sbt-native-packager docker:publishLocal returns: Nonzero exit value: 125

Question

I'm trying to dockerize my scala application using the sbt-native-packager plugin. I've added the proper elements to build.sbt (see below).

addSbtPlugin("com.typesafe.sbt" % "sbt-native-packager" % "1.3.6")

and

enablePlugins(JavaAppPackaging)

I then run (succesfully):

sbt stage 

And then I run:

sbt docker:publishLocal

But it fails with this error:

[error] invalid argument "my-service:3.0.3-b29+2-0d2a26e3+20210402-1141" for "-t, --tag" flag: invalid reference format
[error] See 'docker build --help'.
[error] stack trace is suppressed; run 'last Docker / publishLocal' for the full output
[error] (Docker / publishLocal) Nonzero exit value: 125
[error] Total time: 18 s, completed Apr 2, 2021 11:43:32 AM

Q: What does this error mean?

This is my build.sbt:

name := """my-service"""
organization := "my.org"
scalaVersion := "2.12.4"
    
dynverVTagPrefix in ThisBuild := false
    
lazy val root = (project in file("."))
  .enablePlugins(JavaAppPackaging)
  .enablePlugins(PlayScala)
  .enablePlugins(BuildInfoPlugin)
    .settings(
      buildInfoKeys := Seq[BuildInfoKey](name, version, scalaVersion, sbtVersion),
      buildInfoPackage := "controllers"
    )
libraryDependencies += guice
libraryDependencies += jdbc
libraryDependencies += ws
libraryDependencies += "mysql" % "mysql-connector-java" % "8.0.14"
libraryDependencies += "com.typesafe.play" %% "play-slick" % "3.0.3"
libraryDependencies += "javax.xml.bind" % "jaxb-api" % "2.3.1"

libraryDependencies ++= Seq(
  "org.scalatestplus.play" %% "scalatestplus-play" % "3.1.2" % Test,
  jdbc % Test
)

Answer 1

The solution was that the build.sbt was missing the version! The version seems to be used as the docker tag!

I only needed to add the version to the top of the build.sbt and the error went away, like this:

name := """my-service"""
organization := "my.org"
scalaVersion := "2.12.4"
version      := "0.1.0-SNAPSHOT"