How to use Environment Variables in build.sbt?

Question

I would like to use environment variables to pass my repo credentials when using built.sbt.

I have tried things like this but the details arent picked up.

credentials += Credentials("Some Nexus Repository Manager", "my.artifact.repo.net", System.getenv("USERNAME"), System.getenv("PASSWORD")) 

I have also tried a credentials file under ~/.sbt/ but I'm not sure how to add environment variables to that.

If I just type my username and password normally in the credentials file it works so I know that the log in details are ok.

Additional: I source the environment vars in a shell before running sbt compile.

Running

credentials += Credentials("Realm", "my.artifact.repo.net", sys.env("USERNAME"), sys.env("PASSWORD")) 

results in a forbidden url error.

I should say I'm stuck trying to resolve dependencies

UPDATE: The Following returns the correct value

eval scala.sys.env("ARTIFACTORY_USERNAME") 

But when I add this into my script

val username = scala.sys.env("ARTIFACTORY_USERNAME") val password = scala.sys.env("ARTIFACTORY_PASSWORD") credentials += Credentials("Artifactory Realm", "artifactory.link.io", username, password)  resolvers ++= Seq( "Artifactory Snapshot" at "https://artifactory.link.io/art/libs-snapshot" ) 

or

credentials += Credentials("Artifactory Realm", "my.artifact.repo.net", sys.env("ARTIFACTORY_USERNAME"), sys.env("ARTIFACTORY_PASSWORD"))    

I get a FORBIDDEN URL error which suggests that the scala part runs ok but for some reason the credentials are still incorrect. If I explicitly set the credentials in the build.sbt it works.

Answer 1

You can get env variables with the commands mentioned other responses like:

sys.env.get("USERNAME") sys.env.get("PASSWORD") 

but they return an option of type Option[String]

To turn this into string you need to either do a match or simply use

sys.env.get("USERNAME").get sys.env.get("USERNAME").getOrElse("some default value") 

if you need to set some default value. Warning! calling .get of an option that does not have value will give you a runtime error.

Answer 2

You can use anything that works in Scala in sbt, for instance:

sys.env.get("PASSWORD")