in src/main/java/org/apache/nifi/extension/definition/extraction/ExtensionClassLoaderFactory.java [147:158]
private Set<Artifact> getNarDependencies(final Artifact narArtifact) throws MojoExecutionException, ProjectBuildingException {
final ProjectBuildingRequest narRequest = createProjectBuildingRequest();
final ProjectBuildingResult narResult = projectBuilder.build(narArtifact, narRequest);
final Set<Artifact> narDependencies = gatherArtifacts(narResult.getProject(), TreeSet::new);
narDependencies.remove(narArtifact);
narDependencies.remove(project.getArtifact());
getLog().debug("Found NAR dependency of " + narArtifact + ", which resolved to the following artifacts: " + narDependencies);
return narDependencies;
}