No possibility to create function definition templates

Describe the issue
We have a dynamic amount of functions that should use the same function definition within the same application. We need to define the function definition once and reuse it from the configuration for different tenants or topics.

To Reproduce

1. Create a function definition: myfunctiondefinition
2. set spring.cloud.function.definition: myfunctiondefinition1,myfunctiondefinition2
3. map myfunctiondefinition1 and myfunctiondefinition2 to myfunctiondefintion

Spring Cloud Stream 3.2.2

The issue has been raised on stackoverflow and we gave a proposal on how to handle it from within the own code. Nevertheless the current approach of Spring Cloud Streams on how to identify function definition candidates makes the code quite ugly. A native possibility for this type of templating would be much appreciated: https://stackoverflow.com/questions/72228350/can-i-use-a-spring-cloud-stream-function-definition-for-multiple-tenants-kafka

Thanks and keep up the good work!

Start by reviewing how the spring.cloud.function.definition property identifies function definitions in Spring Cloud Stream, then read the linked Stack Overflow proposal for the tenant and topic use case. Done means a function definition can be declared once and reused as a template for multiple configured functions, with the behavior covered by relevant tests.