About / Overview

This is a full-stack Todo application. The focus of this project was Fullstack & DevOps experience.

This to-do application used the PERN stack (PostgreSQL, Express, React and Node.js) for development.

• Built a full-stack Todo app using TDD in AWS.
• Frontend hosted in an S3 bucket.
• CloudFront used as CDN service to cache website to localised nodes.
• Used Docker to configure and build a lightweight image.
• Deployed Docker image on ECR.
• Autoscaling ECS cluster to accommodate changes to traffic.
• Highly available by being deployed across multiple availability zones.
• Integrated a Load Balancer to manage traffic to any given node.
• RDS used to implement PostgreSQL database.
• Implemented an automated CI/CD pipeline using GitHub Actions, which deployed frontend assets to an S3 bucket, and built and deployed a new version of the backend image to ECS.
• Provisioned all the infrastructure in AWS as code using Terraform.
• Used a Postgres Test Container and Jest to learn integration testing.
• Used Playwright to learn end-to-end testing.

Current

Currently, I have removed the deployed application and re-doing this step using Infrastructure as Code (Terraform). In parallel, I am also creating migration scripts to create the database on application launch.

Difficulties?

PROBLEM 1:

Container build would fail to execute on AWS.

SOLUTION 1:

Failed exec was due to the way in which Docker images were being built. In my case, I was using an Apple Silicon M1 chip. By default Docker on M1 macbook would create linux/arm64 images, which would work only on the machines that are using ARM cpu architecture. But intel based machines use AMD architecture. As a result docker images built on M1 macbook might not work on intel based machines. So I needed to build docker images using linux/amd64 in order to deploy on AWS ECS.

Check your CPU Architecture:

uname -a

Docker Build Command:

docker buildx build --platform=linux/amd64 -t < image id >.dkr.< region >.amazonaws.com/< image name >:< tag > .

Optimisations

The Dockerfile was designed with layer caching in mind for optimised / faster builds.

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Useful Commands (for reference)

Pushing a Docker image AWS Docs

Authenticate your Docker client to the Amazon ECR registry to which you intend to push your image:

aws ecr get-login-password --region region | docker login --username AWS --password-stdin aws_account_id.dkr.ecr.region.amazonaws.com

Push the image using the docker push command:

docker push aws_account_id.dkr.ecr.us-west-2.amazonaws.com/my-repository:tag