[maven extension] Exception if OTLP Exporter not configured properly

[kenfinnigan]

Description
NullPointerException if OTLP Exporter endpoint is not set.

[ERROR] Internal error: java.lang.NullPointerException -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: java.lang.NullPointerException
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:120)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:957)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:289)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:193)
    at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
    at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
    at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke (Method.java:566)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:282)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:225)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:406)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:347)
Caused by: java.lang.NullPointerException
    at io.opentelemetry.maven.OpenTelemetrySdkService.getPropagators (OpenTelemetrySdkService.java:188)
    at io.opentelemetry.maven.OtelExecutionListener.sessionStarted (OtelExecutionListener.java:80)
    at io.opentelemetry.maven.ChainedExecutionListener.sessionStarted (ChainedExecutionListener.java:38)
    at org.apache.maven.lifecycle.internal.DefaultExecutionEventCatapult.fire (DefaultExecutionEventCatapult.java:61)
    at org.apache.maven.lifecycle.internal.DefaultExecutionEventCatapult.fire (DefaultExecutionEventCatapult.java:42)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:74)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:305)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:192)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:105)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:957)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:289)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:193)
    at jdk.internal.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)
    at jdk.internal.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
    at jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke (Method.java:566)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:282)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:225)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:406)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:347)
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/InternalErrorException

Steps to reproduce
Run a Maven build with mvn -Dmaven.ext.class.path={path}/opentelemetry-maven-extension-1.7.0-SNAPSHOT.jar verify

Expectation
Build runs but doesn't capture/export traces

What applicable config did you use?
Only what was on the above command line.

Relevant Environment Information
Version: 1.7.0-SNAPSHOT
OS: macOS 11.4
Compiler (if manually compiled): AdoptOpenJDK-11.0.11+9

Additional context

[cyrille-leclerc]

Problem fixed in 1.7.0-alpha

[kenfinnigan]

@trask do I mark this as closed? What's the process?

[trask]

@trask do I mark this as closed? What's the process?

👍