RESTEASY-3006 Allow microprofile-client to inject Vertx engine for HTTP/2 communication

[liweinan]

resolves #8

[jamezp]

Overall I think this looks okay. I want to think about if we can get it to work without having to use the RestClientBuilderImpl directly. One thing that comes to mind is doing something like:

HttpClientOptions options = new HttpClientOptions();
options.setSsl(true);
options.setProtocolVersion(HttpVersion.HTTP_2);
options.setUseAlpn(true);

builder.setProperty("org.jboss.resteasy.http.client.engine", new VertxClientHttpEngine(Vertx.vertx(), options));

Then the RestClientBuilderImpl itself looks for the property. It requires knowledge of the ClientHttpEngine, but that seems okay as that is a public API and IMO the RestClientBuilderImpl should not be a public API.

[liweinan]

@jamezp Unfortunately RestClientBuilder doesn't have a setProperty() method and it's defined by eclipse community:

Shall I submit a request to add a method into the interface to the eclipse community? Is there any workflow to submit it?

[jamezp]

@jamezp Unfortunately RestClientBuilder doesn't have a setProperty() method and it's defined by eclipse community:

Shall I submit a request to add a method into the interface to the eclipse community? Is there any workflow to submit it?

There should be as it extends javax.ws.rs.core.Configurable. I had a typo in my example and it should be builder.property("org.jboss.resteasy.http.client.engine", new VertxClientHttpEngine(Vertx.vertx(), options));. The builder.getConfiguration().getProperty("org.jboss.resteasy.http.client.engine") could be used in the implementation to lookup the requested engine.

[liweinan]

@jamezp Thanks for the suggestion! I'll go on working on this :D

[liweinan]

@jamezp I have modified all the places you've mentioned, could you please help to do a final check? Thanks! :D

(the test error in above I checked is because of Github CI platform network problem)

After this PR is merged I'll:

• Write a blog related with HTTP/2 client support on resteasy side and resteasy-microprofile side.
• Create a similar PR to resteasy-reactive-client (to Quarkus).

[liweinan]

@jamezp I merged the PR, if there is any problem pls let me know.