Hello World App Deployment

Overview

This repository contains a simple "Hello World" web application written in Node.js, containerized using Docker, and deployed to a Kubernetes cluster using Helm.

Repository Structure

.
├── README.md
├── hello-world-app
│   ├── Dockerfile
│   ├── app.js
│   └── package.json
└── hello-world-chart
    ├── Chart.yaml
    ├── charts
    ├── templates
    │   ├── NOTES.txt
    │   ├── _helpers.tpl
    │   ├── deployment.yaml
    │   ├── hpa.yaml
    │   ├── ingress.yaml
    │   ├── service.yaml
    │   └── serviceaccount.yaml
    └── values.yaml

Prerequisites

Kubernetes cluster (local or remote)
kubectl (command-line tool for Kubernetes)
Helm (package manager for Kubernetes)
Docker (for building and managing containers)

Application Details

The "Hello World" application is a simple web server that responds with "Hello World" when accessed. It is built using Node.js and runs inside a Docker container.

How to Deploy

Step 1: Build the Docker Image

First, ensure you are in the root directory of the repository, where the hello-world-app directory is located. Then, build the Docker image:

docker build -t your-dockerhub-username/hello-world-app:latest ./hello-world-app

Step 2: Push the Docker Image to a Registry (Optional)

If you're using a public Docker registry like Docker Hub, push the image:

docker push your-dockerhub-username/hello-world-app:latest

Step 3: Deploy with Helm

Create a Namespace (if it doesn't exist):

kubectl create namespace hello-world-test

Update values.yaml in hello-world-chart. Ensure values.yaml is updated to point to your Docker image.

If it's in Dockerhub, it should look something like this:

image:
  repository: your-dockerhub-username/hello-world-app
  tag: latest
  pullPolicy: IfNotPresent

If the container image is on your machine, it should look something like this:

image:
  repository: hello-world-app
  tag: latest
  pullPolicy: IfNotPresent

Deploy the Helm Chart:

helm install hello-world-test ./hello-world-chart --namespace hello-world-test

Verify the Deployment:

kubectl get all --namespace hello-world-test

Step 4: Access the Web Application

Using External IP (LoadBalancer)

Get the External IP:

kubectl get svc --namespace hello-world-test

You should see an output similar to:

NAME                                       TYPE           CLUSTER-IP        EXTERNAL-IP    PORT(S)        AGE
hello-world-test-hello-world-chart         LoadBalancer   192.168.194.243   <external-ip>  80:31794/TCP   68s

Open Your Browser:

Navigate to http://<external-ip>:80

Using Port-Forwarding (Alternative)

Port-Forward the Service:

kubectl port-forward --namespace hello-world-test svc/hello-world-test-hello-world-chart 8080:80