Quba Viewer – Electron Desktop Application for Structured E-Invoice Visualization

Development contribution to Quba Viewer, a cross-platform Electron desktop application used to visualize structured electronic invoices (XML, UBL, CII) and hybrid PDF invoices with embedded data such as Factur-X and ZUGFeRD formats.

Overview

This project involved contributing to the development of Quba Viewer, a cross-platform Electron-based desktop application designed for visualizing structured electronic invoices.

The system supports both XML-based invoice formats and hybrid PDF invoices containing embedded structured data, enabling users to inspect, validate, and interpret financial documents in a readable interface.

🧠 System Concept

The application bridges the gap between:

Raw structured invoice data (XML / UBL / CII)
Human-readable visual representation (UI layer)

It allows users to:

Load electronic invoice files
Parse structured financial data
Visualize invoice content in a formatted UI
Inspect embedded metadata inside PDF invoices

🧰 Technology Stack

Desktop Framework: Electron
Runtime: Node.js
Frontend: JavaScript, HTML, CSS
Data Processing: XSLT transformations
PDF Engine: PDF.js
Architecture: IPC (Main ↔ Renderer process communication)

⚙️ Key Contributions

🧾 Invoice Visualization System

Worked on rendering structured invoice data into a human-readable interface, transforming raw XML into visual components.

🔄 Electron Application Logic

Contributed to desktop application structure including:

window lifecycle handling
IPC communication between processes
file loading and parsing workflow

📄 Hybrid Invoice Support

Enabled handling of hybrid invoice formats:

PDF + embedded XML data
Factur-X / ZUGFeRD compatibility
structured invoice extraction and display

⚡ Data Transformation Layer

Worked with XSLT-based transformations to convert raw invoice data into structured UI output.

🏗 Architecture Design

The system follows a desktop data visualization architecture:

File Input Layer → invoice document loading
Parsing Layer → XML / PDF extraction
Transformation Layer → XSLT processing
Electron Renderer → UI visualization
IPC Layer → communication between processes

🚧 Challenges & Solutions

📄 Complex Structured Data Rendering

Invoice formats vary heavily across standards.

Solution: Implemented structured transformation logic to normalize data before rendering.

⚡ Electron Performance Constraints

Large invoice files can slow rendering.

Solution: Optimized parsing pipeline and minimized blocking operations in renderer process.

🔄 Hybrid File Handling (PDF + XML)

Some invoices contain embedded structured data inside PDFs.

Solution: Built extraction logic to detect and separate embedded XML content.

📌 Outcome

The result is a cross-platform desktop application that simplifies the visualization of complex electronic invoice formats, making structured financial data accessible and readable for end users.

💬 Note

This project demonstrates experience in:

Electron desktop application development
Structured data visualization systems
XML / XSLT processing pipelines
PDF + embedded data extraction
IPC-based application architecture

🔗 Project

Website: https://quba-viewer.org/