Java Containerized Application Deployment in Kubernetes

This repository contains the deployment files and instructions for deploying a Java application as a container in Kubernetes using Jenkins, GitHub, Docker, and Kubernetes.

Table of Contents

• Overview
• Prerequisites
• Project Structure
• Deployment Steps
• Configuration
• Accessing the Application
• Cleaning Up

Overview

This project demonstrates the deployment of a Java application as a container in Kubernetes using a CI/CD pipeline with Jenkins, GitHub for version control, Docker for containerization, and Kubernetes for orchestration.

Prerequisites

Before you begin, ensure you have the following prerequisites:

• Jenkins CI/CD pipeline configured with appropriate plugins and credentials.
• Docker installed on the Jenkins server or build machine.
• GitHub repository for your Java application code.
• Kubernetes cluster configured and accessible from Jenkins.

Project Structure

The project structure is as follows:

java-containerized-app/
├── Dockerfile
├── src/
│   ├── main ----
│   └── java - file ----
└── README.md
├── deploymentservice.yaml
├── kubernetes-cd.hpi
├── mvnw
├── mvnw.cmd
└── pom.xml

• Dockerfile: Contains instructions to build the Docker image for the Java application.
• deploymentservice.yaml: To create Deployement and Services in Kubernetes.
• pom.xml: java dependenices to run this application
• Jenkins file/: To create a pipeline for each stages.
• README.md: Instructions and documentation (you're reading it now).

Deployment Steps

1. Clone this repository to your Jenkins workspace or build machine:

   git clone https://github.com/your/repository.git

2. Configure Jenkins pipeline to build the Docker image using the provided Dockerfile.

3. Push the Docker image to a Docker registry (e.g., Docker Hub, AWS ECR).

4. Update Kubernetes deployment and service files (deployment.yaml, service.yaml) with your Docker image details.

5. Configure Jenkins to apply the Kubernetes deployment and service using kubectl commands.

Configuration

Jenkins Pipeline Configuration

• Set up a Jenkins pipeline with stages for building the Docker image, pushing to the registry, and deploying to Kubernetes.
• Use Jenkins environment variables or credentials to store sensitive information such as Docker registry credentials.

Kubernetes Configuration

• Update deployment.yaml with your Docker image repository and tag.
• Define Kubernetes resources such as CPU, memory limits, environment variables, etc., in the deployment file.
• Modify service.yaml for exposing the application via a Kubernetes service.

Accessing the Application

After successful deployment, access the Java application using the provided service URL or external IP exposed by Kubernetes.

Cleaning Up

To clean up resources:

1. Delete the Kubernetes deployment and service:

   kubectl delete -f kubernetes/deployment.yaml
   kubectl delete -f kubernetes/service.yaml

2. Remove the Docker image from the registry if no longer needed.