How to implement Retry logic in RabbitMQ? - spring-boot

Question

In my project I'm setting SimpleRetryPolicy to add custom exception and RetryOperationsInterceptor which is consuming this policy.
#Bean
public SimpleRetryPolicy rejectionRetryPolicy() {
Map<Class<? extends Throwable>, Boolean> exceptionsMap = new HashMap<Class<? extends Throwable>, Boolean>();
exceptionsMap.put(DoNotRetryException.class, false);//not retriable
exceptionsMap.put(RetryException.class, true); //retriable
return new SimpleRetryPolicy(3, exceptionsMap, true);
}
#Bean
RetryOperationsInterceptor interceptor() {
return RetryInterceptorBuilder.stateless()
.retryPolicy(rejectionRetryPolicy())
.backOffOptions(2000L, 2, 3000L)
.recoverer(
new RepublishMessageRecoverer(rabbitTemplate(), "dlExchange", "dlRoutingKey"))
.build();
}
But with these configurations retry is not working for both RetryException and DoNotRetryException, where I want RetryException to be retried finite number of time and DoNotRetryException to send to DLQ
Please help with the issue, I'm attaching repo link if in case of need.
https://github.com/aviralnimbekar/RabbitMQ/tree/main/src

Answer 1

Your GlobalErrorHandler does its logic before the retry happens and you override there an exception with the AmqpRejectAndDontRequeueException. And looks like you do there a publish to DLX. Consider to move your GlobalErrorHandler logic to a more general ErrorHandler for the factory.setErrorHandler(); instead.
See more info in docs: https://docs.spring.io/spring-amqp/reference/html/#exception-handling
UPDATE
After removing errorHandler = "globalErrorHandler" from your #RabbitListener, I got this in logs:
2022-08-03 16:02:08.093 INFO 16896 --- [nio-8080-exec-4] c.t.r.producer.RabbitMQProducer : Message sent -> retry
2022-08-03 16:02:08.095 INFO 16896 --- [ntContainer#0-1] c.t.r.consumer.RabbitMQConsumer : Retrying message...
2022-08-03 16:02:10.096 INFO 16896 --- [ntContainer#0-1] c.t.r.consumer.RabbitMQConsumer : Retrying message...
2022-08-03 16:02:13.099 INFO 16896 --- [ntContainer#0-1] c.t.r.consumer.RabbitMQConsumer : Retrying message...
2022-08-03 16:02:13.100 WARN 16896 --- [ntContainer#0-1] o.s.a.r.retry.RepublishMessageRecoverer : Republishing failed message to exchange 'dlExchange' with routing key dlRoutingKey
2022-08-03 16:02:17.736 INFO 16896 --- [nio-8080-exec-5] c.t.r.producer.RabbitMQProducer : Message sent -> 1231231
2022-08-03 16:02:17.738 INFO 16896 --- [ntContainer#0-1] c.t.r.consumer.RabbitMQConsumer : sending into dlq...
2022-08-03 16:02:17.739 WARN 16896 --- [ntContainer#0-1] o.s.a.r.retry.RepublishMessageRecoverer : Republishing failed message to exchange 'dlExchange' with routing key dlRoutingKey
Which definitely reflects your original requirements.