Fixes: https://github.com/spring-cloud/spring-functions-catalog/issues/107
When we have a composition like this:
```
spring.cloud.function.definition = fileSupplier|splitterFunction
```
Then final "function" signature is like this `Supplier<Flux<Message<List<Message<?>>>>>`.
And that is exactly what we don't expected from the splitter in the end of the composition.
While Spring Cloud Stream supports de-batching, it works for a `List` output only if function is bound by itself.
In case of composition we got just a `Supplier`.
* Rework `SplitterFunctionConfiguration` for `splitterFunction` from `Function<Message<?>, List<Message<?>>>`
to `Function<Flux<Message<?>>, Flux<Message<?>>>` signature to support every possible simple and composed bindings
in Spring Cloud Stream
* Rework `SplitterFunctionApplicationTests` for new expected `Function<Flux<Message<?>>, Flux<Message<?>>>` signature
* Rework `zip-split-rabbit-binder` sample to not use a `flattenFunction` workaround
and fully rely on whatever is new for the `splitterFunction`
* Fix `ZipSplitRabbitBinderApplicationTests` moving the `@RabbitListener` into a `@TestConfiguration`.
Apparently in a new Spring Boot version the test class is registered as a bean much later than normal application context startup.
Therefore, even if the `@RabbitListener` parsed and registered properly, the `RabbitAdmin` bean
has been already started to see our extra bean definition for the `@QueueBinding`
Changing signature for the splitterFunction to reactive types would make it working even with a Supplier composition.
Fix JDBC & MongoDB suppliers to deal with a new version of Splitter function
Fix Checkstyle violations
Use `IntegrationReactiveUtils.messageSourceToFlux()` API
The `IntegrationReactiveUtils.messageSourceToFlux()` provides convenient API to represent a `MessageSource`
as a `Flux` to poll this source.
The API has an error handling logic and delay when no data emitted by the source
* Remove `org.springframework.cloud` dependencies from the project
since we don't use `@PollableBean` anymore, which comes from the `spring-cloud-function-context`
* Simplify `JdbcSupplierConfiguration` and `MongodbSupplierConfiguration` code more: more injections to the respective bean method.
* Use `(__) ->` lambda syntax for unused argument
* Remove unused `ThreadLocalFluxSinkMessageChannel` internal class
* Update Copyrights of the classes in this change
Upgrade to Gradle `8.12`
Fixes: https://github.com/spring-cloud/spring-functions-catalog/issues/106
The `AbstractMessageSplitter messageSplitter` injection is too wide,
and if target application has its own splitter bean, it becomes as a candidate.
Since `SplitterFunctionConfiguration` expects only its own beans, rework the logic for `@Qualifier`
and `Optional` to be explicit for expected beans from the `SplitterFunctionConfiguration`.
* Add `spring-` prefix to function names
Fixes: #9
This commit renames each sub-module in the common, consumer, function
and supplier groups with a prefix of `spring-`.
* Update README.adoc links to new prefixed names
