Multi-Stage Docker Build: How to Build Production-Ready Docker Image

The source code is for the short course

Announcement: Course on Kubernetes

If you want to start deploying your containers to Kubernetes, especially on AWS EKS, check this course on Kubernetes that walkthrough creating Kubernetes cluster on AWS EKS using Terraform and deploying multiple related containers applications to Kubernetes and more. https://www.devteds.com/kubernetes-course-aws-eks-terraform

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This short course, the Multi-Stage Docker Build, is for Developers and DevOps engineers that have some basic knowledge of creating Dockerfile and building docker images, wanting to learn creating multi-stage Dockerfile to build production-ready docker images. In this free short course, we will step through,

• Dockerizing an exisitng application (a Rails application)
• Not too much into the Rails but give a quick walkthrough for Non-Rails developers
• Build Docker Image (without multi-stage), test and run the container locally
• A short overview of how the Dockerfile will be structured for multi-stage
• Transform the Dockerfile with multi-stage for development environment
• Extend to add more stages and build final, deployable and prod-ready image
• Using the deployable image, run container locally to test the prod-ready image

Course video link

Visit https://devteds.com to watch all the videos and courses on DevOps and Cloud courses.

Terminal Window Log

Code

mkdir ~/projs
git clone https://github.com/devteds/multi-stage-docker-build.git multi-stage-docker-build
cd multi-stage-docker-build

Build and Run locally

# Run on local
docker-compose build
docker-compose up

open http://localhost:3101/posts
open http://localhost:3101/admin

Build for prod and test

# stop all containers (Ctl + C)

docker build -t blog-app-prod --target=prod .

# uncomment blog-app-prod service and,
docker-compose up blog-app-prod
open http://localhost:3102/posts

Tools & Versions I used

• Ruby 3.1.2
• Ruby on Rails 7.0.3
• MySQL 5.7
• MacOS 12.0.1
• Docker 20.10.11
• Docker 1.29.2 (and v2)

References