Docker+java

Docker+java

• 1.
  Docker + Java ElekMárton @anzix 2015 March DPC Consulting
• 2.
  Docker+Java
• 3.
  What is docker ●Lightweight virtualization – Container ● Repository of virtual images – 100 official image – ~45000 public images ● Versioning support – To upgrade a container ● Only for linux – Just a filesystem, the kernel of the host system is used – Windows out of scope ● Similar to – BSD jails, Linux LXC, Solaris zones
• 4.
  Docker run
• 5.
  Docker run
• 6.
  Docker run
• 7.
  Two main usecase Start a predefined container docker run jenkins Start a command in a well defined env docker run ubuntu uname -a docker run ubuntu bash
• 8.
  Volumes ● Every containeris a one time container. – All of the files will be deleted together with the container ● What about persisted data? – Solution: volumes docker run -v /root/jenkins:/var/jenkins_home jenkins
• 9.
  ● How toaccess? – By default docker containers use internal unique IP – An additional process forwards ports ● Port forwards should be defined docker run -v /root/jenkins:/var/jenkins_home -p 4567:8080 jenkins Port forward
• 10.
  Create a dockercontainer ● Snapshot an existing container – Easy but non reproducible – docker commit ● Create step-by-step from an existing container – docker build . FROM java:8 ADD build/version /app/version WORKDIR /app CMD ["bin/start.sh"]
• 11.
  ● Usually oneprocess “In almost all cases, you should only run a single process in a single container. Decoupling applications into multiple containers makes it much easier to scale horizontally and reuse containers. If that service depends on another service, make use of container linking.” Docker best practices What is inside a container
• 12.
  Docker ps
• 13.
  Upload to arepository ● docker push/pull ● Very similar to the git concept – Versions – Tagging docker images docker tag 8dbd9e392a dpc.hu:5000/backend docker push dpc.hu:5000/ubuntu Repository servers: ● docker ● artifactory
• 14.
  Docker definition “Docker isan open platform for developers and sysadmins to build, ship, and run distributed applications. Consisting of Docker Engine, a portable, ● lightweight runtime and ● packaging tool, and ● Docker Hub, a cloud service for sharing applications and automating workflows”
• 15.
  Docker definition “… Dockerenables apps to be quickly assembled from components ● and eliminates the friction between ● development, QA, and production environments.” “As a result, IT can ship faster and run the same app, unchanged, on laptops, data center VMs, and any cloud.”
• 16.
  What is missing ●How to create an alias for a complex command line – Docker compose (was fig) – Crane ● How to manage multiple machines all together/schedule containers – Kubernetes, OpenShift ● Hande logical group of containers together – Kubernetes, OpenShift
• 17.
  Docker is ecosystem ●ContainerOS – CoreOS, Project Atomic, Boot2Docker ● Open source PaaS – Flynn, Dokuu, Deis ● Scheduler/Orchestration/Management – Kubernetes, Crane, Docker Compose(fig) ● Continuous Integration – Jennkins plugins, … See also https://www.mindmeister.com/389671722/docker-ecosystem
• 18.
  (Without) Docker compose dockerrun --name mysqldb -e MYSQL_USER=mysql -e MYSQL_PASSWORD=mysql -e MYSQL_DATABASE=sample -e MYSQL_ROOT_PASSWORD=supersecret -d mysql docker run --name mywildfly --link mysqldb:db -p 8080:8080 -d arungupta/wildfly-mysql-javaee7
• 19.
  Docker compose mysqldb: image: mysql:latest environment: MYSQL_DATABASE:sample MYSQL_USER: mysql MYSQL_PASSWORD: mysql MYSQL_ROOT_PASSWORD: supersecret mywildfly: image: arungupta/wildfly-mysql-javaee7 links: - mysqldb:db ports: - 8080:8080
• 20.
  Use it fromWindows/OSX/... ● Boot2docker – Minimal virtual container (Virtualbox) – Tools to run containers in the Virtualbox ● Docker Machine installer – Windows/Linux/OSX
• 21.
  Who uses it? ●All of the big players: ● Amazon Beanstalk – Dedicated container based hosting ● Google Cloud Platform – Containers on Google Cloud Platform powered by kubernetes ● RedHat OpenShift v3 – The new version is based on kubernetes/docker ● HP – Operations Orchestration And others...
• 22.
  Docker+Java
• 23.
  Example standalone app Dockerfile FROMjava:8 WORKDIR /myapp CMD ["bin/myproj"] COPY build/install/myproj /myapp mvn install/gradle package docker build . //upload to the repository with docker push docker pull dpc.hu:5000/backend docker run dpc.hu:5000/backend
• 24.
  Example J2EE application FROMjboss/wildfly RUN add-user.sh admin Admin#70365 --silent CMD ["/opt/jboss/wildfly/bin/standalone.sh", "-b", "0.0.0.0", "-bmanagement", "0.0.0.0"] COPY target/helloworld.war /opt/jboss/wildfly/standalone/deployments/
• 25.
  Recipes ● Arun Gupta: 9Docker recipes for Java EE Applications – Use Docker Machine – Link local mysql and wildfly together – Link remote containers – Deploy Java EE Application from Eclipse
• 26.
  Maven/SBT/Gradle docker plugin
• 27.
  Artifactory
• 28.
  Continuous Deployment See: Deliverypipline and zero downtime
• 29.
  Arquilian Cube (1.0.0Alpha4) “With this extension you can start a Docker container with a server installed, deploy the required deployable file within it and execute Arquillian tests. The key point here is that if Docker is used as deployable platform in production, your tests are executed in a the same container as it will be in production, so your tests are even more real than before. But it also lets you start a container with every required service like database, mail server, … and instead of stubbing or using fake objects your tests can use real servers.” https://github.com/arquillian/arquillian-cube
• 30.
  Summary ● Container technologyis the present – lightweight virtualization – packaging – repository ● Reusable components – Continuous delivery – Use exactly the same environment – limit resources – Easy to create test containers ● Growing ecosystem – Supported solutions from the biggest vendors to the smallest startup