Make Optaplanner build reproducible

[lucamolteni]

See #820, but for Optaplanner

[yurloc]

Blocked by

• New release to support reproducible builds  mojohaus/jaxb2-maven-plugin#296
• extension-maven-plugin does not support reproducible builds quarkusio/quarkus#38364

[hboutemy]

@yurloc did you find any issue with jaxb2 output?

[yurloc]

@yurloc did you find any issue with jaxb2 output?

I didn't. Our manual reproducibility check according to this guide fails in the mvn artifact:check-buildplan step. But when I skip that and just run

mvn clean install 
mvn clean verify artifact:compare

no difference is detected in modules that use the jaxb2 plugin (we use the schemagen goal).

If I understand the situation correctly, in our case jaxb2-maven-plugin:3.1.0:schemagen does not make the build non-reproducible.

[yurloc]

@hboutemy I've just read your comment in 296 and I agree that we don't have an issue with the jaxb2 plugin, other than failing the check-buildplan step. In case this is an optional check, then we're OK. It's just a bit misleading to someone who's new to the reproducible builds because it's not clear how important check-buildplan is.

[hboutemy]

other than failing the check-buildplan step. In case this is an optional check

yes, artifact:check-buildplan is just a helper tool to ease discovering and fixing easy/basic issues: if you see how to improve the wording on https://maven.apache.org/guides/mini/guide-reproducible-builds.html (or anywhere else), please help

FYI, I dropped jaxb2-maven-plugin because it's not really helping currently but more creating complexity

[lucamolteni]

please help

Check this please

apache/maven-site#489

[yurloc]

Second part of the Quarkus timestamps issue:

• Timestamps in jdp files prevent reproducible extension builds quarkusio/quarkus#38420

When we upgrade to a Quarkus version that contains both fixes, we no longer need a workaround.

[lucamolteni]

Fixed in apache/incubator-kie-optaplanner@08419e4