A simple script that will try to load configurations in the following order: 1) From properly named environment variables 2) From command line paramenters 3) From the configuration file. See article http://danielasfregola.com/2015/06/01/loading-configurations-in-scala/

MyConfig.scala

import com.typesafe.config.ConfigFactory
import scala.util.Properties

class MyConfig(fileNameOption: Option[String] = None) {
    
  val config = fileNameOption.fold(
                  ifEmpty = ConfigFactory.load() )(
                  file => ConfigFactory.load(file) )

  def envOrElseConfig(name: String): String = {
    Properties.envOrElse(
      name.toUpperCase.replaceAll("""\.""", "_"),
      config.getString(name)
    )
  }
}

val myConfig = new MyConfig()
val value = myConfig.envOrElseConfig("my.secret.value")
println(s"My secret value is $value")