redis 事务与 jdbc 事务一起

Question

In our application we are using both MySQL server and Redis databases. we use Redis as a database and not just a cache. we use both of them in a service method and I want to make the method @Transactional to let the spring manages my transactions. Hence if in the middle of an transactional method a RuntimeException is thrown all works on both Redis and MySQL are rolled back. I have followed the spring docs and configured my @SpringBootApplication class as following:

@SpringBootApplication
@EnableTransactionManagement
public class TransactionsApplication {

    @Autowired
    DataSource dataSource;

    public static void main(String[] args) {
        SpringApplication.run(TransactionsApplication.class, args);
    }

    @Bean
    public StringRedisTemplate redisTemplate() {
        StringRedisTemplate template = new StringRedisTemplate(redisConnectionFactory());
        // explicitly enable transaction support
        template.setEnableTransactionSupport(true);
        return template;
    }

    @Bean
    public LettuceConnectionFactory redisConnectionFactory() {
        return new LettuceConnectionFactory(new RedisStandaloneConfiguration("localhost", 6379));
    }

    @Bean
    public PlatformTransactionManager transactionManager() throws SQLException, IOException {
        return new DataSourceTransactionManager(dataSource);
    }
}

and this is my service method:

@Service
@RequiredArgsConstructor
@Slf4j
public class FooService {

   private final StringRedisTemplate redisTemplate;
   private final FooRepository fooRepository;

   @Transactional            
   public void bar() {

       Foo foo = Foo.builder()
               .id(1001)
               .name("fooName")
               .email("foo@mail.com")
               .build();
       fooRepository.save(foo);

       ValueOperations<String, String> values = redisTemplate.opsForValue();
       values.set("foo-mail", foo.getEmail());

   }

However after the test method of TestService is called there is no user in MySQL db and I think it's because there is no active transaction for it.Is there any solution for this problem? Should I use spring ChainedTransactionManager class and then how? or I can only manage Redis transactions manually through MULTI ?

Answer 1

After playing around with FooService class I found that using @Transactional in a service method that is intended to work with Redis and specially read a value from Redis (which I think most service methods are supposed to read some value from DB) is somehow useless since any read operation would result a null value and that is because Redis queues all operations of a transaction and executes them at the end. Summing up, I think using MULTI and EXEC operations is more preferable since it gives more control to use data in Redis. After all, any suggestions to use Redis transactions is appreciated.