# Multi-Tenant Architecture Audit

**Date:** November 29, 2025  
**Auditor:** GitHub Copilot  
**Branch:** feat/multi-tenannt  
**Scope:** Full stack audit from Web UI to REST API to Storage

---

## Executive Summary

This audit examines the multi-tenant implementation in LightRAG, covering:
- **Web UI Layer** (React/TypeScript frontend)
- **REST API Layer** (FastAPI backend)
- **Storage Layer** (PostgreSQL, Redis, Vector DBs)

## Architecture Overview

```
┌─────────────────────────────────────────────────────────────────┐
│                         Web UI Layer                             │
│  ┌─────────────┐  ┌──────────────┐  ┌─────────────────────────┐ │
│  │ TenantStore │  │ API Client   │  │ DocumentManager/Query   │ │
│  │ (Zustand)   │◄─┤ (Axios)      │◄─┤ Components              │ │
│  └─────────────┘  └──────────────┘  └─────────────────────────┘ │
│         │                │                      │                │
│         └────────────────┼──────────────────────┘                │
│                          ▼                                       │
│  ┌───────────────────────────────────────────────────────────┐  │
│  │           HTTP Headers: X-Tenant-ID, X-KB-ID              │  │
│  └───────────────────────────────────────────────────────────┘  │
└────────────────────────────────┬────────────────────────────────┘
                                 │
                                 ▼
┌─────────────────────────────────────────────────────────────────┐
│                        REST API Layer                            │
│  ┌──────────────┐  ┌───────────────────┐  ┌──────────────────┐  │
│  │ Middleware   │  │ Dependencies      │  │ Route Handlers   │  │
│  │ (Tenant     │──▶│ (get_tenant_ctx)  │──▶│ (Query/Doc/etc) │  │
│  │  Context)    │  │                   │  │                  │  │
│  └──────────────┘  └───────────────────┘  └──────────────────┘  │
│                           │                        │             │
│                           ▼                        ▼             │
│  ┌──────────────────────────────────────────────────────────┐   │
│  │              TenantRAGManager                             │   │
│  │  - Per-tenant LightRAG instances                          │   │
│  │  - LRU caching with isolation                            │   │
│  │  - User access verification                               │   │
│  └──────────────────────────────────────────────────────────┘   │
└────────────────────────────────┬────────────────────────────────┘
                                 │
                                 ▼
┌─────────────────────────────────────────────────────────────────┐
│                       Storage Layer                              │
│  ┌─────────────────┐  ┌──────────────┐  ┌──────────────────┐    │
│  │ PostgreSQL      │  │ Redis        │  │ Vector DBs       │    │
│  │ - tenant_id     │  │ - Namespace  │  │ - Metadata       │    │
│  │ - kb_id columns │  │   prefixes   │  │   filtering      │    │
│  │ - Composite PK  │  │              │  │                  │    │
│  └─────────────────┘  └──────────────┘  └──────────────────┘    │
└─────────────────────────────────────────────────────────────────┘
```

## Audit Components

### 1. Web UI Layer
- [ ] Tenant store state management
- [ ] API client header propagation
- [ ] Tenant/KB selection persistence
- [ ] Cross-component context sharing
- [ ] Document filtering by tenant/KB
- [ ] Query scoping by tenant/KB

### 2. REST API Layer
- [ ] Middleware tenant context extraction
- [ ] Dependency injection for tenant context
- [ ] Route handler tenant awareness
- [ ] TenantRAGManager isolation
- [ ] TenantService operations
- [ ] User access verification

### 3. Storage Layer
- [ ] PostgreSQL multi-tenant schema
- [ ] Redis namespace isolation
- [ ] Vector DB metadata filtering
- [ ] Composite key enforcement
- [ ] Cross-tenant data access prevention

## Test Environment Setup

**Configuration:**
- Web UI: Local development (not Docker)
- REST API: Local development (not Docker)
- Database: Docker container (PostgreSQL + pgvector)
- Redis: Docker container

## Documents in this Audit

1. `00-audit-overview.md` - This overview document
2. `01-test-protocol.md` - Detailed test protocol and setup instructions
3. `02-webui-audit.md` - Web UI layer findings
4. `03-api-audit.md` - REST API layer findings
5. `04-storage-audit.md` - Storage layer findings
6. `05-test-execution-log.md` - Test execution progress and results
7. `06-issues-found.md` - Issues discovered during audit
8. `07-recommendations.md` - Final recommendations

## Key Files Under Audit

### Web UI
- `lightrag_webui/src/stores/tenant.ts` - Tenant state management
- `lightrag_webui/src/api/client.ts` - Axios interceptor for headers
- `lightrag_webui/src/api/tenant.ts` - Tenant/KB API functions
- `lightrag_webui/src/features/DocumentManager.tsx` - Document operations
- `lightrag_webui/src/features/ChatQueryPanel.tsx` - Query operations

### REST API
- `lightrag/api/dependencies.py` - Tenant context extraction
- `lightrag/api/routers/tenant_routes.py` - Tenant CRUD
- `lightrag/api/routers/document_routes.py` - Document operations
- `lightrag/api/routers/query_routes.py` - Query operations
- `lightrag/tenant_rag_manager.py` - RAG instance management
- `lightrag/services/tenant_service.py` - Tenant business logic

### Storage
- `lightrag/kg/postgres_impl.py` - PostgreSQL storage
- `lightrag/kg/postgres_tenant_support.py` - Tenant SQL utilities
- `lightrag/kg/redis_tenant_support.py` - Redis namespace utilities
- `lightrag/kg/vector_tenant_support.py` - Vector DB utilities