Add a parameter to be able to skip build native for pom type modules, leave it as false per default for backward compat

[olamy]

When using in a multi module Apache Maven build, the plugin can cause some issues for pom type project.
Such

[ERROR] Failed to execute goal org.graalvm.buildtools:native-maven-plugin:0.10.1:compile-no-fork (build-native) on project jetty-project: Image classpath is empty. Check if your classpath configuration is correct. -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.graalvm.buildtools:native-maven-plugin:0.10.1:compile-no-fork (build-native) on project jetty-project: Image classpath is empty. Check if your classpath configuration is correct.
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2 (MojoExecutor.java:333)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute (MojoExecutor.java:316)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:174)
    at org.apache.maven.lifecycle.internal.MojoExecutor.access$000 (MojoExecutor.java:75)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run (MojoExecutor.java:162)
    at org.apache.maven.buildcache.BuildCacheMojosExecutionStrategy.execute (BuildCacheMojosExecutionStrategy.java:145)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)
Caused by: org.apache.maven.plugin.MojoExecutionException: Image classpath is empty. Check if your classpath configuration is correct.
    at org.graalvm.buildtools.maven.AbstractNativeImageMojo.getClasspath (AbstractNativeImageMojo.java:394)
    at org.graalvm.buildtools.maven.AbstractNativeImageMojo.getBuildArgs (AbstractNativeImageMojo.java:192)
    at org.graalvm.buildtools.maven.AbstractNativeImageMojo.buildImage (AbstractNativeImageMojo.java:408)
    at org.graalvm.buildtools.maven.NativeCompileNoForkMojo.execute (NativeCompileNoForkMojo.java:96)

See some details here jetty/jetty.project#11683

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[olamy]

no idea what to do to sign the OCA....
I have an account with the email used to sign this commit.
I can connect to my oracle but now when I want to sign the OCA, I get this

Please contact but there is no link provided.

[fniephaus]

Hi @olamy, thanks for the PR. Maybe @alina-yur can help us find out what's going on with the OCA portal. In the meantime, could you maybe extend the description of the PR a bit and make it clear why this is needed and what problem this solves? Thank you! :)

[alina-yur]

hi @olamy! Thank you for reporting, I passed your message to the OCA team. In the meantime, can you please try again (and ideally from a different browser), maybe it was a one-time glitch?

[olamy]

@alina-yur @fniephaus all good. I tried again and it works. Thanks

[oracle-contributor-agreement]

Thank you for signing the OCA.

[alina-yur]

@olamy your OCA is now approved. happy contributing :)

[alvarosanchez]

Why do you need yet another skip parameter? Is skipNativeBuild not enough?

[joakime]

Why do you need yet another skip parameter? Is skipNativeBuild not enough?

Using that in a sub-module would also make the sub-sub-modules skip native, which is not what we want.
Skipping by packaging type is more appropriate with maven than a global skip option like skipNativeBuild.

Btw, just so you know, @olamy is a committer on the Apache Maven project itself, and is involved in countless maven plugin projects around the maven ecosystem. I trust his experience when it comes to proper maven plugin behavior and maintainability of both the maven plugin and the projects that use the maven plugin.

[alvarosanchez]

Using that in a sub-module would also make the sub-sub-modules skip native, which is not what we want.
Skipping by packaging type is more appropriate with maven than a global skip option like skipNativeBuild.

Right, in that case I think the mojo should just simply skip execution for pom projects, without needing an extra parameter.

@olamy I understand your intention was to not introduce breaking changes, which I appreciate, but we can probably regard this issue as a bug, in which case it's fine to do the change I proposed.

Btw, just so you know, @olamy is a committer on the Apache Maven project itself, and is involved in countless maven plugin projects around the maven ecosystem. I trust his experience when it comes to proper maven plugin behavior and maintainability of both the maven plugin and the projects that use the maven plugin.

Thanks for the heads-up. I didn't mean to question his skills at all. Mine was a pure question that, in retrospect, could have been written differently. Sorry if it sounded too harsh, not my intention.

[joakime]

Using that in a sub-module would also make the sub-sub-modules skip native, which is not what we want.
Skipping by packaging type is more appropriate with maven than a global skip option like skipNativeBuild.

Right, in that case I think the mojo should just simply skip execution for pom projects, without needing an extra parameter.

There are many maven plugins that simply hardcode skipping of a project if it has no source, the easiest way is to skip pom packaging projects, others take a holistic approach and ask the Project if any sources have been attached (eg: extracted from another dependency via the maven-dependency-plugin and then attached as source for compilation into non-default artifacts,, even though the project is pom packaging).

This second approach also helps with nonstandard project packaging types (eg: bundle, resource, or any of a hundred other packaging types seen in the wild)

[olamy]

@alvarosanchez it looks @joakime explained perfectly why I choose this way of skipping :)

[fniephaus]

Thanks a lot for contributing and making clear why this is the right approach! :)