![1. sbt-assembly gives us a fat JAR
project/plugins.sbt
> sbt assembly
…
[info] Packaging out/fancy-service.jar ...
…
[success] Total time: 6 s
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.13.0")](https://image.slidesharecdn.com/shipyourscalacodeoftenandeasywithdocker-150428064453-conversion-gate01/85/Ship-your-Scala-code-often-and-easy-with-Docker-15-320.jpg)
![Let’s build an image
> sbt docker
…
[info] Packaging out/fancy-service.jar ...
…
[info] Step 0 : FROM java:8-jre
[info] ---> 028f36974b77
…
[info] Successfully built 30c376822ced
[info] Tagging image 30c376822ced with name: demo/fancy-service:0.1-SNAPSHOT
[info] Tagging image 30c376822ced with name: demo/fancy-service:latest
[success] Total time: 20 s](https://image.slidesharecdn.com/shipyourscalacodeoftenandeasywithdocker-150428064453-conversion-gate01/85/Ship-your-Scala-code-often-and-easy-with-Docker-23-320.jpg)
Ship your Scala code often and easy with Docker
- 1. Ship your Scala code often and easy with Docker Marcus Lönnberg marcus@lonnberg.nu github.com/marcuslonnberg @lonnbergm
- 2. e-bokföring
- 4. Agenda • Intro to Docker • Building Docker images with sbt • Manage Docker containers with Scala • Docker.at(SpeedLedger)
- 6. Platform Open source Client - server REST API Immutable images Container virtualization
- 9. Docker image Dockerfile Container > docker build --tag=myimage > docker run myimage
- 10. Live demo
- 11. Building and shipping Docker images Machine 1 Dockerfile + files Machine x > docker pull myimage > docker run myimage Registry > docker build --tag=myimage > docker push myimage Machine xMachine x
- 12. Building Docker images from sbt
- 13. Manually building a Scala application as a Docker image 1. Produce a fat JAR 2. Define a Dockerfile 3. Build a Docker image
- 14. 0. Current sbt build name := "fancy-service" organization := "demo" libraryDependencies ++= Seq( "com.typesafe.akka" %% "akka-actor" % "2.3.9", "io.spray" %% "spray-routing" % “1.3.3”, ... ) build.sbt
- 15. 1. sbt-assembly gives us a fat JAR project/plugins.sbt > sbt assembly … [info] Packaging out/fancy-service.jar ... … [success] Total time: 6 s addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.13.0")
- 16. 2. Define a Dockerfile FROM ubuntu RUN apt-get update RUN apt-get install -y openjdk-8-jre-headless COPY fancy-service.jar /app/fancy-service.jar WORKDIR /app ENTRYPOINT java -jar fancy-service.jar EXPOSE 8080 Dockerfile
- 17. 2. Define a Dockerfile FROM ubuntu RUN apt-get update RUN apt-get install -y openjdk-8 COPY fancy-service.jar WORKDIR /app ENTRYPOINT java -jar fancy-service.jar EXPOSE 8080 Dockerfile FROM java:8-jre WORKDIR /app EXPOSE 8080 ENTRYPOINT java -jar fancy-service.jar COPY fancy-service.jar /app/fancy-service.jar good
- 18. 3. Building a Docker image > docker build -t demo/fancy-service . Sending build context to Docker daemon Step 0 : FROM java:8-jre ---> 028f36974b77 Step 1 : WORKDIR /app ---> fb8108515091 Step 2 : EXPOSE 8080 ---> 9512be4df795 Step 3 : ENTRYPOINT java -jar fancy-service.jar ---> 839dd75f5a96 Step 4 : COPY fancy-service.jar /app/fancy-service.jar ---> 948eb875c3b1 Removing intermediate container f9eeb9406fc7 Successfully built 948eb875c3b1
- 19. sbt-docker
- 20. sbt-docker addSbtPlugin("se.marcuslonnberg" % "sbt-docker" % "1.1.0") project/plugins.sbt enablePlugins(DockerPlugin) build.sbt
- 21. Dockerfile DSL def jarFile: File def jarName: String new Dockerfile { from("java:8-jre") workDir("/app") expose(8080) entryPointRaw(s"java -jar $jarName") copy(jarFile, s"/app/$jarName") }
- 22. Putting it all together docker <<= docker.dependsOn(assembly) dockerfile in docker := { val jarFile = (assemblyOutputPath in assembly).value val jarName = name.value + ".jar" new Dockerfile { from("java:8-jre") workDir("/app") expose(8080) entryPointRaw(s"java -jar $jarName") copy(jarFile, s"/app/$jarName") } } build.sbt
- 23. Let’s build an image > sbt docker … [info] Packaging out/fancy-service.jar ... … [info] Step 0 : FROM java:8-jre [info] ---> 028f36974b77 … [info] Successfully built 30c376822ced [info] Tagging image 30c376822ced with name: demo/fancy-service:0.1-SNAPSHOT [info] Tagging image 30c376822ced with name: demo/fancy-service:latest [success] Total time: 20 s
- 24. Image names imageNames in docker := Seq( ImageName("demo/fancy-service:" + version.value), ImageName("demo/fancy-service:latest") ) build.sbt
- 25. Immutable Dockerfile def jarFile: File def jarName: String Dockerfile.empty .from("java:8-jre") .workDir("/app") .expose(8080) .entryPointRaw(s"java -jar $jarName") .copy(jarFile, s"/app/$jarName")
- 26. Build options buildOptions in docker := BuildOptions( cache = true, removeIntermediateContainers = BuildOptions.Remove.OnSuccess, pullBaseImage = BuildOptions.Pull.Always ) build.sbt
- 27. sbt-docker • Define Dockerfiles with a DSL • Dynamically name your images • Push images to a registry github.com/marcuslonnberg/sbt-docker
- 28. Manage Docker containers from Scala
- 29. REST API
- 30. REST API
- 31. scala-docker
- 32. Live coding
- 34. Build pipeline Dev machine Build server Test Production Registry git repo > git push > sbt dockerBuildAndPush > docker pull image Dev machine
- 35. Tagging Docker images with git imageNames in docker := Seq( ImageName("demo/fancy-service:" + git.gitHeadCommit.value.get), ImageName("demo/fancy-service:" + git.gitCurrentBranch.value) )
- 36. Labels with build info val labels = Map( "build.commitId" -> git.gitHeadCommit.value.get, "build.branch" -> git.gitCurrentBranch.value, "build.appName" -> name.value, "build.buildTime" -> Platform.currentTime.toString ) new Dockerfile { … label(labels) … } Docker >= 1.6
- 37. Internal sbt plugin • Adds common libraries • Generates build info • Configures logging • Adds monitoring • Sets good runtime properties • Defines a Dockerfile template
- 39. What we have learned • Order instructions in Dockerfiles for fast builds • Docker is very easy to use except for networking and file persistence • Define own base images but use official when ones exist • Building tools around Docker is easy and fun
- 40. Links • github.com/marcuslonnberg/sbt-docker • github.com/marcuslonnberg/scala-docker • github.com/sbt/sbt-assembly • github.com/sbt/sbt-native-packager