veza/k8s/cdn

CDN Configuration

This directory contains Kubernetes configurations for Content Delivery Network (CDN) setup to optimize delivery of static assets and audio files.

Overview

CDN configuration provides:

• Faster asset delivery through edge caching
• Reduced origin server load
• Better global performance with geographically distributed caching
• Optimized caching for different asset types

Components

nginx-cdn-config

• Optimized nginx configuration for CDN integration
• Long cache headers for static assets
• CORS headers for cross-origin requests
• Range request support for audio/video streaming

cdn-configmap

• General CDN configuration
• Provider selection
• Cache TTL settings
• Feature toggles

Provider-Specific Configs

• cloudflare-config.yaml: Cloudflare CDN configuration
• cloudfront-config.yaml: AWS CloudFront CDN configuration

Supported CDN Providers

Cloudflare

• Pros: Easy setup, free tier, DDoS protection, global network
• Cons: Limited customization on free tier
• Best for: Small to medium deployments

AWS CloudFront

• Pros: Highly customizable, integrates with AWS services, pay-per-use
• Cons: More complex setup, AWS account required
• Best for: AWS-based infrastructure

Generic CDN

• Pros: Works with any CDN provider
• Cons: Manual configuration required
• Best for: Custom CDN solutions

Deployment

1. Apply nginx CDN Configuration

kubectl apply -f k8s/cdn/nginx-cdn-config.yaml

Update frontend deployment to use this config:

volumeMounts:
- name: nginx-cdn-config
  mountPath: /etc/nginx/conf.d/cdn.conf
  subPath: nginx-cdn.conf
volumes:
- name: nginx-cdn-config
  configMap:
    name: nginx-cdn-config

2. Apply CDN ConfigMap

kubectl apply -f k8s/cdn/cdn-configmap.yaml

3. Configure CDN Provider

Cloudflare

1. Update cloudflare-config.yaml with your zone ID
2. Create secret with API token:

   kubectl create secret generic cloudflare-secrets \
     --from-literal=api-token=your-api-token \
     -n veza-production
   

3. Apply configuration:

   kubectl apply -f k8s/cdn/cloudflare-config.yaml
   

AWS CloudFront

1. Update cloudfront-config.yaml with your distribution ID
2. Create secret with AWS credentials:

   kubectl create secret generic aws-secrets \
     --from-literal=access-key-id=your-key \
     --from-literal=secret-access-key=your-secret \
     -n veza-production
   

3. Apply configuration:

   kubectl apply -f k8s/cdn/cloudfront-config.yaml
   

Configuration

Cache TTL Settings

Edit cdn-configmap.yaml to adjust cache TTLs:

# Static assets (JS, CSS, images, fonts)
cdn-cache-ttl: "31536000"  # 1 year

# Audio files
cdn-audio-cache-ttl: "2592000"  # 30 days

Enable/Disable CDN Features

# Enable CDN for static assets
cdn-assets-enabled: "true"

# Enable CDN for audio files
cdn-audio-enabled: "true"

# Enable CDN for images
cdn-images-enabled: "true"

Integration with Services

Frontend

The frontend should use CDN URLs for static assets. Update environment variables:

VITE_CDN_URL=https://cdn.veza.com
VITE_CDN_ENABLED=true

Backend API

The backend CDN service (internal/services/cdn_service.go) can generate CDN URLs:

cdnService := services.NewCDNService(services.CDNConfig{
    Provider: services.CDNProviderCloudflare,
    BaseURL:  "https://cdn.veza.com",
    Enabled:  true,
})

assetURL := cdnService.GetAssetURL("images", "logo.png")
audioURL := cdnService.GetAudioURL("track-123", "song.mp3")

Cache Invalidation

Manual Invalidation

# Invalidate specific paths
kubectl exec -it deployment/veza-backend-api -n veza-production -- \
  /app/veza-api cdn invalidate /static/js/app.js /audio/track-123/song.mp3

Automatic Invalidation

The backend CDN service supports automatic cache invalidation on content updates. Configure in cdn-configmap.yaml:

cdn-invalidation-on-update: "true"

Testing

Verify CDN Headers

# Check static asset headers
curl -I https://cdn.veza.com/static/js/app.js

# Should see:
# Cache-Control: public, immutable, max-age=31536000
# X-CDN-Cache-Status: HIT

Test CORS

# Test CORS for audio files
curl -H "Origin: https://app.veza.com" \
     -H "Access-Control-Request-Method: GET" \
     -H "Access-Control-Request-Headers: Range" \
     -X OPTIONS \
     https://cdn.veza.com/audio/track-123/song.mp3

Check Cache Status

# View CDN cache headers
curl -I https://cdn.veza.com/static/css/app.css | grep -i cache

Monitoring

CDN Metrics

Monitor CDN performance:

• Cache hit ratio
• Origin requests
• Bandwidth usage
• Response times

Set Up Alerts

Alert on:

• Low cache hit ratio (< 80%)
• High origin requests
• CDN errors

Best Practices

1. Use long cache TTLs for immutable assets (JS, CSS with hashes)
2. Use shorter TTLs for dynamic content
3. Enable compression (gzip, brotli) at CDN level
4. Use CDN for audio/video to reduce origin load
5. Monitor cache hit rates and adjust TTLs accordingly
6. Invalidate cache when deploying new versions
7. Use versioned URLs for assets (e.g., /static/js/app-v1.2.3.js)

Troubleshooting

Assets Not Loading from CDN

1. Check CDN configuration:

   kubectl get configmap cdn-config -n veza-production -o yaml
   

2. Verify CDN base URL is correct

3. Check DNS resolution for CDN domain

4. Verify CORS headers are set correctly

Cache Not Working

1. Check cache headers in response:

   curl -I https://cdn.veza.com/static/js/app.js
   

2. Verify CDN provider settings

3. Check cache TTL configuration

4. Verify CDN is enabled in configmap

CORS Issues

1. Check CORS headers in nginx config
2. Verify Access-Control-Allow-Origin is set
3. Check preflight OPTIONS requests are handled
4. Verify allowed methods and headers

Additional Resources

• Cloudflare CDN Documentation
• AWS CloudFront Documentation
• nginx CDN Configuration