I took a slightly different approach. Since sbt-native-packager keeps those two files (application.conf and logback.xml) in my package distribution jar file, I really just wanted a way to overwrite (or merge) these files from /etc. I kept the two mappings above and just added the following:
src/main/templates/etc-default:
-Dmyapplication.config=/etc/${{app_name}}/application.conf
-Dlogback.configurationFile=/etc/${{app_name}}/logback.xml
Then within my code (using Typesafe Config Libraries):
lazy val baseConfig = ConfigFactory.load //defaults from src/resources
//For use in Debain packaging script. (see etc-default)
val systemConfig = Option(System.getProperty("myapplication.config")) match {
case Some(cfile) => ConfigFactory.parseFile(new File(cfile)).withFallback(baseConfig)
case None => baseConfig
}
And of course -Dlogback.configuration is a system propety used by Logback.