DockerUtil.scala

// Take a look at the snippet. This is just a sample. You might have more/less steps as part of docker compose up
object DockerUtil {
  lazy val makeDockerFile = taskKey[Seq[ImageName]]("Make a docker image for the app.")
  lazy val makeDockerComposeFile = taskKey[File]("Make docker compose file for the project in resource managed location.")
  lazy val dockerComposeUp = taskKey[File]("docker-compose up for the project")

  def relativeDockerComposePath(resPath: File) = resPath / "docker" / "bin" / "docker-compose.yml"

  def settings = Seq(
    makeDockerFile := {
      val artifact: File = (assembly in  Compile).value
      val artifactTargetPath = s"/app/${artifact.name}"

      val dockerfile = new Dockerfile {
        from("openjdk:10-jre-slim")
        add(artifact, artifactTargetPath)
        cmd("java", "-jar", artifactTargetPath)
      }
      
      val dockerImageNames = Seq(
        ImageName(s"afsalthaj/myProject:latest"),
        ImageName(s"afsalthaj/myProject:${version.value}")
      )

      DockerBuild(
        dockerfile,
        DefaultDockerfileProcessor,
        streamImages,
        BuildOptions(),
        (target in docker).value,
        sys.env.get("DOCKER").filter(_.nonEmpty).getOrElse("docker"),
        Keys.streams.value.log
      )

      dockerImageNames
    },

    makeDockerComposeFile := {
      val resourcePath = (resourceManaged in Compile).value

      val imageName: ImageName = makeDockerFile.value(0)

      val targetFile = relativeDockerComposePath(resourcePath)

      // A sample content
      val content =
        s"""
           |version: '2'
           |services:
           |  zookeeper:
           |    image: confluentinc/cp-zookeeper:5.0.0
           |    hostname: zookeeper
           |    ports:
           |      - '32181:32181'
           | ......
           
           |  kafka:
           |    image: confluentinc/cp-enterprise-kafka:5.0.0
           |    hostname: kafka
           |  .......
           |
           |  schema-registry:
           |    image: confluentinc/cp-schema-registry:5.0.0
           |
           |  ....   
           |  custom-application:
           |    image: ${imageName}
           |    hostname: my-project-app
           |    depends_on:
           |      - kafka
           |      - schema-registry
           |      - kafka-create-topics
           |    ports:
           |      - '7070:7070'
   
        """.stripMargin

      IO.write(targetFile, content)
      targetFile
    },

    dockerComposeUp := {
      val file = makeDockerComposeFile.value
        DockerComposePlugin.dockerComposeStopInstance("pwxDockerInstance", composePath.getAbsolutePath)
        DockerComposePlugin.dockerComposeRemoveContainers("pwxDockerInstance", composePath.getAbsolutePath)
      file
    },
  )

}