I'm trying to black-box test a Spring Boot application which is using Spring Cloud Stream Kafka. The expected results (in the DB) may differ based on the message processing order. How could I reliably tell if one message was processed and I can send in the next? One important factor is that one message from the test can generate multiple events (messages) within the application.

I did the following methods:

• wait fixed amount of time: usually works, but if someone's PC is hot and throttling, it can become flaky, and to be honest this is just ugly
• create an aspect to count the method invocations, serve it through a controller, query it multiple times, send the next message when we're "settled": timing of querying matters, unreliable
• periodically check Kafka consumer lag, either from code or by querying actuator, with multiple samples: this is mixture of the above two, sometimes slower than the first but more reliable

Is there any official way of doing this?

CodePudding user response：

Configure the container to emit ListenerContainerIdleEvents.

See https://docs.spring.io/spring-kafka/docs/current/reference/html/#idle-containers