Using @Transactional on a method annotated with @Incoming should add @Blocking if not present

[cescoffier]

Description

When a method annotated with @Incoming is also annotated with @Transactional, it should automatically add @Blocking is no blocking annotations (from SmallRye common and Reactive Messaging) are used.

Implementation ideas

1. Detect that configuration
2. Add the annotation
3. Implement tests
4. Document

[quarkus-bot]

/cc @michalszynkiewicz, @ozangunalp, @phillip-kruger

[geoand]

Didn't @stuartwdouglas have something like this as well?

[stuartwdouglas]

It was specific to RESTEasy Reactive

[geoand]

Ah, OK

[mkouba]

It was specific to RESTEasy Reactive

Maybe this should be implemented in the quarkus-narayana-jta instead? It would not hurt to add @Blocking on every method annotated with @Transactional, or?

[cescoffier]

+1 to @mkouba proposal. It would cover most cases.

[stuartwdouglas]

How would we actually implement that though, as @Blocking is processed by lots of different extensions.

[cescoffier]

That is a good point. Even if it adds the @Blocking annotation it would need to update the index before the other extensions look for the beans. I think, for now, we would need to do it in each individual extension.

[mkouba]

How would we actually implement that though, as @Blocking is processed by lots of different extensions.

All those extensions can leverage the ArC transformers API, i.e. instead of looking at the index consumer the io.quarkus.arc.deployment.TransformedAnnotationsBuildItem and then analyze the result of TransformedAnnotationsBuildItem.getAnnotations(AnnotationTarget).

CC @cescoffier