How to gracefully exit a spring cloud function definition on exception scenario?

Question

I am using spring cloud function chaining in my project like below:

spring.cloud.function.definition = func_A|func_B|func_C|func_D

The above definition will pipe the result of func_A to func_B, and from func_B to func_C and so on...

Now if I have a business logic in func_B that requires to stop the propagation to the following functions (fun_C and func_D), how to do it? I know throwing an exception in func_B will stop the propagation, but is there any graceful way other than throwing exception?

Basically I need something like this in code level:

if(true){
   proceed to `func_C` and `func_D`
}else{
  stop and return (without throwing exception)
  (or) route to a consumer function (where I will just log a message)
}

Thanks in advance:)

Answer 1

The problem is in terminology. You are using the word "chaining", hence your question about propagation and so on. . . However. . . There is no "chaining". There is "composition" and result of a composition is a single function (as if you wrote everything yourself in a single function). So effectively you are asking how can you invoke a function without producing an output? That would simply not compile. So either throw an exception or you must return something.