Docker for the Rubyist
1 like762 views
This document provides an overview of Docker for Ruby developers. It begins with a brief introduction to Docker, explaining how it provides portable packaging and isolated runtime environments for applications using lightweight virtualization. It then discusses how Ruby and Ruby on Rails applications can be packaged and run using Docker, including tips on base images, separating services into different containers, and using Docker for development. It also introduces Flatcar, an experimental Ruby gem for bootstrapping new Rails projects with Docker integration.
![Running Docker
Linux
[ apt-get | yum ] install docker-engine
Docker-speci鍖c distros: CoreOS, RancherOS, etc
OSX / Windows
Requires a Linux VM
boot2docker Docker Toolbox
*](https://image.slidesharecdn.com/dockerruby-150904055102-lva1-app6891/85/Docker-for-the-Rubyist-11-320.jpg)
Docker for the Rubyist
- 1. bdehamer | CenturyLinkLabs @bdehamer | @centurylinklabs Docker for the Rubyist Brian DeHamer - CenturyLink Labs
- 3. Overview Docker 101 Ruby + Docker Rails + Docker Flatcar
- 4. Docker 101
- 5. Portable packaging format and isolated runtime environment for applications Lightweight virtualization* Docker, what is it? * Not really, but it's a useful starting point
- 6. guest OS hardware $ host OS hypervisor guest OS guest OS$ $ bins/libs app 1 bins/libs app 2 bins/libs app 3
- 7. hardware host OS bins/libs app 1 bins/libs app 2 bins/libs app 3
- 8. hardware host OS Docker Engine bins/libs app 1 bins/libs app 2 bins/libs app 3
- 9. Friendly Packaging of Existing Tech namespaces - isolation of processes, networks, etc cgroups - isolation of cpu, memory, etc chroot - isolation of 鍖le system unionfs - layered 鍖le system
- 10. Docker Ecosystem Build Image Format Docker鍖le docker build Ship Docker Hub Private Registry docker push / docker pull Run Docker Engine Docker Compose docker run Docker Remote API (REST)
- 11. Running Docker Linux [ apt-get | yum ] install docker-engine Docker-speci鍖c distros: CoreOS, RancherOS, etc OSX / Windows Requires a Linux VM boot2docker Docker Toolbox *
- 13. +
- 14. Of鍖cial OS Images Image Name Size fedora:21 241 MB ubuntu:trusty 188 MB debian:jessie 125 MB alpine:3.2 5 MB busybox:latest 2 MB scratch 0 B
- 15. Of鍖cial Language Images Image Name Size rails:4.2 824 MB ruby:2.2 717 MB python:3.4 754 MB node:0.12 706 MB java:7-jdk 586 MB golang:1.4 514 MB
- 16. Smaller Ruby Images centurylink/ruby-base ~350MB Debian based Tags available for Ruby 1.9, 2.0, 2.1, 2.2 Of鍖cial repo now has "slim" images Use Alpine and roll your own! *
- 17. Drive Docker via Ruby * Docker Remote API (REST / JSON) All features exposed in Docker CLI available Client libraries available for most languages Ruby gem: docker-api (swipely/docker-api)
- 18. Docker as Packaging for Ruby Apps docker run myapp vs Ruby + OS libs + Bundler + Gems + myapp.rb
- 19. +
- 20. Docker + Rails Tips Choose your base image rails (824 MB) centurylink/ubuntu-rails (571 MB) centurylink/debian-rails (517 MB) centurylink/alpine-rails (475 MB) Roll your own
- 21. Docker + Rails Tips Embrace "One Service, One Container Separate Rails and DB containers Service discovery via container links and exposed ports (at least for the simple cases) link DBWeb EXPOSE 5432
- 22. Docker + Rails Tips Use Docker for your dev environment Alternative to RVM or rbenv? Volume mount source code into the container Use docker exec for rails, rake, bundle commands Tie it all together with Docker Compose
- 23. Flatcar Bootstrap new Rails + Docker projects Experimental gem Thin wrapper around rails new Generates docker-compose.yml for development Generates Dockerfiles for 鍖nal packaging *
- 24. bdehamer | CenturyLinkLabs @bdehamer | @centurylinklabs Thanks! Brian DeHamer - CenturyLink Labs