Factory Pattern for Invoice Generation

This project demonstrates a .NET implementation of the Factory Pattern to generate invoices in multiple file formats (PDF, TXT, and CSV). It uses QuestPDF to create professional-grade PDF documents and follows the Repository Pattern to ensure clean and maintainable data access.

Features

• Factory Pattern: Simplifies the creation of invoices in various file formats.
• Invoice Generation: Supports generating invoices as PDF, TXT, and CSV files.
• QuestPDF Integration: Produces high-quality and customizable PDF invoices.
• Repository Pattern: Provides a structured and maintainable data access layer.
• Extensible Design: Easily add support for new file formats or invoice types.

Prerequisites

• .NET 6 or higher

Installation

1. Clone the repository:

   git clone https://github.com/MrEshboboyev/FactoryPattern.git

2. Navigate to the project directory:

   cd FactoryPattern

3. Restore dependencies:

   dotnet restore

Usage

Invoice Generation

The application uses the Factory Pattern to generate invoices in different formats. Below is an example of how to generate invoices in endpoint:

var generator = invoiceGeneratorFactory.CreateInvoiceGenerator(format);
var invoiceData = generator.GenerateInvoice(id);
var contentType = generator.GetContentType();

var fileName = $"Invoice_{id}.{format.ToString().ToLower()}";
    
return Results.File(invoiceData, contentType, fileName);

Adding New Formats

To support a new file format:

1. Create a new class implementing the IInvoiceGenerator interface.
2. Add the new file type to the InvoiceFormat enum.
3. Update the InvoiceGeneratorFactory to include the new type.

Example:

public class ExcelInvoiceGenerator : IInvoiceGenerator
{
    public byte[] GenerateInvoice(Guid invoiceId)
    {
        // Logic to generate an Excel invoice
    }
}

Supported File Formats

• PDF: Generated using QuestPDF.
• CSV: Comma-separated structured invoice data.
• TXT: Simple text-based invoice output.

Contributing

Contributions are welcome! Follow these steps:

1. Fork the repository.
2. Create a feature branch: git checkout -b feature-name.
3. Commit your changes: git commit -m "Add feature".
4. Push to the branch: git push origin feature-name.
5. Open a pull request.

License

This project is licensed under the MIT License. See the LICENSE file for more details.

Acknowledgements

• QuestPDF
• Factory Design Pattern
• Repository Pattern

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Happy coding! 🚀