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Docker for Rails Developers

Notes on the book Docker for Rails Developers, By Rob Isenberg, pubished by The Pragmatic Programmers



Highlights from the Table of Contents

Part I — Development

1. A Brave New World

  • Installing Docker
  • Verifying Your Install
  • Before We Begin
  • Running a Ruby Script Without Ruby Installed
  • Generating a New Rails App Without Ruby Installed

2. Running a Rails App in a Container

  • How Do We Run Our Rails App?
  • Defining Our First Custom Image
  • Building Our Image
  • Running a Rails Server with Our Image
  • Reaching the App: Publishing Ports
  • Binding the Rails Server to IP Addresses

3. Fine-Tuning Our Rails Image

  • Naming and Versioning Our Image
  • A Default Command
  • Ignoring Unnecessary Files
  • The Image Build Cache
  • Caching Issue 1: Updating Packages
  • Caching Issue 2: Unnecessary Gem Installs
  • The Finishing Touch

4. Describing Our App Declaratively with Docker Compose

  • Getting Started with Compose
  • Launching Our App
  • Mounting a Local Volume
  • Starting and Stopping Services
  • Other Common Tasks

5. Beyond the App: Adding Redis

  • Starting a Redis Server
  • Manually Connecting to the Redis Server
  • How Containers Can Talk to Each Other
  • Our Rails App Talking to Redis
  • Starting the Entire App with Docker Compose

6. Adding a Database: Postgres

  • Starting a Postgres Server
  • Connecting to Postgres from a Separate Container
  • Connecting Our Rails App to Postgres
  • Using the Database in Practice
  • Decoupling Data from the Container

7. Playing Nice with JavaScript

  • The JavaScript Front-End Options
  • Rails JavaScript Front End with Webpacker
  • Compiling Assets with Webpacker
  • A Hello World React App

8. Testing in a Dockerized Environment

  • Setting Up RSpec
  • Our First Test
  • Setting Up Rails System Tests
  • Running Tests That Rely on JavaScript
  • Debugging

9. Advanced Gem Management

  • The Downside to Our Existing Approach
  • Using a Gem Cache Volume

10. Some Minor Irritations

  • Rails tmp/pids/ Not Cleaned Up
  • Compose Intermittently Aborts with Ctrl-C

Part II — Toward Production

11. The Production Landscape

  • The “Ops” in DevOps
  • Container Orchestration
  • A Tale of Two Orchestrators: Swarm and Kubernetes
  • IaaS vs. CaaS
  • Provisioning Your Infrastructure
  • CaaS Platforms
  • Serverless for Containers
  • How to Decide What’s Right for Me?

12. Preparing for Production

  • Configuring a Production Environment
  • A Production Image: Precompiling Assets
  • Sharing Images

13. A Production-Like Playground

  • Creating Machines
  • Introducing Docker Swarm
  • Our First (Single Node) Swarm
  • Describing Our App to Swarm
  • Migrating the Database
  • Deploying Our App on a Swarm
  • Tasks and Swarm’s Scaling Model
  • Scaling Up the Service

14. Deploying to the Cloud

  • Creating a DigitalOcean Cluster
  • Deploying to Our DigitalOcean Swarm
  • Visualizing Containers
  • Scale Up the Web Service
  • Deploying to AWS Instead of DigitalOcean

Getting the Examples Source

tar zxvf

unzips into a code folder.

Credits and References

About LCK#146 dockerrailsbook
Project Source on GitHub Return to the Project Catalog

This page is a web-friendly rendering of my project notes shared in the LittleCodingKata GitHub repository.

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