Docker Deployment using Jenkins

A complete CI/CD pipeline setup using Jenkins, Docker, and Terraform to automate the build, deployment, and rollback of a full-stack open-source PoolsApp (mrpool404/poolsapp) using Docker containers application on the AWS EC2.

This repo features:

• A three-stage Jenkins pipeline
• Dockerized frontend and backend apps
• AWS-hosted EC2 instance with pre-installed Docker (via Terraform)
• Docker image versioning, tagging, and stable rollback
• Reusable Jenkins shared library logic

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🧰 Tech Stack

• Frontend: Angular
• Backend: Node.js
• Database: MongoDB
• Containerization: Docker

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📁 Project Structure

.
├── Jenkins
│ ├── 01_build_push_images.groovy           # Builds Docker images and pushes them to DockerHub
│ ├── 02_deploy_with_docker.groovy          # Deploys Docker containers to EC2 using docker-compose
│ ├── 03_rollback_handler.groovy            # Rollback pipeline triggered on deployment failure
│ ├── Deployment_Docker.groovy              # (Initial approach by me) Combined pipeline if needed
│ └── preInstalledDockerUbuntu.groovy       # Jenkins pipeline to provision Docker-ready EC2 via Terraform
├── Pools-App-Backend                       # Backend code (Node.js/Express or similar)
├── Pools-App-Frontend                      # Frontend code (Angular/React/Vue or similar)
├── Terraform
│ └── preInstalledDockerUbuntu.tf           # Terraform script to provision Docker-ready EC2
├── docker-compose.yml                      # Defines frontend, backend, and MongoDB services
├── README.md                               # You're here!
├── LICENSE
├── images                                
├── poolsapp-LICENSE
└── poolsapp-README.md                      # Original README from open-source poolsapp project

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Each part of the project is modular and easily extendable, with individual Jenkins pipelines for each phase of CI/CD, and infrastructure provisioning handled via Terraform.

⚙️ Prerequisites & Requirements

Before you can use this project, ensure the following tools and configurations are in place:

🛠️ Tools & Technologies

• Jenkins with:
  • SSH Agent Plugin
  • Pipeline Plugin
  • Credentials Plugin
• Docker
• AWS CLI
• Terraform v1.5+
• AWS Account with the following:
  • IAM Role for Terraform (role-arn-terrafomRM)
  • S3 Bucket named pools.app-bucket-by-terraform
  • Secrets Manager for:
    • Database credentials
    • Terraform role ARN
• GitHub repository:
  • This repo: git@github.com:kakarot404/docker_deployment_using_jenkins.git
  • Shared Jenkins library: jenkins-shared-lib
• DockerHub account with credentials stored in Jenkins (dockerhub-creds)

🔐 Jenkins Credentials Required

In Jenkins, configure the following credentials:

ID	Type	Purpose
dockerhub-creds	Username & Password	DockerHub login
deployKey_JenkinsDockerDeployemnt_git	SSH Private Key	GitHub clone over SSH
SSH-cred-jenkins-nginx	SSH Private Key	EC2 server access via SSH

✅ Note: All infrastructure is provisioned using Terraform and assumes you're deploying to AWS EC2 with Docker pre-installed.

☁️ Step 4: Infrastructure Provisioning with Terraform

This project provisions a Docker-ready EC2 instance using Terraform + EC2 Image Builder, triggered via a Jenkins pipeline. The instance is created with:

• Ubuntu 20.04
• Docker pre-installed
• AWS CLI v2 installed
• Logs uploaded to an S3 bucket

📂 Relevant Files

Terraform
└── preInstalledDockerUbuntu.tf

Jenkins
└── preInstalledDockerUbuntu.groovy

🧪 What the Jenkins Pipeline Does

The preInstalledDockerUbuntu.groovy pipeline:

1. Downloads the required Terraform file from this repo.
2. Retrieves the IAM role ARN from AWS Secrets Manager (role-arn-terrafomRM).
3. Executes terraform init and terraform apply to:
   • Launch an EC2 instance
   • Install Docker (if not already installed)
   • Install AWS CLI
   • Upload a hello-world Docker test log to S3

🛠️ How to Trigger the Pipeline

In Jenkins, create a pipeline job pointing to:

Jenkins/preInstalledDockerUbuntu.groovy

Make sure the Jenkins instance has the required AWS credentials or permissions to assume the role via role_arn.

⚙️ Terraform Variables

The following variables are passed at runtime:

Variable	            Description
assume_role_arn	        IAM role ARN for Terraform
bucket_name	            S3 bucket for logs

🚀 Output

Once the pipeline completes:

A new EC2 instance is launched with Docker ready.

Its public IP is returned via Terraform output.

Docker’s test container log is uploaded to s3://pools.app-bucket-by-terraform/logs/hello_output.log.

🔁 Step 5: Jenkins Pipeline Structure & Flow

This repository follows a multi-stage Jenkins pipeline flow, triggered by GitHub webhooks and executed through Jenkins using a shared library.

🧱 Pipeline Overview

Stage	Pipeline Script	Trigger Condition	Description
01	01_build_push_images.groovy	GitHub Push (webhook)	Clones the repo, builds backend & frontend Docker images, and pushes them to DockerHub.
02	02_deploy_with_docker.groovy	After successful Stage 01	Fetches docker-compose.yml and metadata, transfers files to EC2, and deploys containers.
03	03_rollback_handler.groovy	On Stage 02 failure	Performs rollback to last known stable images if deployment fails.

📍 All Jenkins pipelines use this shared Jenkins library.

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🔁 Flow Diagram

GitHub Push
    ⬇️
01_build_push_images.groovy
    ⬇️ (on success)
02_deploy_with_docker.groovy
    ⬇️ (on failure)
03_rollback_handler.groovy

📌 Build Metadata & Secrets

• Build metadata like GIT_COMMIT, IMAGE_TAG, and BUILD_TIMESTAMP are stored in S3 for reference and rollback.

• AWS Secrets Manager is used to retrieve environment variables and credentials securely.

📤 DockerHub Usage

All Docker images are:

Tagged with the short commit hash and timestamp (<commit>-<timestamp>)

Pushed as :latest and :stable tags for traceability and rollback

📄 Example Artifact Uploads

    Type	          File	                                S3 Path
Metadata	    latest_build.json	        s3://pools.app-bucket-by-terraform/test/artifact/
Compose File	docker-compose.yml	        s3://pools.app-bucket-by-terraform/test/artifact/
Health Log	    output.log	                s3://pools.app-bucket-by-terraform/test/
Rollback Logs	rollback-<timestamp>.log	s3://pools.app-bucket-by-terraform/test/logs/

✍️ Author

Er. Powar Shubham S

GitHub: kakarot404

Docker Hub: https://hub.docker.com/repositories/kakarot404