Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Containerized Applications with Docker
Search
Laura Frank
March 26, 2015
Technology
2
160
Containerized Applications with Docker
An introduction to developing applications with Docker. Given at Ancient City Ruby 2015
Laura Frank
March 26, 2015
Tweet
Share
More Decks by Laura Frank
See All by Laura Frank
GOTO Night Chicago -- Containerizing your Dev Environment
rheinwein
1
120
Building Containerized Applications with Docker
rheinwein
0
97
Other Decks in Technology
See All in Technology
整頓のジレンマとの戦い〜Tidy First?で振り返る事業とキャリアの歩み〜/Fighting the tidiness dilemma〜Business and Career Milestones Reflected on in Tidy First?〜
bitkey
1
3.1k
LangSmith×Webhook連携で実現するプロンプトドリブンCI/CD
sergicalsix
1
160
あなたの声を届けよう! 女性エンジニア登壇の意義とアウトプット実践ガイド #wttjp / Call for Your Voice
kondoyuko
4
520
Tokyo_reInforce_2025_recap_iam_access_analyzer
hiashisan
0
150
一体いつからSRE NEXTがSREだけのカンファレンスだと錯覚していた? / When did you ever get the idea that SRE NEXT was a conference just for SREs?
vtryo
1
120
OpenHands🤲にContributeしてみた
kotauchisunsun
1
500
作曲家がボカロを使うようにPdMはAIを使え
itotaxi
0
400
Tech-Verse 2025 Global CTO Session
lycorptech_jp
PRO
0
1.2k
ビズリーチが挑む メトリクスを活用した技術的負債の解消 / dev-productivity-con2025
visional_engineering_and_design
1
1.4k
生成AI開発案件におけるClineの業務活用事例とTips
shinya337
0
190
強化されたAmazon Location Serviceによる新機能と開発者体験
dayjournal
4
280
asken AI勉強会(Android)
tadashi_sato
0
150
Featured
See All Featured
GraphQLの誤解/rethinking-graphql
sonatard
71
11k
Chrome DevTools: State of the Union 2024 - Debugging React & Beyond
addyosmani
7
730
Creating an realtime collaboration tool: Agile Flush - .NET Oxford
marcduiker
30
2.1k
How GitHub (no longer) Works
holman
314
140k
What's in a price? How to price your products and services
michaelherold
246
12k
Building Adaptive Systems
keathley
43
2.6k
Embracing the Ebb and Flow
colly
86
4.7k
The Illustrated Children's Guide to Kubernetes
chrisshort
48
50k
Documentation Writing (for coders)
carmenintech
72
4.9k
The World Runs on Bad Software
bkeepers
PRO
69
11k
Building Better People: How to give real-time feedback that sticks.
wjessup
367
19k
KATA
mclloyd
30
14k
Transcript
Containerized Ruby Applications with Docker Laura Frank rheinwein @rhein_wein
None
+
Containerization: What even is it? How do I use Docker
within my applications? How can I use Docker with Ruby? Three Questions
None
Docker may seem trendy right now… but there’s a reason
it’s popular.
Docker != containers
A tool for managing containers • Executing and running code
• Managing code Docker
First, let’s talk about containers.
• Run in a self-contained execution environment • Share the
kernel of host system • Are isolated from other containers • Have fast boot times & low overhead Containers
LXC/libcontainer/… - container format namespaces - isolation cgroups - sharing
unionfs - layering Containers
A container is a virtualization layer — sort of like
a VM — but with some fundamental differences Containers can work in conjunction with or in place of virtual machines (VMs).
hardware host OS hypervisor $ guest OS libraries web $
guest OS $ guest OS libraries DB libraries web
hardware host OS libraries web libraries DB libraries web
hardware host OS container runtime engine libraries libraries web web
DB
Containers have slightly more complexity but They reduce the amount
of time/space resources needed to run your application
None
A tool for managing containers • Executing and running code
• Managing code Docker
Engine Hub docker.com
The Docker Hub • Ideas • News • Images (Docker
Registry)
registry.hub.docker.com
Using Ruby with Docker
Installing Docker
Anything else? You need to use a lightweight VM. Pro
Tip: Boot2Docker (OSX and Windows) Installing Docker Linux? Install Docker with official packages. Kitematic (OSX)
CLI REST API docs.docker.com Interacting with Docker
None
Docker Images An image is controlled by a Dockerfile docker
build -t foo/bar . docker pull foo/bar
• Static: all files and code are contained in image
• Dynamic: link folders to actively modify code (development only) Sehr wichtig/very important/¡muy importante! Docker Images
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> EXPOSE 4567 RUN mkdir
-p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD “ruby hello_world.rb" Dockerfile
ENV KEY value Declare any environment variables that will be
passed to any RUN command. VOLUME /var/foo VOLUME [“/var/foo”, “/var/bar”] creates a mount point for volumes from host or other containers
FROM centurylink/ruby-base:2.1.2 Dockerfile No need for gemset or version management,
just use a different base image. Base images are great!
Official Ruby Images https://registry.hub.docker.com/_/ruby/ Support for 1.9.3+ docker pull ruby:2.1.X
Repository includes instructions for bootstrapping
Gems From Swipely: docker-api: for interacting with the Docker API
from your Ruby application Over 30 other gems
(Sorry.) …is kind of a pain. Debugging in a Container…
Debugging in a Container Use Pry. require ‘pry’ class Thing
def some_method binding.pry #some brilliant broken code end end
Debugging in a Container No need for a remote session*
Alternatively, use pry command: docker run centurylink/panamax-api pry
None
Application Architecture with Docker
Simply put, Docker architecture is service-oriented architecture. If a service
fails, new containers can be spun up in milliseconds.
DB Web One Service, One Container
Bind 8080:4567 Expose 3306 link One Service, One Container DB
Web
Configuration can happen in two places: The Dockerfile, by baking
config options into the service’s base image The docker run string, by specifying configuration options with various flags Configuring an Application
Bind 8080:4567 Expose 3306 One Service, One Container link DB
Web
Bind 8080:4567 The Dockerfile Link: DB Web FROM centurylink/ruby-base:2.1.2 MAINTAINER
Laura Frank <
[email protected]
> RUN mkdir -p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD ["ruby", "hello_world.rb"]
Bind 8080:4567 FROM centurylink/ruby-base:2.1.2 MAINTAINER Laura Frank <
[email protected]
> ENV APIKEY=superSeCrEt01234567abcdef!
RUN mkdir -p /usr/src/app ADD . /usr/src/app WORKDIR /usr/src/app RUN bundle install CMD ["ruby", "hello_world.rb"] The Dockerfile Link: DB Web
Bind 8080:4567 Link: DB The Docker Run String Web docker
run -p 8080:4567 -e “APIKEY=superSeCrEt01234567abcdef!” —-link db:db my-image
The Docker Run String Each container has own docker run
string Can only start one container at a time via CLI Multiple containers can run from the same image Find balance between docker run and Dockerfile
…that sounds like a lot of tedious work.
None
Application Templating Use your own images, or images from the
Docker Registry Specify config options beforehand Run applications with one or two simple commands
Standards tightly coupled with Docker docs.docker.com/compose Dump requirements into docker-compose.yml
and run with docker-compose up Docker Compose
Docker workflow tool Itself a containerized application panamax.io Uses CoreOS,
Fleet, and etcd for orchestration and service discovery
Templating language similar to docker compose Supports remote deployments panamax.io/get-panamax
--- name: Rails with PostgreSQL description: Rails with PostgreSQL images:
- category: Web Tier name: Rails source: rheinwein/rails:latest description: Rails App type: Default expose: [] ports: - host_port: '8080' container_port: '3000' links: - service: Database alias: DB_1 environment: [] volumes: []
Parting Thoughts Extract commonalities from images in order to share
them Don’t include any user- or org-specific configurations in an image or application template Boot2Docker Use an application template
Additional Resources Docker Hub: registry.hub.docker.com Documentation: docs.docker.com Boot2Docker: boot2docker.io Panamax:
panamax.io CenturyLink Labs: centurylinklabs.com
Thanks! Laura Frank rheinwein @rhein_wein