Extract Gulf Tax Invoices with Gemini: Google Drive to Sheets (n8n)

Extract Arabic/English Gulf Tax Invoices automatically with Google Drive + Gemini → Google Sheets (n8n)

This n8n workflow watches a Google Drive inbox for new invoice PDFs/images, uses Google Gemini to extract invoice + line-item data, validates and normalizes Arabic dates/numbers, and then records everything into Google Sheets—routing files to Processed or Needs review based on validation flags.

What this workflow does

• Detects new invoices: Triggers when a new file is created in your specified Google Drive inbox folder.
• Extracts invoice data with Gemini: Downloads the file and sends it to Google Gemini to extract invoice fields and line items as a single JSON object.
• Normalizes numbers and dates: Converts Arabic-Indic digits, attempts Hijri (Umm al-Qura) to Gregorian date conversion, and standardizes the extracted values.
• Validates Gulf VAT details: Checks KSA/UAE VAT number formats and verifies totals/VAT calculations and model confidence.
• Updates Google Sheets:
  • Appends one row to the Invoices tab for each normalized invoice.
  • Expands extracted line items into one row per item in the Line items tab.
• Routes files for governance: Moves each original file to Needs review when validation flags issues; otherwise moves it to Processed.

Use cases

• Automating invoice ingestion for KSA/UAE VAT workflows without manual copy/paste.
• Back-office processing where invoices arrive as PDFs/images in a shared Google Drive folder.
• SaaS operations teams needing audit-friendly validation and line-item detail in Google Sheets.

Technical details

• n8n trigger/integrations: Google Drive, Google Sheets, Google Gemini (Google AI Studio API key).
• Workflow logic nodes: if, set, code, sticky note (for orchestration and validation flags).
• Required setup: Configure Google credentials, create Drive folders (inbox, processed, needs review), and ensure your spreadsheet has tabs named Invoices and Line items.