1 files changed, 73 insertions, 0 deletions
diff --git a/contrib/docker/src/DockerModule.scala b/contrib/docker/src/DockerModule.scala
new file mode 100644
index 00000000..bbf4d926
--- /dev/null
+++ b/contrib/docker/src/DockerModule.scala
@@ -0,0 +1,73 @@
+import mill.T
+import mill.scalalib.JavaModule
+import os.Shellable.IterableShellable
+
+import scala.collection.immutable._
+
+trait DockerModule { outer: JavaModule =>
+
+  trait DockerConfig extends mill.Module {
+    /**
+      * Tags that should be applied to the built image
+      * In the standard registry/repository:tag format
+      */
+    def tags: T[Seq[String]] = T(List(outer.artifactName()))
+    def labels: T[Map[String, String]] = Map.empty[String, String]
+    def baseImage: T[String] = "gcr.io/distroless/java:latest"
+    def pullBaseImage: T[Boolean] = T(baseImage().endsWith(":latest"))
+    private def baseImageCacheBuster: T[(Boolean, Double)] = T.input {
+      val pull = pullBaseImage()
+      if(pull) (pull, Math.random()) else (pull, 0d)
+    }
+
+    def dockerfile: T[String] = T {
+      val jarName = assembly().path.last
+      val labelRhs = labels()
+        .map { case (k, v) =>
+          val lineBrokenValue = v
+            .replace("\r\n", "\\\r\n")
+            .replace("\n", "\\\n")
+            .replace("\r", "\\\r")
+          s""""$k"="$lineBrokenValue""""
+        }
+        .mkString(" ")
+
+      val labelLine = if(labels().isEmpty) "" else s"LABEL $labelRhs"
+
+      s"""
+         |FROM ${baseImage()}
+         |$labelLine
+         |COPY $jarName /$jarName
+         |ENTRYPOINT ["java", "-jar", "/$jarName"]
+      """.stripMargin
+    }
+
+    final def build = T {
+      val dest = T.ctx().dest
+
+      val asmPath = outer.assembly().path
+      os.copy(asmPath, dest / asmPath.last)
+
+      os.write(dest / "Dockerfile", dockerfile())
+
+      val log = T.ctx().log
+
+      val tagArgs = tags().flatMap(t => List("-t", t))
+
+      val (pull, _) = baseImageCacheBuster()
+      val pullLatestBase = IterableShellable(if(pull) Some("--pull") else None)
+
+      val result = os
+        .proc("docker", "build", tagArgs, pullLatestBase, dest)
+        .call(stdout = os.Inherit, stderr = os.Inherit)
+
+      log.info(s"Docker build completed ${if(result.exitCode == 0) "successfully" else "unsuccessfully"} with ${result.exitCode}")
+      tags()
+    }
+
+    final def push() = T.command {
+      val tags = build()
+      tags.foreach(t => os.proc("docker", "push", t).call(stdout = os.Inherit, stderr = os.Inherit))
+    }
+  }
+}
+\ No newline at end of file