Inventory Management System - Backend API Documentation

Overview

The Inventory Management System (IMS) is a production-ready, enterprise-grade RESTful API built with .NET 9 Web API. It provides comprehensive functionality for managing inventory operations across multiple warehouses with features like real-time stock tracking, order management, and role-based access control.

Key Features

• Product Management: Complete CRUD operations for products with categories and suppliers
• Multi-Warehouse Support: Track inventory across multiple warehouse locations
• Order Processing: Handle sales and purchase orders with automatic stock updates
• User Management: Role-based access control with four permission levels
• Advanced Filtering: Pagination, filtering, sorting, and searching capabilities
• Validation: Robust input validation using FluentValidation
• Documentation: Interactive API documentation with Scalar

Tech Stack

Core Technologies

Component	Technology	Version
Framework	.NET Web API	9.0
ORM	Entity Framework Core	9.0.9
Database	Microsoft SQL Server	2019+

Libraries and Tools

Purpose	Library	Description
Authentication	JWT Bearer	Token-based authentication
Validation	FluentValidation	Request validation
Logging	Serilog	Structured logging
Documentation	Swagger/OpenAPI	API documentation
Documentation UI	Scalar	Modern API documentation interface

---

Project Structure

inventory_management_system/
│
├── Controllers/                    # API Controllers
│   ├── AuthController.cs
│   ├── ProductsController.cs
│   ├── CategoriesController.cs
│   ├── OrdersController.cs
│   └── ...
│
├── Data/                          # Database Context
│   └── ApplicationDBContext.cs
│
├── DTOs/                          # Data Transfer Objects
│   ├── Requests/                 # Request DTOs
│   │   ├── CreateProductRequest.cs
│   │   ├── UpdateProductRequest.cs
│   │   └── ...
│   └── Responses/                # Response DTOs
│       ├── ProductResponse.cs
│       ├── OrderResponse.cs
│       └── ...
│
├── Enums/                         # Enumeration Types
│   ├── OrderStatus.cs
│   ├── OrderType.cs
│   ├── UserRole.cs
│   └── ...
│
├── Exceptions/                    # Custom Exceptions
│   ├── NotFoundException.cs
│   ├── UnauthorizedException.cs
│   └── ...
│
├── Extensions/                    # Extension Methods
│   ├── ServiceExtensions.cs
│   └── JwtExtensions.cs
│
├── Filters/                       # Action Filters
│   └── RolePermissionAttribute.cs
│
├── Helpers/                       # Helper Classes
│   ├── ProblemDetailHelper.cs
│   └── ...
│
├── Middleware/                    # Custom Middleware
│   └── GlobalExceptionMiddleware.cs
│
├── Migrations/                    # EF Core Migrations
│   └── [Timestamp]_InitialCreate.cs
│
├── Models/                        # Domain Entities
│   ├── User.cs
│   ├── Product.cs
│   ├── Category.cs
│   ├── Order.cs
│   ├── OrderItem.cs
│   ├── Inventory.cs
│   ├── Warehouse.cs
│   └── ...
│
├── Repository/                    # Data Access Layer
│   ├── Implementations/
│   │   ├── ProductRepository.cs
│   │   ├── OrderRepository.cs
│   │   └── ...
│   └── Interfaces/
│       ├── IProductRepository.cs
│       ├── IOrderRepository.cs
│       └── ...
│
├── Security/                      # Security Utilities
│   └── PasswordHasher.cs
│
├── Services/                      # Business Logic Layer
│   ├── Implementations/
│   │   ├── AuthService.cs
│   │   ├── ProductService.cs
│   │   ├── OrderService.cs
│   │   └── ...
│   └── Interfaces/
│       ├── IAuthService.cs
│       ├── IProductService.cs
│       ├── IOrderService.cs
│       └── ...
│
├── Validations/                   # FluentValidation Validators
│   ├── CreateProductValidator.cs
│   ├── LoginRequestValidator.cs
│   └── ...
│
├── logs/                          # Application Logs
│   └── log-YYYYMMDD.txt
│
├── appsettings.json              # Configuration
├── appsettings.Development.json  # Development Config
├── appsettings.Production.json   # Production Config
├── Program.cs                    # Application Entry Point
└── inventory_management_system.csproj

---

Getting Started

Prerequisites

Before you begin, ensure you have the following installed:

• .NET 8 SDK or later (Download)
• SQL Server (LocalDB, Express, or Full Edition)
• Visual Studio 2022 / VS Code / JetBrains Rider
• Git (for version control)

Installation

Step 1: Clone the Repository

git clone <repository-url>
cd inventory_management_system

Step 2: Restore Dependencies

dotnet restore

Step 3: Update Configuration

Edit appsettings.json or appsettings.Development.json:

{
  "ConnectionStrings": {
    "DefaultConnection": "Server=.;Database=InventoryDB;Trusted_Connection=True;TrustServerCertificate=True;"
  },
  "Jwt": {
    "Key": "your-super-secret-key-minimum-32-characters-long",
    "Issuer": "InventoryManagementSystem",
    "Audience": "IMSUsers",
    "AccessTokenExpirationMinutes": 15,
    "RefreshTokenExpirationDays": 7
  }
}

Database Setup

Step 1: Create Database Migration

dotnet ef migrations add InitialCreate

Step 2: Apply Migration to Database

dotnet ef database update

Running the Application

Development Mode

dotnet run

Or with watch mode (auto-restart on file changes):

dotnet watch run