Cannot re-process old Kafka messages because of Quarkus overriding the group.id

I’m running a simple integration in Camel K:

from('kafka:bitcoin-kafka-topic?brokers=my-cluster-kafka-bootstrap.kafka-demo.svc.cluster.local:9092&groupId=myowngroupid&autoOffsetReset=earliest')
    .to('log:info')

I’m using myowngroupid to reprocess old messages using a different consumer group. But when I run this integration, I notice that the Kafka group Id is always a fixed string camel-k-integration.

The reason seems to be due to this part of the code: https://github.com/apache/camel-quarkus/blob/9344d527b2979a859e3678746bb55e54fa1abcc5/extensions/kafka/runtime/src/main/java/org/apache/camel/quarkus/component/kafka/QuarkusKafkaClientFactory.java#L63-L67

Which seems correct at first glance, but unfortunately the Quarkus config unexpectedly contains wrong values at runtime:

[cescoffier]

For the record, we merged a fix in Quarkus.

[jamesnetherton]

I created a PR that should fix this https://github.com/apache/camel-quarkus/pull/2913. To my knowledge, none of the other Camel projects dependent on CQ is explicitly forcing usage of quarkus-kubernetes-service-binding, so having a check for whether the capability is present and not setting up the custom KafkaClientFactory should be good enough.

I need to do some follow up research for changing the map put to putIfAbsent. Turns out it’s a bit tricky to have this because of the defaults that the Camel component sets for various options. However, I introduced a new config option to disable the config merging if required.