Add docker packaging using directives

modules/build/src/test/scala/scala/build/tests/PackagingUsingDirectiveTests.scala

@@ -51,4 +51,24 @@ class PackagingUsingDirectiveTests extends munit.FunSuite {
     }
   }
 
+  test("docker options") {
+    val inputs = TestInputs(
+      os.rel / "p.sc" ->
+        """//> using packaging.dockerFrom "openjdk:11"
+          |//> using packaging.dockerImageTag "1.0.0"
+          |//> using packaging.dockerImageRegistry "virtuslab"
+          |//> using packaging.dockerImageRepository "scala-cli"
+          |
+          |def foo() = println("hello foo")
+          |""".stripMargin
+    )
+    inputs.withLoadedBuild(buildOptions, buildThreads, bloopConfig) { (_, _, maybeBuild) =>
+      val dockerOpt = maybeBuild.options.notForBloopOptions.packageOptions.dockerOptions
+      expect(dockerOpt.from == Some("openjdk:11"))
+      expect(dockerOpt.imageTag == Some("1.0.0"))
+      expect(dockerOpt.imageRegistry == Some("virtuslab"))
+      expect(dockerOpt.imageRepository == Some("scala-cli"))
+    }
+  }
+
 }

modules/directives/src/main/scala/scala/build/preprocessing/directives/Packaging.scala

@@ -11,6 +11,7 @@ import scala.build.errors.{
   MalformedInputError,
   ModuleFormatError
 }
+import scala.build.options.packaging.DockerOptions
 import scala.build.options.{
   BuildOptions,
   JavaOpt,
@@ -27,10 +28,15 @@ import scala.cli.commands.SpecificationLevel
 @DirectiveExamples("//> using packaging.packageType \"assembly\"")
 @DirectiveExamples("//> using packaging.output \"foo\"")
 @DirectiveExamples("//> using packaging.provided \"org.apache.spark::spark-sql\"")
+@DirectiveExamples("//> using packaging.dockerFrom \"openjdk:11\"")
 @DirectiveUsage(
   """using packaging.packageType [package type]
     |using packaging.output [destination path]
     |using packaging.provided [module]
+    |using packaging.dockerFrom [base docker image]
+    |using packaging.dockerImageTag [image tag]
+    |using packaging.dockerImageRegistry [image registry]
+    |using packaging.dockerImageRepository [image repository]
     |""".stripMargin,
   """`//> using packaging.packageType `"package type"
     |
@@ -44,7 +50,11 @@ import scala.cli.commands.SpecificationLevel
 final case class Packaging(
   packageType: Option[Positioned[String]] = None,
   output: Option[String] = None,
-  provided: List[Positioned[String]] = Nil
+  provided: List[Positioned[String]] = Nil,
+  dockerFrom: Option[String] = None,
+  dockerImageTag: Option[String] = None,
+  dockerImageRegistry: Option[String] = None,
+  dockerImageRepository: Option[String] = None
 ) extends HasBuildOptions {
   // format: on
   def buildOptions: Either[BuildException, BuildOptions] = either {
@@ -90,7 +100,13 @@ final case class Packaging(
         packageOptions = PackageOptions(
           packageTypeOpt = packageTypeOpt,
           output = output0.map(_.toString),
-          provided = provided0
+          provided = provided0,
+          dockerOptions = DockerOptions(
+            from = dockerFrom,
+            imageRegistry = dockerImageRegistry,
+            imageRepository = dockerImageRepository,
+            imageTag = dockerImageTag
+          )
         )
       )
     )

website/docs/commands/package.md

@@ -456,3 +456,38 @@ This using directive makes it possible to define the destination path of the pac
 ```
 
 The using directive above makes it possible to create a package named `foo` inside the current directory.
+
+### Docker
+
+#### packaging.dockerFrom
+
+The using directive allows you to define the base Docker image that is used to run your application.
+
+```scala compile
+//> using packaging.dockerFrom "openjdk:11"
+```
+
+#### packaging.dockerFrom
+
+The using directive allows you to define the generated Docker image tag.
+
+```scala compile
+//> using packaging.dockerImageTag "1.0.0"
+```
+
+#### packaging.dockerImageRegistry
+
+The using directive allows you to define the image registry.
+
+```scala compile
+//> using packaging.dockerImageRegistry "virtuslab"
+```
+
+#### packaging.dockerImageRegistry
+
+The using directive allows you to define the image repository.
+
+```scala compile
+//> using packaging.dockerImageRepository "scala-cli"
+```
+

website/docs/reference/directives.md

@@ -146,6 +146,8 @@ Set parameters for packaging
 
 `//> using packaging.provided "org.apache.spark::spark-sql"`
 
+`//> using packaging.dockerFrom "openjdk:11"`
+
 ### Platform
 
 Set the default platform to Scala.js or Scala Native