutingDataSource {
    @Override
    protected Object determineCurrentLookupKey() {
        return TenantContextHolder.getTenantId();
    }
}
@Configuration
public class DataSourceConfig {
    @Bean(name = "dataSource")
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource dataSource() {
        return DataSourceBuilder.create().type(DynamicDataSource.class).build();
    }
}

<!-- Spring Boot -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- Spring Cloud -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-dependencies</artifactId>
    <version>2020.0.3</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/appdb?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
    username: root
    password: 123456
mybatis:
  type-aliases-package: com.example.demo.model
  mapper-locations: classpath:mapper/*.xml
server:
  port: 8080
eureka:
  client:
    serviceUrl:
      defaultZone: http://localhost:8761/eureka/
management:
  endpoints:
    web:
      exposure:
        include: "*"

@Configuration
public class MultiTenantConfig {
    // 提供对应租户的数据源
    @Bean
    public DataSource dataSource(TenantRegistry tenantRegistry) {
        return new TenantAwareDataSource(tenantRegistry);
    }
    // 多租户Session工厂
    @Bean(name = "sqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory(DataSource dataSource)
            throws Exception {
        SqlSessionFactoryBean sessionFactory = new SqlSessionFactoryBean();
        sessionFactory.setDataSource(dataSource);
        return sessionFactory.getObject();
    }
    // 动态切换租户
    @Bean
    public MultiTenantInterceptor multiTenantInterceptor(TenantResolver tenantResolver) {
        MultiTenantInterceptor interceptor = new MultiTenantInterceptor();
        interceptor.setTenantResolver(tenantResolver);
        return interceptor;
    }
    // 注册拦截器
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(multiTenantInterceptor());
    }
    // 注册租户信息
    @Bean
    public TenantRegistry tenantRegistry() {
        return new TenantRegistryImpl();
    }
    // 解析租户ID
    @Bean
    public TenantResolver tenantResolver() {
        return new HeaderTenantResolver();
    }
}