Cannot pass arguments using sbt to gatling simulation

Question

Regarding to Gatling SBT execute a specific simulation topic is there any way to pass argument to simulation?

I've been trying passing command from any CLI like:

sbt -Dx=1 -Dy=2 -Dz=3 "gatling:testOnly fooSimulation"

and:

sbt "-Dx=1 -Dy=2 -Dz=3 gatling:testOnly fooSimulation"

and all similar variations, but in result it gives just a null value.

Same thing I was trying to do in sbt shell, because I use it as well, but no success at all. Maybe my specific configuration in build.sbt is the main reason why it doesn't work. Nevertheless I do not want to pass the arguments in config file, it should be dynamic.

build.sbt

name := "Gatling"
version := "0.1"
scalaVersion := "2.12.11"

enablePlugins(GatlingPlugin)

fork := true

scalacOptions := Seq(
  "-encoding", "UTF-8", "-target:jvm-1.8", "-deprecation",
  "-feature", "-unchecked", "-language:implicitConversions", "-language:postfixOps")

libraryDependencies += "io.gatling.highcharts" % "gatling-charts-highcharts" % "3.3.1" % Test
libraryDependencies += "io.gatling" % "gatling-test-framework" % "3.3.1" % Test
libraryDependencies += "org.json4s" % "json4s-native_2.12" % "3.6.7" % Test
libraryDependencies += "org.scalatest" %% "scalatest" % "3.0.8" % Test
libraryDependencies += "com.microsoft.sqlserver" % "mssql-jdbc" % "7.2.2.jre8" % Test
libraryDependencies += "org.springframework.boot" % "spring-boot-starter" % "2.3.5.RELEASE" % Test
libraryDependencies += "com.typesafe" % "config" % "1.4.1" % Test

Test / javaOptions += "-DpropertiesFile=./src/test/resources/application.properties"

plugins.sbt

addSbtPlugin("io.gatling" % "gatling-sbt" % "3.2.0")

Example code:

class FooSimulation extends Simulation {

  before {
    println(s"x=${System.getProperty("x")}")
    println(s"y=${System.getProperty("y")}")
    println(s"z=${System.getProperty("z")}")
  }

  setUp(
    scenario("Foo")
      .exec( foo chain builder )
      .inject( foo injection )
  ).protocols( foo protocol )
}

Additionally my sbt shell is running with prefix sbt:gatling, maybe this is the reason?

Answer 1

sbt -Dx=1 -Dy=2 -Dz=3 "gatling:testOnly fooSimulation" is correct.

But the modern sbt syntax is sbt -Dx=1 -Dy=2 -Dz=3 "Gatling/testOnly fooSimulation".

If it doesn't work, you probably have a typo somewhere, or possibly your version of sbt and Gatling are way too old and your should upgrade.