cdn-integration

Cdn Integration

Skill Profile

(Select at least one profile to enable specific modules)

• DevOps
• Backend
• Frontend
• AI-RAG
• Security Critical

Overview

Content Delivery Networks (CDNs) distribute content across multiple geographical locations to reduce latency, improve load times, and reduce bandwidth costs. This skill covers CloudFront and Cloudflare CDN integration patterns.

Why This Matters

CDNs are essential for modern web applications to provide fast, reliable content delivery to users worldwide. By caching content at edge locations closer to users, CDNs significantly reduce latency, improve user experience, and reduce load on origin servers. This skill provides comprehensive patterns for integrating with major CDN providers (CloudFront and Cloudflare) including setup, caching strategies, invalidation, security, and optimization.

Core Concepts & Rules

1. Core Principles

• Follow established patterns and conventions
• Maintain consistency across codebase
• Document decisions and trade-offs

2. Implementation Guidelines

• Start with the simplest viable solution
• Iterate based on feedback and requirements
• Test thoroughly before deployment

Inputs / Outputs / Contracts

• Inputs:
  • <e.g., env vars, request payload, file paths, schema>
• Entry Conditions:
  • <Pre-requisites: e.g., Repo initialized, DB running, specific branch checked out>
• Outputs:
  • <e.g., artifacts (PR diff, docs, tests, dashboard JSON)>
• Artifacts Required (Deliverables):
  • <e.g., Code Diff, Unit Tests, Migration Script, API Docs>
• Acceptance Evidence:
  • <e.g., Test Report (screenshot/log), Benchmark Result, Security Scan Report>
• Success Criteria:
  • <e.g., p95 < 300ms, coverage ≥ 80%>

Skill Composition

• Depends on: None
• Compatible with: None
• Conflicts with: None
• Related Skills: None

Quick Start / Implementation Example

1. Review requirements and constraints
2. Set up development environment
3. Implement core functionality following patterns
4. Write tests for critical paths
5. Run tests and fix issues
6. Document any deviations or decisions

# Example implementation following best practices
def example_function():
    # Your implementation here
    pass

Assumptions

• Origin servers are accessible from CDN edge locations
• SSL certificates are properly configured for custom domains
• S3 buckets are properly configured with appropriate policies
• DNS records are properly configured to point to CDN

Compatibility

• CloudFront: Compatible with S3, custom origins, ALB/ELB
• Cloudflare: Compatible with any HTTP/HTTPS origin
• Terraform: AWS provider 4.x+, Cloudflare provider 3.x+

Test Scenario Matrix

Technical Guardrails & Security Threat Model

1. Security & Privacy (Threat Model)

• Top Threats: Injection attacks, authentication bypass, data exposure

• Data Handling: Sanitize all user inputs to prevent Injection attacks. Never log raw PII
• Secrets Management: No hardcoded API keys. Use Env Vars/Secrets Manager
• Authorization: Validate user permissions before state changes

2. Performance & Resources

• Execution Efficiency: Consider time complexity for algorithms
• Memory Management: Use streams/pagination for large data
• Resource Cleanup: Close DB connections/file handlers in finally blocks

3. Architecture & Scalability

• Design Pattern: Follow SOLID principles, use Dependency Injection
• Modularity: Decouple logic from UI/Frameworks

4. Observability & Reliability

• Logging Standards: Structured JSON, include trace IDs request_id
• Metrics: Track error_rate, latency, queue_depth
• Error Handling: Standardized error codes, no bare except
• Observability Artifacts:
  • Log Fields: timestamp, level, message, request_id
  • Metrics: request_count, error_count, response_time
  • Dashboards/Alerts: High Error Rate > 5%

Agent Directives

• Always validate CDN configuration before deployment
• Use appropriate cache headers for different content types
• Implement cache warming for critical assets
• Monitor CDN performance metrics

Definition of Done (DoD) Checklist

• Tests passed + coverage met
• Lint/Typecheck passed
• Logging/Metrics/Trace implemented
• Security checks passed
• Documentation/Changelog updated
• Accessibility/Performance requirements met (if frontend)

Anti-patterns

1. Wildcard invalidation: Avoid using /* for invalidation - it's slow and expensive
2. Long TTL for dynamic content: Don't cache dynamic content with long TTL
3. No cache headers: Always set cache headers to control caching behavior
4. Ignoring cache hit rates: Monitor and optimize cache hit rates
5. Direct origin access: Prevent direct access to origin when using CDN

Reference Links & Examples

• Internal documentation and examples
• Official documentation and best practices
• Community resources and discussions

Versioning & Changelog

• Version: 1.0.0
• Changelog:
  • 2026-02-22: Initial version with complete template structure