AWS Builder Challenge #2 - CDK Infrastructure

This CDK project creates a complete, production-ready AWS infrastructure for Ajit N K's personal website as part of AWS Builder Challenge #2. The architecture follows AWS Well-Architected Framework principles with emphasis on security, cost optimization, and operational excellence.

🏗️ Architecture Overview

Core Infrastructure Components

• 🌐 Route 53: DNS management with custom domain (ajitnk.in)
• 🪣 Amazon S3: Private bucket with encryption, versioning, and lifecycle policies
• ⚡ CloudFront: Global CDN with custom domain, SSL certificate, and security headers
• 🔧 AWS Lambda: Serverless contact form processing with input validation
• 🚪 API Gateway: RESTful API with throttling and CORS configuration
• 📧 Amazon SNS: Email notifications for contact form submissions
• 🔒 AWS Certificate Manager: SSL/TLS certificates for HTTPS

Architecture Diagram

┌─────────────┐    ┌──────────────┐    ┌─────────────┐
│   Route 53  │───▶│  CloudFront  │───▶│  S3 Bucket  │
│     DNS     │    │     CDN      │    │   Website   │
└─────────────┘    └──────────────┘    └─────────────┘
                           │
                           ▼
                   ┌──────────────┐    ┌─────────────┐
                   │ API Gateway  │───▶│   Lambda    │
                   │   REST API   │    │ Contact Form│
                   └──────────────┘    └─────────────┘
                                              │
                                              ▼
                                       ┌─────────────┐
                                       │     SNS     │
                                       │ Notifications│
                                       └─────────────┘

🚀 Quick Start

Prerequisites

Ensure you have the following installed and configured:

# Install AWS CDK CLI globally
npm install -g aws-cdk@2.87.0

# Configure AWS credentials (choose one method)
aws configure  # Interactive configuration
# OR
export AWS_ACCESS_KEY_ID=your-access-key
export AWS_SECRET_ACCESS_KEY=your-secret-key
export AWS_DEFAULT_REGION=us-east-1

# Verify AWS configuration
aws sts get-caller-identity

Installation & Setup

# Clone and navigate to project
cd aws-builder-challenge-cdk

# Install dependencies
npm install

# Verify TypeScript compilation
npm run build

# Synthesize CloudFormation templates (recommended for validation)
cdk synth

First-Time Deployment

# Bootstrap CDK in your AWS account (one-time setup)
cdk bootstrap

# Deploy all stacks
npm run deploy

# Or deploy with custom domain parameter
cdk deploy --parameters domainName=ajitnk.in

# Monitor deployment progress
# Deployment typically takes 15-20 minutes due to CloudFront distribution creation

📋 Post-Deployment Steps

After deployment, CDK will output Route 53 name servers. Update your domain registrar (GoDaddy) with these name servers:

1. Go to GoDaddy DNS Management
2. Change name servers to the Route 53 name servers from CDK output
3. Wait 5-15 minutes for DNS propagation
4. Check email for SNS subscription confirmation
5. Upload website files using the automation scripts

🎯 CDK Outputs

The stack provides these outputs for automation scripts:

• WebsiteBucketName: S3 bucket name for file uploads
• CloudFrontDistributionId: For cache invalidation
• WebsiteUrl: Final website URL (https://ajitnk.in)
• ApiGatewayUrl: Contact form API endpoint
• Route53NameServers: Name servers for GoDaddy configuration
• SNSTopicArn: Email notification topic

💰 Cost Optimization

The infrastructure is optimized for AWS Free Tier:

• S3: Versioning with lifecycle rules
• CloudFront: Price Class 100 (US, Canada, Europe only)
• Lambda: 256MB memory, 30s timeout
• API Gateway: Throttling configured
• Route 53: ~$0.50/month (only paid service)

🔒 Security Features

• Private S3 bucket with Origin Access Control (OAC)
• HTTPS enforcement via CloudFront
• Security headers (HSTS, CSP, X-Frame-Options)
• Input validation and sanitization in Lambda
• Rate limiting on API Gateway
• Encrypted S3 storage

🛠️ Development

Useful Commands

npm run build     # Compile TypeScript to JS
npm run watch     # Watch for changes and compile
npm run test      # Run unit tests
npm run deploy    # Build and deploy all stacks
npm run destroy   # Delete all stacks
npm run bootstrap # Bootstrap CDK (one-time setup)
npm run diff      # Compare deployed stack with current state
npm run synth     # Emit the synthesized CloudFormation template

# Direct CDK commands
cdk deploy        # Deploy this stack to your default AWS account/region
cdk diff          # Compare deployed stack with current state
cdk synth         # Emit the synthesized CloudFormation template
cdk destroy       # Delete the stack

Development Workflow

For efficient development, follow this workflow:

# 1. Make changes to your CDK code
# 2. Synthesize to validate (recommended over npm run build)
cdk synth

# 3. Check differences before deployment
cdk diff

# 4. Deploy changes
npm run deploy

Important: Use cdk synth instead of npm run build for validation as it:

• Automatically compiles TypeScript when needed
• Validates CDK constructs and catches deployment issues
• Generates CloudFormation templates for inspection
• Provides more informative error messages

📁 Project Structure

lib/
├── website-stack.ts      # Main stack orchestration
├── dns-stack.ts          # Route 53 hosted zone
├── s3-stack.ts          # S3 bucket configuration
├── cloudfront-stack.ts  # CloudFront distribution and SSL
└── api-stack.ts         # Lambda + API Gateway + SNS

bin/
└── app.ts               # CDK app entry point

cdk.out/                 # Generated CloudFormation templates
node_modules/            # Dependencies
package.json             # Project configuration and scripts
tsconfig.json           # TypeScript configuration
cdk.json                # CDK configuration

🏷️ Resource Tagging

All resources are tagged for cost tracking and organization:

• Project: AWS-Builder-Challenge-2
• Owner: Ajit-N-K
• Environment: Production
• Service: [S3, CloudFront, Lambda, etc.]
• Purpose: [Website-Storage, Website-CDN, etc.]

🔧 Configuration

The stack accepts these parameters:

• domainName: Custom domain name (default: ajitnk.in)

Example with custom domain:

cdk deploy --parameters domainName=yourdomain.com

📞 Contact Form Integration

The contact form backend includes:

• Input validation (name, email, message required)
• HTML sanitization to prevent XSS
• Rate limiting for security
• Email notifications via SNS
• CORS configuration for web integration

🌐 DNS Configuration

After deployment:

1. Note the Route 53 name servers from CDK output
2. Update your domain registrar's name servers
3. DNS propagation typically takes 5-15 minutes
4. Both ajitnk.in and www.ajitnk.in will work

📊 Monitoring

Basic monitoring is included:

• CloudWatch metrics for all services
• Lambda function logs
• API Gateway access logs
• CloudFront access logs (optional)

🔍 Troubleshooting

Common Issues

Deployment fails with "Domain already exists":

• Check if Route 53 hosted zone already exists
• Ensure domain name parameter matches your actual domain

CloudFront distribution takes too long:

• CloudFront distributions typically take 15-20 minutes to deploy
• This is normal AWS behavior, not a project issue

SNS email not received:

• Check spam folder
• Confirm email subscription from AWS SNS
• Verify SNS topic ARN in outputs

Website not accessible:

• Ensure DNS propagation is complete (5-15 minutes)
• Check CloudFront distribution status
• Verify S3 bucket has website files uploaded

Debug Commands

# Check stack status
aws cloudformation describe-stacks --stack-name WebsiteStack

# View CloudFormation events
aws cloudformation describe-stack-events --stack-name WebsiteStack

# Check CDK differences
cdk diff

# Validate CloudFormation template
cdk synth > template.yaml
aws cloudformation validate-template --template-body file://template.yaml

🎯 AWS Builder Challenge Compliance

This infrastructure demonstrates:

• ✅ Infrastructure as Code (CDK)
• ✅ Serverless architecture
• ✅ Security best practices
• ✅ Cost optimization
• ✅ Professional custom domain
• ✅ Global content delivery
• ✅ Working contact form
• ✅ HTTPS encryption

🚀 Next Steps

After successful deployment:

1. Upload Website Content: Use the provided S3 bucket name to upload your website files
2. Test Contact Form: Verify the API Gateway endpoint works correctly
3. Monitor Costs: Use AWS Cost Explorer to track spending
4. Set Up Alerts: Configure CloudWatch alarms for monitoring
5. Backup Strategy: Consider implementing automated backups for critical data

📚 Additional Resources

• AWS CDK Documentation
• AWS Well-Architected Framework
• AWS Free Tier
• CloudFront Documentation
• Route 53 Documentation

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

👤 Author

Ajit N K (@ajitnk2006)

• Website: ajitnk.in
• AWS Builder Challenge #2 Submission

Ready for AWS Builder Challenge #2 submission! 🚀