Hystrix: Is the Hystrix conflicted with spring transaction?

[jordandandan]

I write a hystrix like this：
`public class HystrixCommandAdvice {

public Object runCommand(final ProceedingJoinPoint pjp) {
    return wrapWithHystrixCommnad(pjp).execute();
}

private HystrixCommand<Object> wrapWithHystrixCommnad(final ProceedingJoinPoint pjp) {

    return new HystrixCommand<Object>(setter()) {
        @Override
        protected Object run() throws Exception {
            try {
                return pjp.proceed();
            } catch (Throwable throwable) {
                throw (Exception) throwable;
            }
        }

        @Override
        protected Object getFallback() {
            Map<String,Object> map = new HashMap<String,Object>();
            map.put("msg", "system is wrong");
            if(this.isCircuitBreakerOpen()){
                logger.info("----------Hystrix circuit breaker Open！----");
                map.put("circuit breaker", "consume circuite breaker is open");
            }else{
                logger.info("----------Hystrix circuit breaker Close！----");
            }
            logger.info("------------Hystrix fallback!----------------");


            return map;
        }
    };

}

private HystrixCommand.Setter setter() {

    return HystrixCommand.Setter
            .withGroupKey(HystrixCommandGroupKey.Factory.asKey(groupName))
            .andCommandKey(HystrixCommandKey.Factory.asKey(commandName))
            .andCommandPropertiesDefaults(HystrixCommandProperties.Setter()
                    .withCircuitBreakerEnabled(Boolean.parseBoolean(withCircuitBreakerEnabled))
                    .withCircuitBreakerForceClosed(Boolean.parseBoolean(withCircuitBreakerForceClosed))
                    .withCircuitBreakerForceOpen(Boolean.parseBoolean(withCircuitBreakerForceOpen))
                    .withCircuitBreakerErrorThresholdPercentage(Integer.parseInt(withCircuitBreakerErrorThresholdPercentage))
                    .withCircuitBreakerRequestVolumeThreshold(Integer.parseInt(withCircuitBreakerRequestVolumeThreshold))
                    .withCircuitBreakerSleepWindowInMilliseconds(Integer.parseInt(withCircuitBreakerSleepWindowInMilliseconds)));
}

}
`
and configure it with the following configuration in the applicationContext.xml:

`

    <property name="withCircuitBreakerEnabled" value="true"></property>
    <property name="withCircuitBreakerForceClosed" value ="false"></property>
    <property name="withCircuitBreakerForceOpen" value ="false"></property>
    <property name="withCircuitBreakerErrorThresholdPercentage" value ="50"></property>
    <property name="withCircuitBreakerRequestVolumeThreshold" value ="10"></property>
    <property name="withCircuitBreakerSleepWindowInMilliseconds" value ="20000"></property>
</bean>
  <aop:config>
    <aop:aspect id="consumeServiceAspect" ref="consumeCommand">
        <aop:pointcut id="consumeServiceTarget"
                      expression="execution(* com.mobile.pay.service.impl.PayUserConsumeServiceImpl.consume(..))"/>
        <aop:around method="runCommand" pointcut-ref="consumeServiceTarget"/>
    </aop:aspect>
</aop:config>  `

and the target method is annotationed with @Transactional :
`@Override
@Transactional(propagation=Propagation.REQUIRED)
public Map consume(PayUserConsume uc,PayGoods payGoods) {
//some CUD operation

}`
when there is a SQL Exception, the hystrix works well，however， there is no rolling back. It means that the hystrix intercepts the Exception before the Spring transaction?

[jordandandan]

I add the following code
@Override @Transactional(propagation=Propagation.REQUIRED,rollbackFor=Exception.class)
then the hystrix and transaction work well.
I guess that the hystrix intercept the exception and transform this exception to another exception which the spring transaction can not roll back for it.

[mattrjacobs]

If Spring is wrapping Hystrix, then it will only get what a normal caller of Hystrix would get. In the case of a fallback, that would generally be either the normal value, or the fallback value, not an exception at all.

[jordandandan]

You mean that the hystrix will intercept the exception and it would not throw it to the spring?
I override the run method as follow:
@Override protected Object run() throws Exception { try { return pjp.proceed(); } catch (Throwable throwable) { throw (Exception) throwable; } }
It will throw the exception, however, the spring cannnot notice it. I guess the reason is the forked thread will not throw the exception to the main thread. @mattrjacobs

[yanglifan]

@jordandandan
Spring @Transactional will only rollback RuntimeException by default. SQLException is a checked Exception. That is why you add rollbackFor=Exception.class then rollback works.

[mattrjacobs]

Looks answered now. Thanks @yanglifan ! Please re-open if there's more to discuss