Development of the nar-maven-plugin

The nar-maven-plugin is an Apache Maven plugin that builds NAR files; the self-contained jar-files that encapsulate NiFi functions.

The plugin defines a Maven packaging type ('nar'). Plugins that define packaging types modify the Maven build lifecycle, and must therefore include <extensions>true</extensions> when they are configured in a POM. Plugins that declare extensions cannot be resolved from the Maven reactor. The net result of all of this is that the plugin cannot be 'just another module' in the overalll NiFi Maven build. It has to be an independent build. Further, it has to be independently released. So, even though there is a nar-maven-plugin directory in the overall git repo, that directory is an independent project, not a module of the overall NiFi project.