InvoicePro - Invoice & Billing Management System

A production-ready .NET 8 web application for managing invoices, clients, products, and payments with Clean Architecture principles.

🚀 Features

Core Functionality

• Client Management: Complete CRUD operations for client information
• Product/Service Management: Manage products and services with inventory tracking
• Invoice Management: Create, edit, send, and track invoices
• Payment Processing: Record payments and track outstanding balances
• Dashboard: Real-time analytics and overview of business metrics
• PDF Generation: Professional invoice and payment receipt generation
• Email Integration: Send invoices via email with PDF attachments

Technical Features

• Clean Architecture: Domain, Application, Infrastructure, and Web layers
• ASP.NET Core 8: Modern web framework with MVC and Web API
• Entity Framework Core: SQLite database with migrations
• MediatR: CQRS pattern implementation
• AutoMapper: Object-to-object mapping
• FluentValidation: Input validation
• Serilog: Structured logging
• Swagger/OpenAPI: API documentation
• Docker Support: Containerized deployment
• Currency Support: Nigerian Naira (₦/NGN) formatting

🏗️ Architecture

InvoicePro/
├── src/
│   ├── InvoicePro.Domain/          # Domain entities and business logic
│   ├── InvoicePro.Application/     # Application services and DTOs
│   ├── InvoicePro.Infrastructure/  # Data access and external services
│   └── InvoicePro.Web/             # Web API and MVC controllers
├── tests/                          # Unit and integration tests
├── docker-compose.yml             # Multi-container deployment
├── Dockerfile                     # Application containerization
└── README.md                      # This file

🛠️ Prerequisites

• .NET 8 SDK
• Docker (optional)
• Git

📦 Installation & Setup

Option 1: Local Development

1. Clone the repository

   git clone https://github.com/yourusername/invoicepro.git
   cd invoicepro

2. Restore dependencies

   dotnet restore

3. Update database

   dotnet ef database update --project src/InvoicePro.Infrastructure --startup-project src/InvoicePro.Web

4. Run the application

   dotnet run --project src/InvoicePro.Web

5. Access the application

   • Web UI: http://localhost:5291
   • API Documentation: http://localhost:5291/api

Option 2: Docker Deployment

1. Clone the repository

   git clone https://github.com/yourusername/invoicepro.git
   cd invoicepro

2. Run with Docker Compose

   docker-compose up -d

3. Access the application

   • Web UI: http://localhost:8080
   • API Documentation: http://localhost:8080/api

🔧 Configuration

Environment Variables

Create appsettings.Development.json for local development:

{
  "ConnectionStrings": {
    "DefaultConnection": "Data Source=invoicepro.db"
  },
  "Email": {
    "SmtpHost": "smtp.gmail.com",
    "SmtpPort": "587",
    "EnableSsl": "true",
    "Username": "your-email@gmail.com",
    "Password": "your-app-password",
    "FromAddress": "noreply@invoicepro.com"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  }
}

Email Configuration

For email functionality, configure SMTP settings:

1. Gmail Setup:

   • Enable 2-factor authentication
   • Generate an app-specific password
   • Use your Gmail address and app password

2. Other SMTP Providers:

   • Update SmtpHost, SmtpPort, and EnableSsl accordingly

📊 Database Schema

The application uses SQLite with the following main entities:

• Clients: Company information and contact details
• Products: Products and services with pricing
• Invoices: Invoice headers with line items
• Payments: Payment records linked to invoices
• InvoiceItems: Individual line items on invoices

🧪 Testing

Run the test suite:

# Run all tests
dotnet test

# Run with coverage
dotnet test --collect:"XPlat Code Coverage"

📚 API Documentation

The API is documented using Swagger/OpenAPI. Access the interactive documentation at:

• Development: http://localhost:5291/api
• Production: https://yourdomain.com/api

Key Endpoints

• GET /api/v1/dashboard - Dashboard data
• GET /api/v1/clients - List all clients
• POST /api/v1/clients - Create new client
• GET /api/v1/invoices - List all invoices
• POST /api/v1/invoices - Create new invoice
• GET /api/v1/payments - List all payments
• POST /api/v1/payments - Record payment

🐳 Docker Deployment

Single Container

# Build image
docker build -t invoicepro .

# Run container
docker run -p 8080:80 invoicepro

Multi-Container (Recommended)

# Start all services
docker-compose up -d

# View logs
docker-compose logs -f

# Stop services
docker-compose down

🚀 Production Deployment

Azure App Service

1. Create App Service

   az webapp create --resource-group myResourceGroup --plan myAppServicePlan --name invoicepro-app --runtime "DOTNET|8.0"

2. Deploy from GitHub

   • Connect your GitHub repository
   • Enable continuous deployment
   • Configure environment variables

AWS Elastic Beanstalk

1. Package application

   dotnet publish -c Release -o ./publish

2. Deploy using EB CLI

   eb init
   eb create production
   eb deploy

Kubernetes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: invoicepro
spec:
  replicas: 3
  selector:
    matchLabels:
      app: invoicepro
  template:
    metadata:
      labels:
        app: invoicepro
    spec:
      containers:
      - name: invoicepro
        image: invoicepro:latest
        ports:
        - containerPort: 80
        env:
        - name: ConnectionStrings__DefaultConnection
          value: "Data Source=/app/data/invoicepro.db"

🔒 Security Features

• Input Validation: FluentValidation for all user inputs
• SQL Injection Protection: Entity Framework parameterized queries
• XSS Protection: ASP.NET Core built-in protections
• CSRF Protection: Anti-forgery tokens
• Secure Headers: Security headers middleware
• Environment-based Configuration: Separate configs for dev/prod

📈 Monitoring & Logging

• Serilog: Structured logging with multiple sinks
• Health Checks: Application health monitoring
• Performance Counters: Built-in ASP.NET Core metrics
• Exception Handling: Global exception middleware

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Development Guidelines

• Follow Clean Architecture principles
• Write unit tests for new features
• Use meaningful commit messages
• Update documentation as needed
• Follow C# coding conventions

📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

🆘 Support

• Documentation: Wiki
• Issues: GitHub Issues
• Discussions: GitHub Discussions

🙏 Acknowledgments

• ASP.NET Core - Web framework
• Entity Framework Core - ORM
• MediatR - Mediator pattern
• AutoMapper - Object mapping
• Serilog - Logging framework
• Bootstrap - CSS framework
• Font Awesome - Icons

📊 Project Status

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InvoicePro - Professional invoice management made simple. 💼✨