Allow to exclude JAX-RS classes with annotations

[essobedo]

Description

The idea of this feature is to provide an easy way to include/exclude JAX-RS resource, provider and feature classes at build time.

So far, the only way to keep control over the JAX-RS resource, provider and feature classes that we will have in our application is to rely on a JAX-RS Application class but it is not really convenient as soon as we have a lot of classes in our project and we want to keep JAX-RS classes for different applications within the same project.

It would be nice if we could have a way to easily exclude JAX-RS classes at build time using annotations like build time conditions

Implementation ideas

The idea could be to allow to annotate JAX-RS classes with build time conditions in order to include them at build time only if the conditions are met, like in the following example:

@IfBuildProfile("app1")
public class ResourceForApp1Only {

    @GET
    @Path("sayHello")
    public String sayHello() {
        return "hello";
     }
}

[essobedo]

Here is a potential fix for it #15215

[Legion2]

Another use case for this is to provide a utility endpoint for the dev mode.

For example when working with reactive messaging, you can replace an incoming channel with a REST endpoint. The developer can then POST messages to the channel using the swagger ui, instead of locally deploying a complex messaging middleware for just passing messages into the application.

@Path("dev")
@ApplicationScoped
@IfBuildProfile("dev")
class DevQueues {

    @Inject
    lateinit var mapper: ObjectMapper

    @Inject
    @Channel("test")
    lateinit var emitter: Emitter<String>

    @POST
    @Path("queue/test")
    fun create(message: DataModel): CompletionStage<Void> {
        return emitter.send(mapper.writeValueAsString(message))
    }
}