🚀 AetherLink

A modern, secure file transfer system with P2P capabilities and share ID-based access control.

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🔐 NEW: Share ID Security System

Files are now protected by unique Share IDs!

• 🔑 32-character hex IDs - Cryptographically secure
• 🛡️ Access control - Only users with Share ID can access files
• 🚫 No bypass - Server validates all requests
• ✅ Tested & ready - See TEST_RESULTS.md

How it works:

1. Upload file → Get Share ID
2. Share ID with recipient
3. Recipient enters Share ID → Access files

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What This Is

A distributed file transfer platform that chunks files for reliable uploads with automatic resume, hash-based integrity checks, and live progress updates via Server-Sent Events.

Tech Stack

Frontend (Next.js 16)

• Framework: React 19, TypeScript 5, Next.js 16
• Styling: Tailwind CSS 4, Lucide React icons
• Features: Drag-drop file upload, progress bars, parallel chunk uploads
• Security: xxHash client-side hashing (per-chunk + full file)
• Real-time: SSE for live progress updates
• Persistence: localStorage for resumable sessions

Backend (Go - Orchestrator)

• Framework: Fiber v2 (REST + SSE)
• Storage: File-based chunked storage in ./storage/<uploadID>/
• Endpoints:
  • POST /init - Initialize upload session
  • PUT /upload/:uploadID/:idx - Upload chunk with hash validation
  • GET /status/:uploadID - Query received chunks (resume support)
  • POST /complete/:uploadID - Reassemble & verify file
  • GET /events/:uploadID - SSE progress stream
  • GET /static - Download assembled files
• Security: Per-chunk xxHash validation, final file hash verification
• Metadata: Hash tracking (.xxhash)

Go Client (CLI)

• Purpose: Command-line bulk uploader
• Config: 5KB chunks, 4 parallel workers, 5 retry attempts
• Features: Resume from interruption, exponential backoff

Features

• ✅ Chunked Upload: 1MB chunks (configurable)
• ✅ Resume Support: Query received chunks, skip completed ones
• ✅ Integrity Checks: xxHash validation per chunk + full file
• ✅ Parallel Upload: Multi-worker chunk upload for faster transfers
• ✅ Real-time Progress: SSE broadcast to all clients
• ✅ Auto-reassembly: Server stitches chunks on /complete
• ✅ Retry Logic: Exponential backoff (up to 6 attempts)
• ✅ CORS Enabled: Configured for localhost:3000

Architecture

┌─────────────┐         ┌──────────────┐         ┌─────────────┐
│   Browser   │◄───SSE──┤ Orchestrator │◄────────┤  CLI Client │
│  (Next.js)  │────────►│   (Fiber)    │         │    (Go)     │
└─────────────┘  REST   └──────────────┘         └─────────────┘
     │                         │
     │                         ▼
     │                  ┌─────────────┐
     └─────────────────►│   Storage   │
          Download      │  (chunks)   │
                        └─────────────┘

Current State

• ✅ Fully functional upload/download system
• ✅ Multiple completed upload sessions in storage
• ✅ Test files successfully transferred (25+ chunks processed)
• ✅ Real-time progress tracking operational
• ✅ Resume capability tested and working