Implement CDN for Media Files with S3/R2 Integration

[Techhackontime999]

Description

Move user uploads (avatars, cover photos, post attachments, resumes) from local storage to a cloud CDN (AWS S3 or Cloudflare R2) for better performance, reliability, and scalability.

Requirements

• Configure Django storages for S3/R2 backend
• Migrate existing local media files to cloud storage
• Signed URLs for private files (resumes, chat attachments)
• Public URLs for avatars and post images
• Image optimization on upload (resize avatars to 400x400, compress post images)
• CDN caching headers (Cache-Control)
• Fallback to local storage if CDN is unavailable
• Management command to migrate existing files
• Environment variable configuration for bucket/keys

Files to Create/Modify

• linkup/professional_network/settings/base.py - Django storages S3 configuration
• linkup/core/media_storage.py - Custom storage backend with CDN support
• linkup/core/validators.py - Update file validators for cloud storage
• linkup/scripts/migrate_media_to_s3.py - Migration script

equirements.txt - Add django-storages, �oto3

• .env.example - Add S3 configuration variables

Acceptance Criteria

• Files upload to cloud storage
• Avatars and images served from CDN
• Private files use signed URLs with expiration
• Existing files are migrated
• Local fallback works if CDN is down