Docker

• Docker

  • what is it?

  • Containers

  • Pushing image to repository

    • Pushing image to docker repo

    • Pushing image to some other repository

  • other

  • Java api

  • Fabric8

  • Dockerfile

  • Volumes

  • Deploying

  • images

  • Multistage docker image build

    • Fat jars/ layering

  • Performance

  • Docker image size

  • Disadvantages or not to use

  • Links

what is it?

• https://www.docker.com/what-docker

• https://www.youtube.com/watch?v=-NzfOhSAZpA

• https://www.linkedin.com/pulse/beginner-friendly-intro-containers-vm-docker-preethi-kasireddy/

• https://www.marcobehler.com/guides/building-docker-images

Containers

• Containers

  • https://www.docker.com/what-container

• Virtual machines

• List all existing containers (running and not running).

  • docker ps -a

• List all running containers

  • docker ps

• Stop a specific container

  • docker stop [container name]

• Stop all running containers.

  • docker stop $(docker ps -a -q)

• Delete a specific container (only if stopped).

  • docker rm [container name]

• Force delete a specific container

  • docker rm -f [container name]

• Delete all containers (only if stopped).

  • docker rm $(docker ps -a -q)

• Display logs of a container.

  • docker logs [container name]

Pushing image to repository

Pushing image to docker repo

Pushing image to some other repository

other

Java api

Fabric8

• https://www.javacodegeeks.com/2019/02/docker-ise-java-application-maven-plugin.html

Dockerfile

Volumes

Deploying

• https://www.javacodegeeks.com/2018/02/docker-java-developers-deploy-docker.html

images

• build image

  • docker build -t <name of image> /{path to dockerfile}

• run image

  • docker run --name <alias you choose> -d -p 8080:8080 <name of image>

    • -p 8080:8080 : This is setting the port to be used in you app and expoing in the docker image. This has to match the port in the dockerfile

    • if the container crashes and you want to exec on to it you can add tail -f /dev/null

      • docker run --name <alias you choose> -d -p 8080:8080 <name of image> tail -f /dev/null

• Passing arguments

  • https://forums.docker.com/t/is-it-possible-to-pass-arguments-in-dockerfile/14488/3

  • https://vsupalov.com/docker-env-vars/

• remove images

  • docker system prune

  • docker rmi <image>

• Delete all existing images

  • docker image rm $(docker images -a -q)

• https://www.digitalocean.com/community/tutorials/how-to-remove-docker-images-containers-and-volumes

Multistage docker image build

• https://dzone.com/articles/multi-stage-docker-image-build-for-java-apps

Fat jars/ layering

• https://phauer.com/2019/no-fat-jar-in-docker-image/

Performance

• https://www.thedevcoach.co.uk/docker-performance-tips-and-tricks/

Docker image size

• https://semaphoreci.com/blog/2018/03/14/docker-image-size.html

Disadvantages or not to use

• https://www.freecodecamp.org/news/7-cases-when-not-to-use-docker/

  • Do Not Use Docker if You Need to Boost Speed

  • Do Not Use Docker if You Prioritize Security

  • Do Not Use Docker if You Develop a Desktop GUI Application

  • Do Not Use Docker if You Want to Light Up Development and Debugging

  • Do Not Use Docker if You Need to Use Different Operating Systems or Kernels

  • Do Not Use Docker if You Have a Lot of Valuable Data to Store

  • Do Not Use Docker if You Are Looking for The Easiest Technology to Manage

Links

• https://docs.docker.com/

• https://github.com/wsargent/docker-cheat-sheet

• https://docker-curriculum.com/

• https://www.tutorialspoint.com/docker/index.htm

• https://github.com/LeCoupa/awesome-cheatsheets/blob/master/tools/docker.sh

• https://github.com/Albertoimpl/k8s-for-the-busy/blob/master/containerizing-java/README.adoc

• https://www.freecodecamp.org/news/a-beginners-guide-to-docker-how-to-create-your-first-docker-application-cc03de9b639f/

• https://www.freecodecamp.org/news/a-practical-guide-to-containers-dfa66d37ac30/?source=rss----336d898217ee---4