How to reference SBT Customizing in subprojects

Question

To some extent similar to this question , how can a user parameter be referenced in a subproject.

In build.sbt:

import sbt.Keys._ val finagleVersion = settingKey[String]("Defines the Finagle version") val defaultSettings = Defaults.coreDefaultSettings ++ Seq( finagleVersion in ThisBuild := "6.20.0", organization in ThisBuild := "my.package", scalaVersion in ThisBuild := "2.10.4", version in ThisBuild := "0.1-SNAPSHOT" ) lazy val root = project.in(file(".")).aggregate(thrift).settings( publishArtifact in (Compile, packageBin) := false, publishArtifact in (Compile, packageDoc) := false, publishArtifact in (Compile, packageSrc) := false ) lazy val thrift = project.in(file("thrift")) 

In transaction /build.sbt:

 name := "thrift" // doesn't work libraryDependencies ++= Seq( "com.twitter" %% "finagle-thriftmux" % (finagleVersion in LocalRootProject).value ) 

Answer 1

.sbt files cannot see definitions (e.g. val s) in other .sbt files, even if they are part of the same assembly.

However, all .sbt files in the assembly can see / import the contents of the project/*.scala .sbt files. So you need to declare your val finagleVersion in a .scala file:

project/CustomKeys.scala :

 import sbt._ import Keys._ object CustomKeys { val finagleVersion = settingKey[String]("Defines the Finagle version") } 

Now, in your .sbt files, just

 import CustomKeys._ 

and you are good to go.