Small Business Inventory Management System

A comprehensive inventory management system built with FastAPI and SQLite, designed for small businesses to track products, manage inventory transactions, suppliers, and categories.

Features

• Product Management: Create, update, view, and delete products with details like SKU, barcode, pricing, and stock levels
• Inventory Transactions: Track inventory movements (purchases, sales, adjustments, returns)
• Supplier Management: Maintain supplier information and track products by supplier
• Category Organization: Organize products into categories
• User Authentication: Secure JWT-based authentication system
• Role-Based Access Control: Regular users and superusers with different permissions
• API Documentation: Auto-generated interactive documentation

Technology Stack

• Backend: FastAPI (Python)
• Database: SQLite with SQLAlchemy ORM
• Authentication: JWT tokens
• Migration System: Alembic
• Validation: Pydantic

Project Structure

.
├── alembic/              # Database migration scripts
├── app/                  # Main application
│   ├── api/              # API endpoints
│   │   ├── deps.py       # Dependencies (auth, db session)
│   │   └── routes/       # API route modules
│   ├── core/             # Core modules (config, security)
│   ├── crud/             # CRUD operations
│   ├── db/               # Database setup and base classes
│   ├── models/           # SQLAlchemy models
│   └── schemas/          # Pydantic schemas for validation
├── storage/              # Storage directories
│   └── db/               # SQLite database location
├── main.py               # Application entry point
├── alembic.ini           # Alembic configuration
└── requirements.txt      # Python dependencies

Environment Variables

The application uses the following environment variables:

Variable	Description	Default
SECRET_KEY	JWT secret key for token generation	"generate_a_secure_secret_key_here"
ADMIN_PASSWORD	Password for initial admin user	"admin"
ACCESS_TOKEN_EXPIRE_MINUTES	JWT token expiration time in minutes	11520 (8 days)

Getting Started

Prerequisites

• Python 3.8 or higher

Installation

1. Clone the repository:

   git clone <repository-url>
   cd smallbusinessinventorymanagementsystem
   

2. Install dependencies:

   pip install -r requirements.txt
   

3. Set up environment variables (recommended):

   export SECRET_KEY="your-secure-secret-key"
   export ADMIN_PASSWORD="your-admin-password"
   

4. Apply database migrations:

   alembic upgrade head
   

5. Initialize the database with initial data (creates admin user):

   python -m app.initial_data
   

6. Start the application:

   uvicorn main:app --host 0.0.0.0 --port 8000 --reload
   

API Documentation

Once the application is running, you can access:

• Interactive API documentation: http://localhost:8000/docs
• Alternative documentation: http://localhost:8000/redoc
• OpenAPI schema: http://localhost:8000/openapi.json

Authentication

The API uses JWT tokens for authentication. To obtain a token:

1. Make a POST request to /api/v1/login/access-token with form data:

   • username: your username
   • password: your password

2. Use the returned access token in the Authorization header for protected endpoints:

   Authorization: Bearer <your-token>
   

Initial User

An admin user is automatically created when running the initial_data script:

• Username: admin
• Password: The value of ADMIN_PASSWORD env variable (default: "admin")
• Email: admin@example.com

API Endpoints

Authentication

• POST /api/v1/login/access-token - Get access token

Users

• GET /api/v1/users/ - List users (admin only)
• POST /api/v1/users/ - Create user (admin only)
• GET /api/v1/users/me - Get current user
• PUT /api/v1/users/me - Update current user
• GET /api/v1/users/{user_id} - Get user by ID
• PUT /api/v1/users/{user_id} - Update user (admin only)
• DELETE /api/v1/users/{user_id} - Delete user (admin only)

Products

• GET /api/v1/products/ - List products
• POST /api/v1/products/ - Create product
• GET /api/v1/products/{product_id} - Get product by ID
• PUT /api/v1/products/{product_id} - Update product
• DELETE /api/v1/products/{product_id} - Delete product
• POST /api/v1/products/{product_id}/adjust - Adjust product quantity

Categories

• GET /api/v1/categories/ - List categories
• POST /api/v1/categories/ - Create category
• GET /api/v1/categories/{category_id} - Get category by ID
• PUT /api/v1/categories/{category_id} - Update category
• DELETE /api/v1/categories/{category_id} - Delete category

Suppliers

• GET /api/v1/suppliers/ - List suppliers
• POST /api/v1/suppliers/ - Create supplier
• GET /api/v1/suppliers/{supplier_id} - Get supplier by ID
• PUT /api/v1/suppliers/{supplier_id} - Update supplier
• DELETE /api/v1/suppliers/{supplier_id} - Delete supplier

Inventory Transactions

• GET /api/v1/inventory/transactions/ - List transactions
• POST /api/v1/inventory/transactions/ - Create transaction
• GET /api/v1/inventory/transactions/{transaction_id} - Get transaction by ID
• DELETE /api/v1/inventory/transactions/{transaction_id} - Delete transaction (admin only)

Health Check

• GET /health - Check system health

License

MIT License