In a few words: I'm trying to decide between using the default Spring for Apache Kafka stack, KafkaTemplate or the pair, ReactiveKafkaProducerTemplate and ReactiveKafkaConsumerTemplate for my Reactor based application.
Some more context:
In the company I work we're developing a high-disponibility application aiming to publish a set of requests directly to a Kafka Broker. Since this is an API centric application expecting to receive a few millions of requests per week, we decided to go with a stack based on the Project Reactor with Spring WebFlux and Kotlin.
After doing some digging I've discovered that the Spring for Apache Kafka has a simple wrapper designed around the Reactor Kafka implementation, but this wrapper lacks a lot of the functionalities present in the default KafkaTemplate mentioned before, things like: A Metrics Binder out of the box (for prometheus integration), associated factories, extensive documentation, Auto configuration, etc.
I'm trying to understand what I'm really giving up when using the default implementation in favor of the Reactive one. Am I giving up back pressure functionality? Am I sacrificing the Reactive Stack present in my application? Will this be a toll in the future? Does anyone has some experience in working with a Reactive Stack alongside a non-reactive solution?
I have, also, a few concerns regarding the DLT flow facilitated in the default implementation, things like the SeekToCurrentErrorHandler strategy