This document discusses dockerizing Rails applications for repeatable deployments with zero downtime. It introduces Docker, explaining that containers provide lightweight virtualization at the OS level compared to traditional virtual machines. Rails principles of programmer happiness and convention over configuration are discussed. The document demonstrates dockerizing a sample ToDo app using Dockerfiles, images, containers, Docker Compose for orchestration, and Docker Swarm for scaling across multiple nodes. It compares monolith vs microservices architectures and Swarm vs Kubernetes orchestration tools.

1. Dockerizing
Rails

2. Dockerizing Rails
…or any other framework

3. Why Dockerize?
◎ Have many commands do you use to setup your
development environment?
◎ How easy is it to deploy your app?
◎ How much downtime does your deploy cost?
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4. Hello!
I’m Igbanam
◎ S.S.E at Andela
◎ Poet
◎ @yaasky on Twitter
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5. “
dockerizing apps
repeatable deployments
at your fingertips
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6. 0.
Zero Downtime
What and Why
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7. “
The standard for website
availability is the five nines
99.99999% uptime
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8. Deployments
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9. Today, we shall talk about
◎ Rails
○ Fast Prototyping
○ Continuous Deployment
◎ Docker
○ Compose
○ Swarm (vs. Kubernetes)
◎ Live Deployments
○ Demo
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10. 1.
Ruby on Rails
Most popular Ruby framework
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11. 11

12. 12
Ruby on Rails Principles
◎ Programmer Happiness
◎ Convention over
Configuration
◎ Progress over Stability
More at Rails Doctrine

13. Release Pipeline
Code
Test
Deploy
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14. Deployment pipeline
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Production 1
SCM
Development

15. 2.
Docker
Containerizing
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16. 16
Brief History of Deployments
◎ FTP (Shared Hosting)
◎ Rsync
◎ SSH + Script
○ Ruby’s Capistrano
◎ Virtual Machine
○ Platform-as-a-Service
◎ Containers

17. 17

18. Virtualization
◎ Hardware-level
◎ Heavyweight
◎ Slow provisioning
◎ Limited Performance
◎ Fully isolated
◎ More secure
Difference between Virtualization and Containerization
Containerization
◎ OS-level
◎ Lightweight
◎ Real time provisioning and
scalability
◎ Native performance
◎ Process-level isolation
◎ Less secure (ish)
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19. 19
Images Container Engine Swarm

20. Docker Constituents
◎ Images
◎ Containers
◎ Engine
◎ Swarm
Image
An image is a blueprint of a
machine. Here we describe
configurations and constituents
of the machine.
Think of it as a “class”
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21. Dockerfile (snippet)
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22. Docker Constituents
◎ Images
◎ Containers
◎ Engine
◎ Swarm
Container
A container is an instantiated
image.
Complete isolated process
environment where the service
(your app) runs.
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23. Container Build Process
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24. Docker Constituents
◎ Images
◎ Containers
◎ Engine
◎ Swarm
Engine
Containers need a host machine
to run on. The engine serves this
purpose.
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25. Engine Evaluation
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26. Docker Constituents
◎ Images
◎ Containers
◎ Engine
◎ Swarm
Swarm
A collection of engines (as
nodes) within a cluster. Also an
orchestration tool for
deployments
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27. Docker Constituents
Volumes
Filesystems within your containers
Nodes
Engines within a Swarm
Stacks
Managing services in a swarm.
Compose is the definition.
Services
…provided by the container. This
could be your app.
Networks
Define the topology of your
platform.
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28. Docker Hub
Repository for Docker Images.
Opensource, and free.
hub.docker.com
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29. 3.
Docker + Rails
Let's put our app in a box
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30. Small ToDo App (Underbelly)
Read Database (SQL)
Write DB (NoSQL)
Cache (Redis)
MSG Broker (Kafka)
API Server (Rails)
Logs
Monitoring Tools
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31. “
“Logic Complexity is solved with
abstraction. Process Complexity is
solved with automation.”
~ I’m paraphrasing Uncle Bob 🤓
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32. Docker
Compose
Orchestrate everything.
Let the computer compute.
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33. 4.
Scale
Small App, Big Cloud
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34. Successful Software Setups
ProcessesTeam Architecture
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35. Three Pillars of Good Software
Team
◎ Conway's Law
◎ Agile teams
◎ Autonomy
Processes
◎ Collaboration
◎ Testing
◎ Releases
Architecture
◎ Monolith
◎ Distributed
○ Microservices
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36. Monolith or Microservices
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or
Monolith by Rene Aigner Stonehenge by Unknown

37. “
You are the “Dev” in DevOps
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38. Swarm
◎ Familiar API
◎ Built on building blocks
◎ Optimized for speed
◎ Built-in load-balancing
◎ Volumes across containers
◎ Automatic Network Config
◎ Self-discovery within cluster
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Swarm vs. Kubernetes
Kubernetes
◎ Novel API
◎ Isolated Concept
◎ Optimized for resilience
◎ Manual load-balancing
◎ Volume within pods
◎ Manual Networking
◎ Containers muse identify

39. Thanks!
Any questions?
@yaasky
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