[JENKINS-43950] Fix some exceptions breaking mvn clean hpi:run

[jglick]

Observed in workflow-job-plugin@master, using 2.29 parent, that mvn clean hpi:run (with no package in between, for example) would fail with

java.lang.NullPointerException
	at org.jenkinsci.maven.plugins.hpi.MavenArtifact.getActualArtifactId(MavenArtifact.java:146)
	at org.jenkinsci.maven.plugins.hpi.RunMojo.execute(RunMojo.java:333)
	at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)

Fixed that and then got another exception:

java.lang.NullPointerException
	at org.jenkinsci.maven.plugins.hpi.RunMojo.configureWebApplication(RunMojo.java:460)
	at org.jenkinsci.maven.plugins.hpi.AbstractJettyMojo.startJetty(AbstractJettyMojo.java:502)

The second fix makes it work. Perhaps there is a simpler solution.

@reviewbybees

[ghost]

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[jglick]

[ERROR] Parser Exception: META-INF/maven/site.vm
org.apache.velocity.runtime.parser.ParseException: Encountered "source" at line 1039, column 52.
Was expecting one of:
    "," ...
    ")" ...
    <WHITESPACE> ...
    
	at org.apache.velocity.runtime.parser.Parser.generateParseException(Parser.java:3679)
	at …

Not sure what that is about, checking…

[jglick]

Happens in master too, will check it separately.

[jglick]

@reviewbybees done

[KostyaSha]

What introduced this issue?

[jglick]

@KostyaSha see #64.

[oleg-nenashev]

LGTM 🐝

[jglick]

Hmm, however there is also the dependencyResolution parameter, used at the start of execute; and resolveDependencies("test") in getJenkinsWarArtifact. Yet these do not work. @stephenc any clue what is going on here?

[stephenc]

I think something is attaching artifacts to the reactor and then they get wiped by clean and the re-attach is appending to the list, not replacing... does it happen with Maven 3.2.x?

[jglick]

IIRC I was testing with 3.3.9 at the time.

[jglick]

AFAIK the change is helpful and harmless, but withdrawing from consideration until I have time to dig more deeply into why the problem is happening and to check if there is a better solution.

[jglick]

I guess I do not actually have time to dig more deeply, and this fix helps people, so 🤷‍♂️

[carlossg]

This fixes JENKINS-43950