E-Invoice Viewer

This project provides a comprehensive solution for viewing invoices XRechnung XML format. It includes both a Python script for standalone PDF generation and a Business Central AL extension for integrated invoice viewing.

Features

Python Script (xml_to_invoice_pdf.py)

• Parses XML invoice files
• Generates PDF invoices with detailed formatting
• Supports comprehensive invoice data extraction including:
  • Header information (ID, dates, currency, buyer reference, notes, type code)
  • Supplier and customer details
  • Contact information (name, phone, email)
  • Payment information (means code, account, terms)
  • Invoice line items with quantities, prices, discounts
  • Tax subtotals and totals
  • Legal monetary totals

Business Central AL Extension

• Report: EInvoiceViewer.Report.al - Main report for displaying parsed invoice data
• Layout: Viewer.rdlc - RDLC report layout with comprehensive fields
• Integration: Automatic XML parsing and data population into Business Central
• Page Extensions: Integration with Incoming Documents for seamless workflow

Installation

Python Requirements

pip install reportlab

Business Central Extension

1. Import the AL extension files into your Business Central development environment
2. Publish and install the extension
3. The report will be available under Reports and Analysis

See how the business central integration works:

Usage

See how a xml invoice could look like:

Python Script

python xml_to_invoice_pdf.py input_invoice.xml output_invoice.pdf

Example:

python xml_to_invoice_pdf.py 01.01a-INVOICE_ubl.xml invoice.pdf

Business Central Report

1. Navigate to the E-Invoice Viewer report
2. Select an XML file when prompted
3. The report will automatically parse and display the invoice data

Use incoming documents to validate the xrechnung xml file:

After loading the xml file, our extension generates the pdf file for better visualization:

And now the preview of the pdf file in Business Central:

XML Structure Support

The solution supports the following invoice elements:

Header Elements

• cbc:ID - Invoice number
• cbc:IssueDate - Issue date
• cbc:DocumentCurrencyCode - Currency
• cbc:BuyerReference - Buyer reference
• cbc:Note - Invoice notes
• cbc:InvoiceTypeCode - Invoice type

Party Information

• Supplier details (name, address, contact)
• Customer details (name, address)
• Contact information (name, phone, email)

Payment Information

• Payment means code
• Payee financial account
• Payment terms

Line Items

• Line ID and description
• Quantity and unit price
• Line amount and discounts
• Tax category and percentage
• Additional line notes and references

Tax and Totals

• Tax subtotals by category
• Legal monetary totals (line extension, tax exclusive/inclusive amounts)
• Payable amount

Architecture

Python Component

• Uses xml.etree.ElementTree for XML parsing
• reportlab library for PDF generation
• Namespace-aware XPath queries for reliable data extraction
• Comprehensive error handling and data validation

AL Extension Component

• XML parsing using Business Central's XmlDocument and XmlNamespaceManager
• Data population into temporary Sales Header and Line tables
• RDLC layout for professional report presentation
• Integration with Incoming Documents workflow

File Structure

app/
├── xml_to_invoice_pdf.py          # Python PDF generation script
├── src/
│   ├── EInvoiceViewer.Report.al   # Main AL report
│   ├── Viewer.rdlc                # Report layout
│   └── PTEAfterImportIntoDoc.Codeunit.al  # Integration codeunit
├── 01.01a-INVOICE_ubl.xml         # Sample XML file
└── README.md                      # This file

Contributing

This project is based on the AL-Go Per Tenant Extension Template. Please refer to the AL-Go documentation for contribution guidelines.

License

This project is provided as-is for educational and development purposes.