Feature Specification: File Storage & Uploads

1. Overview & Vision

The File Storage feature provides the foundational ability to upload, store, and retrieve digital assets. It aims to be the "Hard Drive" of the VENI-AI ecosystem, offering high-performance, secure, and organization-scoped storage for all modules.

2. Personas & Stakeholders

Persona	Goal
User	Upload and manage personal and project files.
Admin	Manage organization-wide storage quota and assets.
Satellite Service	Programmatically store and retrieve files (e.g., HRM avatars).

3. User Stories

• As a user, I want to drag multiple documents into Drive so they are stored safely in the cloud.
• As a member, I want to download the latest version of a project brief to work offline.
• As an admin, I want to delete old files to free up organization storage space.

4. Functional Requirements (FR)

• REQ-DR-001: Multi-file upload support (Drag-and-Drop).
• REQ-DR-002: Maximum file size support up to 100MB.
• REQ-DR-003: MIME-type validation and original filename preservation.
• REQ-DR-004: Secure direct-to-S3 streaming for large uploads.

5. Non-Functional Requirements (NFR)

• Scalability: Support for millions of files per organization.
• Availability: 99.9% success rate for file retrieval.
• Security: Files MUST be encrypted at rest in the storage backend.

6. Business Logic & Rules

• Quota Check: Uploads are blocked if the organization's storage_quota is exceeded.
• Streaming: Files are streamed directly to S3 to minimize API memory usage.
• Consistency: Metadata is only committed to SQL after successful S3 confirmation.

7. User Interface (UI/UX)

• File Explorer: Grid and List views with metadata (size, date, owner).
• Upload Queue: Side-drawer showing active uploads and progress bars.
• Preview: Built-in viewer for Images, PDFs, and Plain Text.

8. Information Architecture

• Root "Drive" navigation.
• Nested folder structure (See Folder Org feature).

9. Data Model & Persistence

• Table: files.
• Backend: S3-compatible (MinIO / AWS S3).
• Pathing: s3://{orgId}/{fileId}_{filename}.

10. API & Service Layer

• POST /files (multipart/form-data)
• GET /files/:id/download (Redirects to presigned URL)
• DELETE /files/:id

11. Integration Patterns

• presigned URLs: Generated by the API for secure, time-bound direct downloads from S3.
• Inter-service: HRM uses the internal StorageService to manage avatars.

12. Security & Permissions

• RBAC: drive:read to view/download; drive:write to upload/delete.
• Isolation: Every request is validated against the user's organizationId.

13. Error Handling & Resilience

• Multipart Failures: Automated retry logic for failed chunks (planned).
• Graceful Error: User-friendly messages for "Quota Exceeded" or "File Too Large".

14. Performance & Scalability

• Parallel uploading for multiple files.
• CDN integration for public assets (planned for v1.5).

15. Globalization & i18n

• Support for non-Latin character sets in filenames (UTF-8).

16. Accessibility (a11y)

• Aria-live regions for upload progress announcements.
• Keyboard-accessible file selection and context menus.

17. Observability & Analytics

• Tracking of "Storage Consumption" trends per organization.
• Monitoring of "Upload Latency" and "Failure Rates".

18. Testing & Quality

• Integration tests using a local MinIO container.
• Stress testing for high-concurrency upload scenarios.

19. Constraints & Assumptions

• Assumes organization has an active subscription with storage quota.

20. Future Enhancements

• Video transcoding and streaming.
• Intelligent tagging using computer vision (v2).