Environment variables set up from build.sbt - scala

Question

I have been trying to set up environment variables directly from build.sbt file as I need to use an assembly jar name which is defined in this file. So I've been trying to output the result of defined environment variable using echo and in the context of the Scala application code sys.props.get("SPARK_APP_JAR_PATH") but the result is blank or None, respectively.
What can be wrong with the environment variable configuration?
This how I defined the env variable in build.sbt:
assemblyJarName in assembly := "spark_app_example_test.jar"
mainClass in assembly := Some("example.SparkAppExample")
test in assembly := {}
fork := true
val envVars = sys.props("SPARK_APP_JAR_PATH") = "/path/to/jar/file"

Answer 1

That's how it works for me:
lazy val dockerRepo: String = sys.props.getOrElse("DOCKER_REPO", s"bpf.docker.repo")
Or with your example:
lazy val envVars = sys.props.getOrElse("SPARK_APP_JAR_PATH", "/path/to/jar/file")
According to the documentation:
System properties can be provided either as JVM options, or as SBT arguments, in both cases as -Dprop=value. The following properties influence SBT execution.
e.g. sbt -DSPARK_APP_JAR_PATH=/path/to/jar/file
See https://www.scala-sbt.org/release/docs/Command-Line-Reference.html#Command+Line+Options