Dockerizing Ruby Applications - The Best Practices

Dockerizing Ruby Applications - The Best Practices

• 1.
  Dockerizing Ruby Applications- TheBest Practices Lauri Nevala, Co-Founder and Software Engineer
• 2.
  Kontena briefly
• 3.
  © 2015 Kontena,Inc. What is Kontena? Open Source container platform built to maximize developer happiness. Works on any cloud, easy to setup, simple to use.
• 4.
  Quick Facts 650+GITHUB STARGAZERS >100kNUMBEROF INSTALLS FEATURED IN
• 5.
  The Container Platform
• 6.
  All Batteries Included! Built-InImage Registry Sometimes projects can not use publicly hosted container image registries like DockerHub. Kontena comes with built-in container image registry providing private and secure solution. Built-In VPN Access All containers are run inside a virtual private network by default. Nothing is exposed to Internet unless explicitly defined. With Kontena’s built-in VPN access developers can securely access those resources. Built-In Load Balancer Kontena comes with built-in load balancer. Based on Haproxy. It features fully automatic, zero-downtime operation due to deep integration with Kontena’s service discovery and orchestration technology. Aggregated Stats & Logs Kontena provides real-time log and statistics streams containers. The streams may be grouped and aggregated to produce service level streams. This allows easy viewing of logs and statistics for your application CPU, memory, disk and network usage. User Management with Audit Trail All events and actions performed through Kontena CLI or APIs are logged into audit trail. Combined with users and access control, the audit trail support makes Kontena a reliable and secure solution for any enterprise deployments. Built-In Secrets Management When your application requires access to APIs or databases, you'll often need to use secrets such as passwords and access tokens for authenticating the access. Kontena Vault is a secure key/value storage that can be used to manage secrets in Kontena.
• 7.
  “Includes all thatsh*it you don’t need to implement by yourself”
• 9.
  Dockerizing Ruby Application
• 10.
  Containers vs. VMs ©2015 Kontena, Inc. INFRA HOST OS APP INFRA HOST OS APP INFRA HOST OS APP INFRA HOST OS HYPERVISOR GUEST OS GUEST OS GUEST OS APP APP APP INFRA HOST OS CONTAINER ENGINE APP APP APP Legacy Virtualization Containerization Year 2014 
• 11.
  Docker Core Concepts •Dockerfile • Describes a Docker image • Docker image • “Compiled” version of the Dockerfile • Docker container • Running instance of the Docker image © 2015 Kontena, Inc.
• 12.
  Docker Image • Packsup the application and environment required by the application to run • Consist of image layers • Extends a base image © 2015 Kontena, Inc.
• 13.
  Ruby Base ImageStrategies • Official Ruby images • ruby:version • defacto image, has a large number of extremely common Debian packages • ruby:onbuild • really useful for "getting off the ground running”. • it's not recommended for long-term usage within a project due to the lack of control over when the ONBUILD triggers fire • ruby:slim • contains the minimal packages needed to run ruby • ruby:alpine • based on Alpine Linux. The main caveat to note is that it does use musl libc instead of glibc and friends, so certain software might run into issues depending on the depth of their libc requirements • Build your own Ruby image • Include only those libraries that are needed for your app © 2015 Kontena, Inc.
• 14.
  © 2015 Kontena,Inc. Sometimes size does matter
• 15.
  © 2015 Kontena,Inc. Ruby:2.3.1 729 MiB Ruby:2.3.1- slim 283 MiB Ruby:2.3.1- alpine 125 MiB Sizes of the Official Ruby Images
• 16.
  Docker Containers –Best practices • Run one process per container • Twelve-Factor App FTW! • Store config in the environment • Treat backing services as attached resources • Export services via port binding • Treat logs as event streams • Etc. • Don’t rely on IP addresses © 2015 Kontena, Inc.
• 17.
  Example
• 18.
  Dockerfile FROM ruby:2.3.1-alpine ADD Gemfile/app/ ADD Gemfile.lock /app/ RUN apk --update add --virtual build-dependencies ruby-dev build-base && gem install bundler --no-ri --no-rdoc && cd /app ; bundle install --without development test && apk del build-dependencies ADD . /app RUN chown -R nobody:nogroup /app USER nobody ENV RACK_ENV production EXPOSE 9292 WORKDIR /app
• 19.
  Sending build contextto Docker daemon 29.7 kB Step 1 : FROM ruby:2.3.1-alpine ---> adae74697505 Step 2 : ADD Gemfile /app/ ---> 81f926a9e4d6 Removing intermediate container 1000f93a8025 Step 3 : ADD Gemfile.lock /app/ ---> ed3e4a1dfe0e Removing intermediate container 5920c0c209e6 Step 4 : RUN apk --update add --virtual build-dependencies ruby-dev build-base && gem install bundler --no-ri --no-rdoc && cd /app ; bundle install - -without development test && apk del build-dependencies ---> Running in 09029fc13d73 fetch http://dl-cdn.alpinelinux.org/alpine/v3.3/main/x86_64/APKINDEX.tar.gz fetch http://dl-cdn.alpinelinux.org/alpine/v3.3/community/x86_64/APKINDEX.tar.gz (1/23) Installing gmp (6.1.0-r0) (2/23) Installing libgcc (5.3.0-r0) (3/23) Installing libstdc++ (5.3.0-r0) (4/23) Installing libgmpxx (6.1.0-r0) (5/23) Installing gmp-dev (6.1.0-r0) (6/23) Installing libedit (20150325.3.1-r3) (7/23) Installing ruby-libs (2.2.4-r0) (8/23) Installing ruby-dev (2.2.4-r0) (9/23) Installing binutils-libs (2.25.1-r0) (10/23) Installing binutils (2.25.1-r0) (11/23) Installing isl (0.14.1-r0) (12/23) Installing libgomp (5.3.0-r0) (13/23) Installing libatomic (5.3.0-r0) (14/23) Installing mpfr3 (3.1.2-r0) (15/23) Installing mpc1 (1.0.3-r0) (16/23) Installing gcc (5.3.0-r0) (17/23) Installing make (4.1-r0) [email protected] ~/helsinki-ruby- brigade/todo$ docker build -t kontena/todo-example:latest .
• 20.
  © 2015 Kontena,Inc. (18/23) Installing musl-dev (1.1.12-r5) (19/23) Installing libc-dev (0.7-r0) (20/23) Installing fortify-headers (0.7-r0) (21/23) Installing g++ (5.3.0-r0) (22/23) Installing build-base (0.4-r1) (23/23) Installing build-dependencies (0) Executing busybox-1.24.1-r7.trigger OK: 192 MiB in 55 packages Successfully installed bundler-1.12.5 1 gem installed Fetching gem metadata from https://rubygems.org/ Fetching version metadata from https://rubygems.org/ Installing i18n 0.7.0 Using json 1.8.3 Installing minitest 5.9.0 Installing thread_safe 0.3.5 Installing builder 3.2.2 Installing bson 4.1.1 with native extensions Installing origin 2.2.0 Installing puma 3.4.0 with native extensions Installing rack 1.5.2 Installing tilt 1.4.1 Using bundler 1.12.5 Installing tzinfo 1.2.2 Installing mongo 2.2.5 Installing rack-protection 1.5.3 Installing activesupport 4.2.6 Installing sinatra 1.4.5 Installing activemodel 4.2.6 Installing mongoid 5.1.3 Bundle complete! 3 Gemfile dependencies, 18 gems now installed. Gems in the groups development and test were not installed.
• 21.
  © 2015 Kontena,Inc. Bundled gems are installed into /usr/local/bundle. (1/23) Purging build-dependencies (0) (2/23) Purging ruby-dev (2.2.4-r0) (3/23) Purging gmp-dev (6.1.0-r0) (4/23) Purging libgmpxx (6.1.0-r0) (5/23) Purging ruby-libs (2.2.4-r0) (6/23) Purging build-base (0.4-r1) (7/23) Purging make (4.1-r0) (8/23) Purging fortify-headers (0.7-r0) (9/23) Purging g++ (5.3.0-r0) (10/23) Purging gcc (5.3.0-r0) (11/23) Purging binutils (2.25.1-r0) (12/23) Purging isl (0.14.1-r0) (13/23) Purging libatomic (5.3.0-r0) (14/23) Purging libc-dev (0.7-r0) (15/23) Purging musl-dev (1.1.12-r5) (16/23) Purging libstdc++ (5.3.0-r0) (17/23) Purging mpc1 (1.0.3-r0) (18/23) Purging mpfr3 (3.1.2-r0) (19/23) Purging gmp (6.1.0-r0) (20/23) Purging libgcc (5.3.0-r0) (21/23) Purging libedit (20150325.3.1-r3) (22/23) Purging binutils-libs (2.25.1-r0) (23/23) Purging libgomp (5.3.0-r0) Executing busybox-1.24.1-r7.trigger OK: 23 MiB in 32 packages ---> 829379018bc7 Removing intermediate container 09029fc13d73 Step 5 : ADD . /app ---> 66705b32dc48 Removing intermediate container c7f73596c9ae Step 6 : RUN chown -R nobody:nogroup /app
• 22.
  © 2015 Kontena,Inc. ---> Running in be356cda2cd6 ---> 0673c22b8d74 Removing intermediate container be356cda2cd6 Step 7 : USER nobody ---> Running in fd495cb3838a ---> 83cb7493aa53 Removing intermediate container fd495cb3838a Step 8 : ENV RACK_ENV production ---> Running in edac524bbd44 ---> e3b6c26647b2 Removing intermediate container edac524bbd44 Step 9 : EXPOSE 9292 ---> Running in 4369855c3ab4 ---> 3d82b78a2213 Removing intermediate container 4369855c3ab4 Step 10 : WORKDIR /app ---> Running in 6172a5c18269 ---> e73df80077b5 Removing intermediate container 6172a5c18269 Successfully built e73df80077b5 [email protected] ~/helsinki-ruby-brigade/todo$
• 23.
  From Containers toMicroservices • Docker Compose • Tool for defining and running multi-container Docker applications • Services and their configurations are defined in YAML file(s)
• 24.
  docker-compose.yml © 2015 Kontena,Inc. version: '2’ services: web: image: kontena/todo-example:latest command: bundle exec puma -p 9292 -e production environment: - MONGODB_URI=mongodb://mongodb:27017/todo_production ports: - 9292:9292 links: - mongodb:mongodb mongodb: image: mongo:3.2 command: mongod --smallfiles
• 25.
  Rolling to Production •How big this app will be? How many users it will serve? • Do you want your application to be infrastructure agnostic or lean heavily on some cloud provider? • How to run databases or save other persistent data? • How to scale the application and handle load balancing? • How do you pass sensitive data to your application and where to store that data? • How the application can be deployed and updated with zero down-time? © 2015 Kontena, Inc.
• 26.
  Example
• 27.
  kontena.yml version: '2’ services: mongodb: image:mongo:3.2 instances: 3 stateful: true command: --replSet kontena –smallfiles hooks: post_start: - cmd: sleep 10 name: sleep instances: 1 oneshot: true - cmd: mongo --eval "printjson(rs.initiate());” name: rs_initiate instances: 1 oneshot: true - cmd: mongo --eval "printjson(rs.add('%{project}-mongodb-2'))” name: rs_add2 instances: 1 oneshot: true - cmd: mongo --eval "printjson(rs.add('%{project}-mongodb-3'))” name: rs_add3 instances: 1 oneshot: true
• 28.
  © 2015 Kontena,Inc. app: image: kontena/todo-example:latest links: - mongodb:mongodb - loadbalancer environment: - MONGODB_URI=mongodb://%{project}-mongodb-1.kontena.local:27017,%{project}-mongodb- 2.kontena.local:27017,%{project}-mongodb-3.kontena.local:27017/todo_production - KONTENA_LB_VIRTUAL_PATH=/ - KONTENA_LB_INTERNAL_PORT=9292 command: bundle exec puma -p 9292 -e production loadbalancer: image: kontena/lb:latest deploy: strategy: daemon ports: - 80:80
• 29.
  Deploying Application © 2015Kontena, Inc. [email protected] ~/helsinki-ruby- brigade/todo$ kontena app deploy
• 30.
  Scaling Application © 2015Kontena, Inc. [email protected] ~/helsinki-ruby- brigade/todo$ kontena app scale app 10
• 31.
  Resources • Todo Example:https://github.com/kontena/helsinki-meetup- hackathon • Getting started: http://www.kontena.io • GitHub: https://github.com/kontena/kontena • Gitter: https://gitter.im/kontena/kontena • Kontena Meetup: http://www.meetup.com/Kontena-Helsinki/ © 2015 Kontena, Inc.
• 32.
  Thank You! www.kontena.io
• 33.
  We are hiring! kontena.io/jobs