Kubernetes Training Application

This is a complete Kubernetes training setup with a Go frontend and backend application.

Structure

• backend/ - Go backend API service
• frontend/ - Go frontend web application
• k8s/ - Kubernetes configuration files

Building Docker Images

# Build backend
cd backend
docker build -t your-registry/backend:latest .
docker push your-registry/backend:latest

# Build frontend
cd ../frontend
docker build -t your-registry/frontend:latest .
docker push your-registry/frontend:latest

Deploying to Kubernetes

1. Update the image names in the deployment files to match your Docker registry.

2. Apply the configurations:

# Deploy backend
kubectl apply -f k8s/backend-deployment.yaml
kubectl apply -f k8s/backend-service.yaml

# Deploy frontend
kubectl apply -f k8s/frontend-deployment.yaml
kubectl apply -f k8s/frontend-service.yaml

# Deploy ingress
kubectl apply -f k8s/ingress.yaml

3. Add to your /etc/hosts file:

127.0.0.1 training.local

4. Access the application at http://training.local

Architecture

• Backend: REST API service on port 8080

  • /health - Health check endpoint
  • /api/data - Returns JSON data with request counter

• Frontend: Web UI on port 8081

  • Displays a simple web interface
  • Calls backend API via proxy endpoint
  • Shows backend responses

Kubernetes Resources

• Deployments: Manage replica sets for both services

  • Backend: 3 replicas
  • Frontend: 2 replicas

• Services: Internal networking

  • Backend: ClusterIP service on port 8080
  • Frontend: ClusterIP service on port 80

• Ingress: External access via NGINX ingress controller

  • Routes / to frontend
  • Routes /api to backend

Testing Locally

# Run backend locally
cd backend
go run main.go

# Run frontend locally (in another terminal)
cd frontend
BACKEND_URL=http://localhost:8080 go run main.go

Visit http://localhost:8081 to see the frontend.