Hello, we are trying to replace KSQL with Flink Stateful Functions. The ideas is the send a data stream to Flink either through Kafka or HTTP. Our system is implemented in Golang. When trying to send HTTP messages, it always fails. We think it is because the HTTP handler expects Protobuf data and we don’t have the same proto file the handler is built with. We haven’t tried Kafka yet, but looking at the Golang SDK, it seems the message will be handled the same way and then we will be stuck with the missing proto file. Could we get some help in getting the simplest example working?

I haven't really used Flink Statefun and I'm not sure how well it's maintained - so i can't say much on that. but im eager to learn since you are migrating from KSQL why you are not using Flink SQL?

Honestly, we did not think of using Flink SQL. We picked stateful functions because we liked seemingly flexibility of stateful functions, and the possibility of consolidate all logics in one language for ease of testing and maintenance.

makes sense, im just not sure how well its supported these days and how easy it will be to get help

yes, it is a bit frustrating. It looks like the latest implementation dropped JSON support completely. It is virtually impossible to talk to it through HTTP from any other language other than java with flask