Docker multi-stage builds?

[laugimethods]

Do you plan to support Docker multi-stage builds?
That feature might be easier to implement if Use a Dockerfile #56 is released...

Btw, thank you indeed for your plug-in.

[marcus-drake]

Multi-stage builds is an interesting feature, not sure how many would benefit from it. I'm not using it myself which makes it harder to build and maintain, but a PR for it would be welcome 😄

[AlexBaitov]

+1

[skonto]

@marcuslonnberg is this still true? There is no support for multi-stage builds? Would that be a lot of effort? This is a very useful feature nowadays.

[tpeikert]

+1

[jguitana]

@marcuslonnberg I was able to make multi-stage builds work with the following code.

  case class CopyMultiStage(from: String, src: String, dest: String) extends DockerfileInstruction {
    override def arguments: String = s"--from=$from $src $dest"
    override def instructionName: String = "COPY"
  }

ImmutableDockerfile
  .empty
  .from(s"${image.value} AS $multistageName")
  .run(... do a bunch of stuff ...)
  .from(otherImage.value)
  .addInstruction {
   CopyMultiStage(
     multistageName,
     copySomethingFromPreviousStage,
     copySomethingToNextStage
     )
  }
  .entryPoint(...)

Is this something we can add easily to the plugin?

[marcus-drake]

@jguitana I've now clarified in the readme how to handle instructions that are not currently directly implemented by the DSL. The new method is available in version 1.9.0.
I hope that this works for your case 🙂