The Subatomic Java Maven S2I image does not support multi module Maven projects

[donovanmuller]

Multi module Maven projects expose a bug where the S2I scripts do not cater for built .jar files in child modules. I.e. when trying to build Gluon:

$ s2i build https://github.com/absa-subatomic/gluon.git absasubatomic/s2i-jdk8-maven3-subatomic subatomic-gluon
...
[INFO] Building jar: /tmp/src/nucleus/target/nucleus-0.1.0.BUILD-SNAPSHOT.jar
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO]
[INFO] Gluon .............................................. SUCCESS [  0.002 s]
[INFO] Subatomic domain implementation .................... SUCCESS [02:44 min]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 02:50 min
[INFO] Finished at: 2018-02-26T06:30:49Z
[INFO] Final Memory: 34M/223M
[INFO] ------------------------------------------------------------------------
Copying Maven artifacts from /tmp/src/target to /deployments ...
/usr/local/s2i/assemble: line 62: cd: /tmp/src/target: No such file or directory
Running: cp *.jar /deployments
cp: cannot stat '*.jar': No such file or directory
Aborting due to error code 1 for copying artifacts from /tmp/src/target to /deployments
Build failed
ERROR: An error occurred: non-zero (13) exit code from absasubatomic/s2i-jdk8-maven3-subatomic

the scripts cannot locate the Maven artifact in nucleus/target/nucleus-0.1.0.BUILD-SNAPSHOT.jar

[donovanmuller]

Turns out this is actually already supported by the base RHEL S2I Java builder image.

Also see:

• https://docs.openshift.com/online/using_images/s2i_images/java.html#s2i-images-java-deploy-applications-from-source
• https://blog.openshift.com/maven-multi-module-projects-and-openshift/

This was related to https://github.com/absa-subatomic/gluon/issues/29