# Multi-Tenant Ecommerce Platform - Complete Project Structure

## Project Overview

This document outlines the complete project structure for a production-ready multi-tenant ecommerce platform with marketplace integration. The platform implements complete vendor isolation with comprehensive business features including notifications, media management, search, caching, audit logging, and monitoring.

## Technology Stack

- **Backend**: Python FastAPI with PostgreSQL
- **Frontend**: Vanilla HTML, CSS, JavaScript with AJAX
- **Background Jobs**: Celery with Redis
- **Search**: Elasticsearch with database fallback
- **Caching**: Redis multi-layer caching
- **Storage**: Local/S3 with CDN integration
- **Monitoring**: Custom monitoring with alerting
- **Deployment**: Docker with environment-based configuration

## Complete Directory Structure

```
├── main.py                     # FastAPI application entry point
├── app/
│   ├── api/
│   │   ├── deps.py             # Common dependencies
│   │   ├── main.py             # API router setup
│   │   └── v1/                 # API version 1 routes
│   │       ├── admin/          # Super admin endpoints
│   │       │   ├── __init__.py
│   │       │   ├── auth.py     # Admin authentication
│   │       │   ├── vendors.py  # Vendor management (CRUD, bulk import)
│   │       │   ├── dashboard.py # Admin dashboard & statistics
│   │       │   ├── users.py    # User management across vendors
│   │       │   ├── marketplace.py # System-wide marketplace monitoring
│   │       │   └── monitoring.py # Platform monitoring & alerts
│   │       ├── vendor/         # Vendor-scoped endpoints
│   │       │   ├── __init__.py
│   │       │   ├── auth.py     # Vendor team authentication
│   │       │   ├── dashboard.py # Vendor dashboard & statistics
│   │       │   ├── products.py # Vendor catalog management (Product table)
│   │       │   ├── marketplace.py # Marketplace import & selection (MarketplaceProduct table)
│   │       │   ├── orders.py   # Vendor order management
│   │       │   ├── customers.py # Vendor customer management
│   │       │   ├── teams.py    # Team member management
│   │       │   ├── inventory.py # Inventory operations (vendor catalog products)
│   │       │   ├── payments.py # Payment configuration & processing
│   │       │   ├── media.py    # File and media management
│   │       │   ├── notifications.py # Notification management
│   │       │   └── settings.py # Vendor settings & configuration
│   │       ├── public/         # Public customer-facing endpoints
│   │       │   ├── __init__.py
│   │       │   └── vendors/    # Vendor-specific public APIs
│   │       │       ├── shop.py     # Public shop info
│   │       │       ├── products.py # Public product catalog (Product table only)
│   │       │       ├── search.py   # Product search functionality
│   │       │       ├── cart.py     # Shopping cart operations
│   │       │       ├── orders.py   # Order placement
│   │       │       ├── payments.py # Payment processing
│   │       │       └── auth.py     # Customer authentication
│   │       └── shared/         # Shared/utility endpoints
│   │           ├── health.py   # Health checks
│   │           ├── webhooks.py # External webhooks (Stripe, etc.)
│   │           └── uploads.py  # File upload handling
│   ├── core/
│   │   ├── config.py           # Configuration settings
│   │   ├── database.py         # Database setup
│   │   └── lifespan.py         # App lifecycle management
│   ├── exceptions/             # Custom exception handling
│   │   ├── __init__.py         # All exception exports
│   │   ├── base.py             # Base exception classes
│   │   ├── handler.py          # Unified FastAPI exception handlers
│   │   ├── auth.py             # Authentication/authorization exceptions
│   │   ├── admin.py            # Admin operation exceptions
│   │   ├── marketplace.py      # Import/marketplace exceptions
│   │   ├── marketplace_product.py # Marketplace staging exceptions
│   │   ├── product.py          # Vendor catalog exceptions
│   │   ├── vendor.py           # Vendor management exceptions
│   │   ├── customer.py         # Customer management exceptions
│   │   ├── order.py            # Order management exceptions
│   │   ├── payment.py          # Payment processing exceptions
│   │   ├── inventory.py        # Inventory management exceptions
│   │   ├── media.py            # Media/file management exceptions
│   │   ├── notification.py     # Notification exceptions
│   │   ├── search.py           # Search exceptions
│   │   ├── monitoring.py       # Monitoring exceptions
│   │   └── backup.py           # Backup/recovery exceptions
│   └── services/               # Business logic layer
│       ├── auth_service.py     # Authentication/authorization services
│       ├── admin_service.py    # Admin services
│       ├── vendor_service.py   # Vendor management services
│       ├── customer_service.py # Customer services (vendor-scoped)
│       ├── team_service.py     # Team management services
│       ├── marketplace_service.py # Marketplace import services (MarketplaceProduct)
│       ├── marketplace_product_service.py # Marketplace staging services
│       ├── product_service.py  # Vendor catalog services (Product)
│       ├── order_service.py    # Order services (vendor-scoped)
│       ├── payment_service.py  # Payment processing services
│       ├── inventory_service.py # Inventory services (vendor catalog)
│       ├── media_service.py    # File and media management services
│       ├── notification_service.py # Email/notification services
│       ├── search_service.py   # Search and indexing services
│       ├── cache_service.py    # Caching services
│       ├── audit_service.py    # Audit logging services
│       ├── monitoring_service.py # Application monitoring services
│       ├── backup_service.py   # Backup and recovery services
│       ├── configuration_service.py # Configuration management services
│       └── stats_service.py    # Statistics services (vendor-aware)
├── tasks/                      # Background task processing
│   ├── __init__.py
│   ├── task_manager.py         # Celery configuration and task management
│   ├── marketplace_import.py   # Marketplace CSV import tasks
│   ├── email_tasks.py          # Email sending tasks
│   ├── media_processing.py     # Image processing and optimization tasks
│   ├── search_indexing.py      # Search index maintenance tasks
│   ├── analytics_tasks.py      # Analytics and reporting tasks
│   ├── cleanup_tasks.py        # Data cleanup and maintenance tasks
│   └── backup_tasks.py         # Backup and recovery tasks
├── models/
│   ├── database/               # SQLAlchemy ORM models
│   │   ├── __init__.py         # Import all models for easy access
│   │   ├── base.py             # Base model class and common mixins
│   │   ├── user.py             # User model (with vendor relationships)
│   │   ├── vendor.py           # Vendor, VendorUser, Role models
│   │   ├── customer.py         # Customer, CustomerAddress models (vendor-scoped)
│   │   ├── marketplace_product.py # MarketplaceProduct model (staging data)
│   │   ├── product.py          # Product model (vendor catalog)
│   │   ├── order.py            # Order, OrderItem models (vendor-scoped)
│   │   ├── payment.py          # Payment, PaymentMethod, VendorPaymentConfig models
│   │   ├── inventory.py        # Inventory, InventoryMovement models (catalog products)
│   │   ├── marketplace.py      # MarketplaceImportJob model
│   │   ├── media.py            # MediaFile, ProductMedia models
│   │   ├── notification.py     # NotificationTemplate, NotificationQueue, NotificationLog models
│   │   ├── search.py           # SearchIndex, SearchQuery models
│   │   ├── audit.py            # AuditLog, DataExportLog models
│   │   ├── monitoring.py       # PerformanceMetric, ErrorLog, SystemAlert models
│   │   ├── backup.py           # BackupLog, RestoreLog models
│   │   ├── configuration.py    # PlatformConfig, VendorConfig, FeatureFlag models
│   │   ├── task.py             # TaskLog model
│   │   └── admin.py            # Admin-specific models
│   └── schema/                 # Pydantic models for API validation
│       ├── __init__.py         # Common imports
│       ├── base.py             # Base Pydantic models
│       ├── auth.py             # Login, Token, User response models
│       ├── vendor.py           # Vendor management models
│       ├── customer.py         # Customer request/response models
│       ├── team.py             # Team management models
│       ├── marketplace_product.py # Marketplace staging models
│       ├── product.py          # Vendor catalog models
│       ├── order.py            # Order models (vendor-scoped)
│       ├── payment.py          # Payment models
│       ├── inventory.py        # Inventory operation models
│       ├── marketplace.py      # Marketplace import job models
│       ├── media.py            # Media/file management models
│       ├── notification.py     # Notification models
│       ├── search.py           # Search models
│       ├── monitoring.py       # Monitoring models
│       ├── admin.py            # Admin operation models
│       └── stats.py            # Statistics response models
├── middleware/
│   ├── auth.py                 # JWT authentication
│   ├── vendor_context.py       # Vendor context detection and injection
│   ├── rate_limiter.py         # Rate limiting
│   ├── logging_middleware.py   # Request logging
│   └── decorators.py           # Cross-cutting concern decorators
├── storage/                    # Storage backends
│   ├── __init__.py
│   ├── backends.py             # Storage backend implementations
│   └── utils.py                # Storage utilities
├── static/                     # Frontend assets
│   ├── admin/                  # Super admin interface
│   │   ├── login.html          # Admin login page
│   │   ├── dashboard.html      # Admin dashboard
│   │   ├── vendors.html        # Vendor management
│   │   ├── users.html          # User management
│   │   ├── marketplace.html    # System-wide marketplace monitoring
│   │   └── monitoring.html     # System monitoring
│   ├── vendor/                 # Vendor admin interface
│   │   ├── login.html          # Vendor team login
│   │   ├── dashboard.html      # Vendor dashboard
│   │   └── admin/              # Vendor admin pages
│   │       ├── products.html   # Catalog management (Product table)
│   │       ├── marketplace/    # Marketplace integration
│   │       │   ├── imports.html    # Import jobs & history
│   │       │   ├── browse.html     # Browse marketplace products (staging)
│   │       │   ├── selected.html   # Selected products (pre-publish)
│   │       │   └── config.html     # Marketplace configuration
│   │       ├── orders.html     # Order management
│   │       ├── customers.html  # Customer management
│   │       ├── teams.html      # Team management
│   │       ├── inventory.html  # Inventory management (catalog products)
│   │       ├── payments.html   # Payment configuration
│   │       ├── media.html      # Media library
│   │       ├── notifications.html # Notification templates & logs
│   │       └── settings.html   # Vendor settings
│   ├── shop/                   # Customer-facing shop interface
│   │   ├── home.html           # Shop homepage
│   │   ├── products.html       # Product catalog (Product table only)
│   │   ├── product.html        # Product detail page
│   │   ├── search.html         # Search results page
│   │   ├── cart.html           # Shopping cart
│   │   ├── checkout.html       # Checkout process
│   │   └── account/            # Customer account pages
│   │       ├── login.html      # Customer login
│   │       ├── register.html   # Customer registration
│   │       ├── profile.html    # Customer profile
│   │       ├── orders.html     # Order history
│   │       └── addresses.html  # Address management
│   ├── css/
│   │   ├── admin/              # Admin interface styles
│   │   ├── vendor/             # Vendor interface styles
│   │   ├── shop/               # Customer shop styles
│   │   ├── shared/             # Common styles
│   │   └── themes/             # Vendor-specific themes
│   └── js/
│       ├── shared/             # Common JavaScript utilities
│       │   ├── vendor-context.js # Vendor context detection & management
│       │   ├── api-client.js   # API communication utilities
│       │   ├── notification.js # Notification handling
│       │   ├── media-upload.js # File upload utilities
│       │   └── search.js       # Search functionality
│       ├── admin/              # Admin interface scripts
│       │   ├── dashboard.js    # Admin dashboard
│       │   ├── vendors.js      # Vendor management
│       │   ├── monitoring.js   # System monitoring
│       │   └── analytics.js    # Admin analytics
│       ├── vendor/             # Vendor interface scripts
│       │   ├── products.js     # Catalog management
│       │   ├── marketplace.js  # Marketplace integration
│       │   ├── orders.js       # Order management
│       │   ├── payments.js     # Payment configuration
│       │   ├── media.js        # Media management
│       │   └── dashboard.js    # Vendor dashboard
│       └── shop/               # Customer shop scripts
│           ├── catalog.js      # Product browsing
│           ├── search.js       # Product search
│           ├── cart.js         # Shopping cart
│           ├── checkout.js     # Checkout process
│           └── account.js      # Customer account
├── tests/                      # Comprehensive test suite
│   ├── unit/                   # Unit tests
│   │   ├── services/           # Service layer tests
│   │   │   ├── test_marketplace_service.py # Marketplace staging tests
│   │   │   ├── test_product_service.py     # Catalog management tests
│   │   │   ├── test_payment_service.py     # Payment processing tests
│   │   │   ├── test_notification_service.py # Notification tests
│   │   │   ├── test_search_service.py      # Search functionality tests
│   │   │   ├── test_media_service.py       # Media management tests
│   │   │   └── test_cache_service.py       # Caching tests
│   │   ├── models/             # Model tests
│   │   │   ├── test_marketplace_product.py # Staging model tests
│   │   │   ├── test_product.py             # Catalog model tests
│   │   │   ├── test_payment.py             # Payment model tests
│   │   │   └── test_vendor.py              # Vendor model tests
│   │   └── api/                # API endpoint tests
│   │       ├── test_admin_api.py           # Admin API tests
│   │       ├── test_vendor_api.py          # Vendor API tests
│   │       └── test_public_api.py          # Public API tests
│   ├── integration/            # Integration tests
│   │   ├── test_marketplace_workflow.py   # End-to-end import workflow
│   │   ├── test_order_workflow.py         # Complete order process
│   │   ├── test_payment_workflow.py       # Payment processing
│   │   └── test_notification_workflow.py  # Notification sending
│   ├── e2e/                    # End-to-end tests
│   │   ├── test_vendor_onboarding.py      # Complete vendor setup
│   │   ├── test_customer_journey.py       # Customer shopping experience
│   │   └── test_admin_operations.py       # Admin platform management
│   └── fixtures/               # Test data fixtures
│       ├── marketplace_data.py # Sample marketplace import data
│       ├── catalog_data.py     # Sample vendor catalog data
│       ├── order_data.py       # Sample order data
│       └── user_data.py        # Sample user and vendor data
├── scripts/                    # Utility scripts
│   ├── init_db.py             # Database initialization
│   ├── create_admin.py        # Create initial admin user
│   ├── backup_database.py     # Manual backup script
│   ├── seed_data.py           # Development data seeding
│   └── migrate_data.py        # Data migration utilities
├── docker/                     # Docker configuration
│   ├── Dockerfile             # Application container
│   ├── docker-compose.yml     # Development environment
│   ├── docker-compose.prod.yml # Production environment
│   └── nginx.conf             # Nginx configuration
├── docs/                       # Documentation
│   ├── api/                   # API documentation
│   ├── deployment/            # Deployment guides
│   ├── development/           # Development setup
│   └── user_guides/           # User manuals
├── .env.example               # Environment variables template
├── requirements.txt           # Python dependencies
├── requirements-dev.txt       # Development dependencies
├── README.md                  # Project documentation
└── DEPLOYMENT.md             # Deployment instructions
```

## Architecture Principles

### Multi-Tenancy Model
- **Complete Vendor Isolation**: Each vendor operates independently with no data sharing
- **Chinese Wall**: Strict separation between vendor data and operations
- **Self-Service**: Vendors manage their own teams, products, and marketplace integrations
- **Scalable**: Single codebase serves all vendors with vendor-specific customization

### Data Flow Architecture
```
Marketplace CSV → MarketplaceProduct (staging) → Product (catalog) → Order → Analytics
                                 ↓
                          Email Notifications → Audit Logs → Monitoring
```

### API Structure
- **Admin APIs** (`/api/v1/admin/`): Platform-level administration
- **Vendor APIs** (`/api/v1/vendor/`): Vendor-scoped operations (requires vendor context)
- **Public APIs** (`/api/v1/public/vendors/{vendor_id}/`): Customer-facing operations
- **Shared APIs** (`/api/v1/shared/`): Utility endpoints (health, webhooks)

### Service Layer Architecture
- **Domain Services**: Each service handles one business domain (products, orders, payments)
- **Cross-Cutting Services**: Shared services (cache, audit, monitoring, notifications)
- **Integration Services**: External service integration (payments, search, storage)

### Frontend Architecture
- **Static Assets**: All frontend files served from `/static/` directory
- **Single Application**: One frontend codebase serving all vendors
- **Context-Aware Routing**: Automatic vendor detection via subdomain or path
- **Dynamic Theming**: Vendor-specific customization and branding
- **Role-Based UI**: Permission-driven interface elements

## Key Features

### Core Business Features
- Multi-vendor marketplace with complete isolation
- Marketplace product import and curation workflow
- Comprehensive order and payment processing
- Customer management with vendor-scoped accounts
- Team management with role-based permissions
- Inventory tracking and management

### Advanced Features
- Email notification system with vendor branding
- File and media management with CDN integration
- Advanced search with Elasticsearch
- Multi-layer caching for performance
- Comprehensive audit logging for compliance
- Real-time monitoring and alerting
- Automated backup and disaster recovery
- Configuration management with feature flags

### Security Features
- JWT-based authentication with vendor context
- Role-based access control with granular permissions
- Complete vendor data isolation at all layers
- Audit trails for all operations
- Secure file storage with access controls
- Rate limiting and abuse prevention

### Integration Capabilities
- Stripe Connect for multi-vendor payments
- Marketplace integrations (Letzshop with extensible framework)
- Multiple storage backends (Local, S3, GCS)
- Search engines (Elasticsearch with database fallback)
- Email providers (SendGrid, SMTP)
- Monitoring and alerting systems

## Deployment Modes

### Development Mode
- **Path-based routing**: `localhost:3000/vendor/vendorname/`
- **Admin access**: `localhost:3000/admin/`
- **Easy context switching**: Clear vendor separation in URLs
- **Local storage**: Files stored locally with hot reload

### Production Mode
- **Subdomain routing**: `vendorname.platform.com`
- **Admin subdomain**: `admin.platform.com`
- **Custom domains**: `customdomain.com` (enterprise feature)
- **CDN integration**: Optimized asset delivery
- **Distributed caching**: Redis cluster for performance
- **Automated backups**: Scheduled database and file backups

## Technology Integration

### Database Layer
- **PostgreSQL**: Primary database with ACID compliance
- **Redis**: Caching and session storage
- **Elasticsearch**: Search and analytics (optional)

### Background Processing
- **Celery**: Distributed task processing
- **Redis**: Message broker and result backend
- **Monitoring**: Task progress and error tracking

### External Services
- **Stripe Connect**: Payment processing
- **SendGrid/SMTP**: Email delivery
- **AWS S3/GCS**: Cloud storage
- **CloudFront/CloudFlare**: CDN

### Monitoring Stack
- **Custom Monitoring**: Application-specific metrics
- **Error Tracking**: Comprehensive error logging
- **Performance Monitoring**: Response times and throughput
- **Health Checks**: Automated system health monitoring

This structure provides a robust foundation for a scalable, multi-tenant ecommerce platform with enterprise-grade features while maintaining clean separation of concerns and supporting multiple deployment modes.