Immediate application shutdown after succesful start

General Discussions
1

Hi !
I have the following problem and no clue why the application behaves as described:
I created a spring boot cloud stream application with gradle or maven (same behaviour) and added a subscription to a durable queue for consuming messages send to the topic. The application starts succesful but is followed by an immediate shutdown. It looks like someone is pressing Ctrl-C to stop the application.

 :: Spring Boot ::        (v2.2.6.RELEASE)

2020-06-03 10:55:09.200  INFO 1272 --- [           main] spring.boot.Application                  : Starting Application on CE33088 with PID 1272 (C:\Users\geotte\work\dev\nas\template\spring-boot-solace\bin\main started by geotte in C:\Users\geotte\work\dev\nas\template\spring-boot-solace)
...
2020-06-03 10:55:15.432  INFO 1272 --- [           main] spring.boot.Application                  : Started Application in 7.563 seconds (JVM running for 9.291)
2020-06-03 10:55:15.450  INFO 1272 --- [extShutdownHook] c.s.j.protocol.impl.TcpClientChannel     : Channel Closed (smfclient 2)
2020-06-03 10:55:15.457  INFO 1272 --- [extShutdownHook] c.s.s.c.s.b.i.JCSMPInboundChannelAdapter : Stopping consumer flow from queue app/created/consumer.Q.app.inbox <inbound adapter ID: 73a4f0c0-f608-4218-b0e6-9fc0ffa74db9>
...

My Gradle build file looks like this:

plugins {
    id 'java'
    id 'org.springframework.boot' version '2.2.6.RELEASE'
	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
}

repositories {
    // Use jcenter for resolving dependencies.
    // You can declare any Maven/Ivy/file repository here.
    jcenter()
}

dependencies {
	implementation platform('org.springframework.cloud:spring-cloud-dependencies:Hoxton.SR3')
	implementation platform('com.solace.spring.cloud:solace-spring-cloud-bom:1.0.0')
	implementation 'com.solace.spring.cloud:spring-cloud-starter-stream-solace'
}

If i add a web starter to the application the application keeps running because of the tomcat and receives events. But this can not be the solution.
Thank you and best regards,
Gerhard

2

Just a guess: You have no permissions to subscribe - maybe something in your acl profile or client-profile.
Do you have access to broker logs ? Have a look at event.log.
If not: If you have access to cli, you can do something like

show log event lines 20
3

Ok, finally I found the “solution”:
The application must have a consumer and a supplier and both must be listed in the function paragraf in the solace stream. If I omit the supplier from the application or does not name it in the descriptor the application shuts down immediatly.
Now the working application looks like this:

@SpringBootApplication
public class Application {

	private static final Logger logger = LoggerFactory.getLogger(Application.class);

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

	@Bean
	public Consumer<String> appCreatedConsumer() {
		return String -> {
			System.out.println("String created: " + String);
		};
	}

	@Bean
	public Supplier<String> appCreatedSupplier() {
		return () -> new String("Test");
	}
}

and my application.xml looks like this:

spring:
  cloud:
    stream:
      function:
        definition: appCreatedConsumer;appCreatedSupplier
      bindings:
        appCreatedConsumer-in-0:
          group: Q.app.inbox
          destination: app/created/consumer
solace:
  java:
    host: 'tcp://192.168.99.100:55555'
    msgVpn: default
    clientUsername: admin
    clientPassword: admin
logging:
  level:
    root: info
    org:
      springframework: info

BR Gerhard

4

Hi @gerhardo,
What you’ve found is indeed a bug that we’re already working on a fix for and it will be fixed in the next release of the Solace Spring Cloud Stream binder. Both solutions that you’ve found will work in the meantime (adding a web starter or having a supplier as part for your microservice) but once the next release is available those workarounds will no longer be necessary.
-Marc

5

Actually, looks like the fix has already been merged into the master branch if you want to try it out prior to the next release: SOL-33222: Add keep-alive for SCSB consumers by Nephery · Pull Request #5 · SolaceProducts/solace-spring-cloud · GitHub

6

And a release with this fix has been cut! It should be up in maven central sometime tomorrow.
In the meantime you can find it here: Release v1.0.1 · SolaceProducts/solace-spring-cloud · GitHub
-Marc

7

Hi @marc
the new version 1.0.1 works as expected without the above workarounds. Thx.
BR Gerhard

8

Excellent, thanks for letting us know!