Spring Cloud Stream GCP How to do Re-queue Failed Messages

Question

According to the docs here the currently supported binders (Rabbit and Kafka) rely on RetryTemplate. And for the GCP?

Detail of my project

Spring Boot Version 2.1.3.RELEASE

Dependency pom.xml

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-gcp-starter-pubsub</artifactId>
    <version>1.1.0.RELEASE</version>
</dependency>
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-gcp-pubsub-stream-binder</artifactId>
    <version>1.1.0.RELEASE</version>
</dependency>

application.properties

spring.cloud.stream.bindings.input.destination=inputtopic
spring.cloud.stream.bindings.output.destination=outputtopic

spring.cloud.gcp.project-id=testinggcp
spring.cloud.gcp.credentials.location=file:C:/Users/my_gcp_credentials.json

RestController

@EnableBinding({Source.class,Sink.class})
@RestController
public class SourceExample {

    @Autowired
    private Source source;


    @GetMapping("/newMessage")
    public UserMessage sendMessage(@RequestParam("messageBody") String messageBody,
                                   @RequestParam("username") String username) {
        UserMessage userMessage = new UserMessage(messageBody, username, LocalDateTime.now());

        this.source.output().send(new GenericMessage<>(userMessage));
        return userMessage;
    }


    @StreamListener(target = Sink.INPUT)
    public void handle(UserMessage userMessage) throws IOException {
        System.out.println(userMessage);
    }


}

score 1 · Answer 1 · answered Mar 05 '19 at 15:08

1

No, Spring Cloud GCP Pub/Sub Binder doesn't provide any retry hooks.

It is easy to use a RequestHandlerRetryAdvice on the @ServiceActivator instead of @StreamListener. So, all your failures in the POJO method are going to be retried according your configuration. The RequestHandlerRetryAdvice has a RecoveryCallback options which could be just simple ErrorMessageSendingRecoverer where you can configure some error processing and send wrong message to some Dead Letter Topic on GCP Pub/Sub.

See more info in the Reference Manual: https://docs.spring.io/spring-integration/docs/current/reference/html/#retry-advice

And a bit bellow about Advising Endpoints Using Annotations.

answered Mar 05 '19 at 15:08

Artem Bilan

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I'm really confused the ServiceActivator doesn't work. AFAIK GCP has pubSubAcknowledgementExecutor if exception thrown it automatically recall handle function (Sink.INPUT). That mean it is not necessary for the implementation of Re-queue Failed Messages? – Panup Pong Mar 06 '19 at 04:38
1

Well, in that case I think so. The ack is automatic if message has been delivered to the listener. – Artem Bilan Mar 06 '19 at 20:09
And how to retry a message when producer throw exception at this line this.source.output() – Panup Pong Mar 07 '19 at 07:07

Spring Cloud Stream GCP How to do Re-queue Failed Messages

1 Answers1