Presentation given during Confoo Montreal 2017

1. DOCKER AND JAVA
ANTHONY DAHANNE, CONFOO MONTRÉAL,
THURSDAY, MARCH 9TH, 2017
@anthonydahanne
http://blog.dahanne.net

2. „Anthony Dahanne, Software Engineer @ Terracotta,
a Software AG company
„Working on the Terracotta Management Console,
and its integration in Terracotta products
„And strong Docker supporter :-P , trying to
containerize as much as I can !
LET ME INTRODUCE MYSELF

3. AGENDA
•Docker fundamentals : quick recap
•Java applications in containers
• Hello world from a Java container
• SpringBoot app in a container (+ Maven + IntelliJ IDEA integrations)
• Multi container deployment
• Extras
• CI/CD on premises (Jenkins, Nexus) vs cloud based deployment
• Interacting with Docker from Java with Docker Java

4. DOCKER FUNDAMENTALS
QUICK RECAP.

5. VMS VS CONTAINERS
IT’S ALL ABOUT THE (LINUX?) KERNEL !
picture from http://www.enterprisetech.com/2014/08/18/ibm-techies-pit-docker-kvm-bare-metal/

6. DOCKER CONTAINERS / IMAGES : A PILE OF LAYERS
A DOCKER IMAGE IS A DIFF ON TOP OF ITS PARENT
picture from : https://docs.docker.com/v1.6/terms/layer/

7. Host OS
Docker daemon
Images Containers
Docker CLI
> docker run ubuntu bash
> docker ps
> docker images
> etc.
Docker Compose
> docker-compose build
> docker-compose up
> docker-compose kill
> etc.
Volumes
Kitematic
REST API
tcp (tls) / Unix socket
Host OS
Docker daemon
Ima Contai
ners
Volume

8. DOCKER VOCABULARY VS JAVA VOCABULARY
• Repository : houses grouped artifacts
• Artifact : org.ehcache:ehcache:3.1.3 (+type : jar/sources/etc.)
Group id VersionArtifact id

9. DOCKER VOCABULARY VS JAVA VOCABULARY
• Registry : hosts repositories
• Repositories : house collections of tagged images
• Image : localhost:5000/anthony/mycoolproduct:v2
DockerHub / quay.io / Registry V2
Registry location Repository name Tag

10. Host OS
Docker daemon
Images
DockerHub Registry
ubuntu
latest 12.04
anthonydahanne/terracotta
latest 4.3.1-oss
anthonydahanne/petclinic
Registry @ SoftwareAG
anthony/tmc
latest 5.0
Host OS
Docker daemon
Images
Docker CLI Docker CLI
REST API
tcp (tls) / Unix socket

11. JAVA APPLICATIONS IN CONTAINERS
FROM MAIN() TO THE CLOUD !

12. DEMO TIME !
• Hello world from a Java container
• SpringBoot app in a container (+ Maven + IntelliJ IDEA integrations)

13. n
…
PostgreSQL
Webapp with
Ehcache3 Clustered
Terracotta Server
MULTI CONTAINER DEPLOYMENT
Load Balancer + Webapp + Terracotta Server + PostgreSQL DB
LoadBalancer

14. DEMO TIME !
• Ehcache demo image design
• JHipster application with clustered caching
• Depends on Terracotta Server and a Database
• Ehcache demo cloud based deployment
• 1 PostgreSQL Database
• 1 Terracotta Server instance
• n Webapp instances
• 1 load balancer

15. EXTRAS
CI/CD, OTHER JAVA INTEGRATIONS

16. Deployment infra.
ON PREMISES CI/CD
RE USING EXISTING INFRA !
Git Repo
Jenkins
Commit & Push
Trigger mvn job
Create & Start Container
Docker
daemons
Regular
Slaves
Registry
Image build
Push image to registry
Docker
daemon
Download
Images

17. DOCKER CLOUD DEPLOYMENT
PUSH THAT CODE AROUND !
EC2 Azure GCE
DockerCloudGithub DockerHub
Commit & Push
Trigger Automated Build Trigger Redeploy / Scale
Create & Start Container

18. JENKINS DOCKER PLUGIN : ADD CONTAINER BASED SLAVES

19. INTERACTING WITH THE DOCKER DAEMON WITH DOCKER JAVA
DockerClient dockerClient = DockerClientBuilder.getInstance(dockerUrl).build();
Info info = dockerClient.infoCmd().exec();
List<Container> containers = dockerClient.listContainersCmd()
.withShowAll(false)
.exec();
CreateContainerResponse container = dockerClient.createContainerCmd("busybox")
.withCmd("touch", "/test")
.exec();
dockerClient.startContainerCmd(container.getId()).exec();
dockerClient.stopContainerCmd(container.getId()).exec();
<dependency>
<groupId>com.github.docker-java</groupId>
<artifactId>docker-java</artifactId>
<version>3.0.1</version>
</dependency>
Demo at available at : https://github.com/anthonydahanne/montrealjug_docker_java/tree/04_spring_boot_app_docker_api

20. LINKS OF INTERESTS
• Docker labs, self paced (great to learn Docker !)
https://training.docker.com/category/self-paced-online
https://github.com/docker/labs/tree/master/beginner
• Jenkins plugins
https://wiki.jenkins-ci.org/display/JENKINS/Support+Core+Plugin
https://wiki.jenkins-ci.org/display/JENKINS/Docker+build+step+plugin
https://wiki.jenkins-ci.org/display/JENKINS/CloudBees+Docker+Build+and+Publish+plugin
• DockerHub repositories
https://hub.docker.com/_/openjdk/
https://hub.docker.com/_/jenkins/
https://hub.docker.com/_/maven/
https://hub.docker.com/r/anthonydahanne/terracotta-server-oss/
• Others
https://wiki.eclipse.org/Linux_Tools_Project/Docker_Tooling/User_Guide
https://plugins.jetbrains.com/plugin/7724 use socat with Docker For Mac !
http://www.sonatype.org/nexus/2015/09/22/docker-and-nexus-3-ready-set-action/
• Docker & Java talks
The JVM and Docker. A good idea? by Christopher Batey
Docker Tips & Tricks for Java Developers, by Ray Tsang

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