message interceptors

[Ladicek]

It would be useful to have a notion of "message interceptors" for cases when you want to apply some cross-cuting logic to all messages on a number of channels (one, more than one, all). I hear from @cescoffier that this was discussed in MP Reactive Messaging, but couldn't find an issue in https://github.com/eclipse/microprofile-reactive-messaging/issues We could perhaps discuss the idea here and build a prototype in SmallRye.

Based on this discussion: https://quarkusio.zulipchat.com/#narrow/stream/187030-users/topic/Use.20RequestScoped-bean.20in.20Kafka-Interceptor

[cescoffier]

That was related to eclipse/microprofile-reactive-messaging#72.

[wicksim]

Is there any progress on this one? We are still looking for a solution for our problem discussed in https://quarkusio.zulipchat.com/#narrow/stream/187030-users/topic/Use.20RequestScoped-bean.20in.20Kafka-Interceptor. A solution with a CDI-Decorator does not seem to work, maybe because of the needed @Channel-annotation. Decorator is just not used.

So I'm still searching for a solution to intercept sending/receiving of Kafka-Messages in a way that I can read some values out of a @RequestScoped CDI-bean.

[mrickly]

Would be interesting to have this feature. For outgoing messages we have our custom implementation of the Emitter. For incoming messages, we have a CDI interceptor on the @Incoming methods, but since we need access to the metadata, we need a parameter type that contains the metdata (i.e. we cannot support Record<String, Fruit> or Fruit as parameter types).

[ozangunalp]

Initial implementation by #1856, to improve if in need