Add Quarkus example

[ruromero]

Adding a Quarkus example. It exposes an endpoint to consume CloudEvents and periodically emits CloudEvents to this same endpoint using a REST client.

See the README for more details.

Signed-off-by: ruromero rromerom@redhat.com

[matejvasek]

I am pleasantly surprised this work also in native mode. The reason I am surprised is because I would expected the User class cause troubles due to reflection.

Some time ago I tried something similar to this, to make it work I had to use @RegisterForReflection, otherwise I got errors.

Has Quarkus team done some magic to fix that in newer versions?

[slinkydeveloper]

Sounds good but I wonder if we can strip down a little bit more the sample:

• Can we remove the dockerfiles? Or do we really need these?
• Do we need all the stuff in the pom or can we simplify it?

Remember, the goal of this sample is to show how simple is to use sdk-java + restful-ws integration inside quarkus, not how to build a full app using quarkus. I think you could even link in the readme your example, showing how to build a full app, but i want to keep this one simple 😄

Also, because you're showing the restful-ws integration, i think you should rename the sample restful-ws-quarkus

[ruromero]

Has Quarkus team done some magic to fix that in newer versions?

This is what I was expecting and actually I initially added the annotation and later remove it just to try out. So maybe something has changed indeed. I will ask around and come back to you with the proper answer.

* Can we remove the dockerfiles? Or do we really need these?

Ok, I'll take out everything which is not directly related to the application. I thought leaving everything which is generated from the Quarkus Maven Plugin would be better for users getting started with Quarkus.

* Do we need all the stuff in the pom or can we simplify it?

If a user wants to try out that the native build works as well I would keep the pom as is. Native builds are very important in Quarkus as you saw in the previous comment.

Also, because you're showing the restful-ws integration, i think you should rename the sample restful-ws-quarkus

Makes sense, I'll do it.

[slinkydeveloper]

I thought leaving everything which is generated from the Quarkus Maven Plugin would be better for users getting started with Quarkus.

That's my point, this is a getting started for sdk-java to use it in quarkus, not a getting started with quarkus, that's why I also suggest you to link to a more "proper example" of a full application, because you can then show all the features of using quarkus and integrating properly with cloudevents. This IMO must be a "start using cloudevents sdk in quarkus" and that's all.

[ruromero]

Ready for another review

[slinkydeveloper]

Thanks @ruromero for the contribution!

[slinkydeveloper]

Hey @ruromero this PR fails on master CI when tested with GraalVM, can you please check it out why? https://travis-ci.org/github/cloudevents/sdk-java/builds/724844933

[matejvasek]

@slinkydeveloper I tried this on my machine with GraalVM:

openjdk version "11.0.7" 2020-04-14
OpenJDK Runtime Environment GraalVM CE 20.1.0 (build 11.0.7+10-jvmci-20.1-b02)
OpenJDK 64-Bit Server VM GraalVM CE 20.1.0 (build 11.0.7+10-jvmci-20.1-b02, mixed mode, sharing)

and test passes.

[matejvasek]

quarkusio/quarkus#11433 might be related.

[ruromero]

I did all the builds and tests with GraalVM 2.1.0

[matejvasek]

It might be something quarkus + custom maven setting.xml as in the aforementioned issue.

[slinkydeveloper]

Maybe we need to update to latest graalvm release? Any ideas of how we could fix it?

[ruromero]

I have created this PR #230