Three Ways to Extract Invoice Data

1. Automatic Processing (Recommended)

   Simply upload a PDF or image to an invoice:

   • Create a new vendor bill (Accounting → Vendors → Bills)
   • Attach an invoice PDF or image
   • Invoice is automatically processed!
     • EDI decoder triggers on attachment upload
     • OCR extracts text from document
     • LLM extracts structured data
     • Invoice fields are populated

2. Manual Processing

   For invoices created before module installation:

   • Open a draft invoice with an attached PDF/image
   • Click "Process with AI" button
   • Form reloads with extracted data

3. OCA Invoice Import Wizard

   When using OCA's invoice import wizard:

   • Go to Accounting → Vendors → Import Vendor Bill
   • Upload PDF invoice
   • If no embedded XML found, LLM extraction is used as fallback
   • Invoice is created with extracted data

What Gets Extracted

The LLM extracts and populates:

• ✅ Vendor name and VAT number
• ✅ Invoice number and reference
• ✅ Invoice date and due date
• ✅ Currency
• ✅ Subtotal, tax, and total amounts
• ✅ Line items with descriptions, quantities, unit prices, and tax rates

OCA Invoice Import Integration

Follows the standard OCA pattern for extending account_invoice_import:

account_invoice_import_llm/
├── __manifest__.py                   # Dependencies and metadata
├── __init__.py                       # Pre-init hook for module rename
├── models/
│   ├── account_invoice_import_ocr.py # AbstractModel: OCR + LLM extraction
│   └── account_move.py               # "Process with AI" button
├── wizard/
│   └── account_invoice_import.py     # OCA fallback_parse_pdf_invoice()
├── data/
│   ├── llm_prompt_invoice_data.xml   # One-shot extraction prompt
│   └── llm_assistant_data.xml        # Assistant configuration
└── views/
    └── account_move_views.xml        # Button view extension

Processing Flows

Flow 1: Automatic Decoder (Odoo Native):

1. User uploads PDF to invoice
   ↓
2. account.move.create_document_from_attachment_decoders()
   ↓
3. _llm_ocr_decoder() checks if PDF is suitable
   ↓
4. Creates draft invoice with journal
   ↓
5. _extract_invoice_data_from_attachment()
   - Creates LLM thread with OCR context
   - Runs one-shot extraction prompt
   - Returns extracted data as JSON
   ↓
6. _populate_invoice_from_data()
   - Populates vendor, dates, amounts
   - Creates invoice lines
   - Processes UBL XML if present
   ↓
7. Decoder returns invoice
   ↓
8. Journal links attachment to invoice

Flow 2: Manual Trigger:

1. User clicks "Process with AI" button
   ↓
2. action_process_with_llm()
   - Validates invoice is draft
   - Finds PDF/image attachment
   ↓
3. _extract_invoice_data_from_attachment()
   - Same extraction as automatic flow
   ↓
4. _populate_invoice_from_data()
   - Populates invoice fields
   ↓
5. Returns action to reload form view
   ↓
6. User sees populated invoice data

Flow 3: OCA Wizard Fallback:

1. User uploads PDF via OCA wizard
   ↓
2. Wizard calls parse_pdf_invoice()
   ↓
3. Checks for embedded XML (UBL, Factur-X)
   - If found: Uses XML parser
   - If not found: Calls fallback_parse_pdf_invoice()
   ↓
4. Our fallback_parse_pdf_invoice()
   - Creates temp invoice for context
   - Extracts data via LLM
   - Converts to OCA's Invoice Pivot Format
   ↓
5. Wizard creates invoice from pivot format
   ↓
6. Wizard automatically links attachment

Key Components

1. OCR Extraction AbstractModel

   File: models/account_invoice_import_ocr.py

   Central extraction logic shared by wizard and manual button:

   • Runs Mistral OCR on file bytes
   • Renders prompt with OCR text context
   • Calls LLM for structured extraction
   • Converts to OCA Invoice Pivot Format

2. One-Shot Extraction Prompt

   File: data/llm_prompt_invoice_data.xml

   Structured prompt that instructs LLM to extract invoice data in JSON format.

3. OCA Wizard Integration

   File: wizard/account_invoice_import.py

   Extends fallback_parse_pdf_invoice() to delegate to OCR AbstractModel.

EDI Decoder Registration

The module registers _llm_ocr_decoder in Odoo's EDI decoder chain:

@api.model
def _get_create_document_from_attachment_decoders(self):
    decoders = super()._get_create_document_from_attachment_decoders()
    return decoders + [self._llm_ocr_decoder]

Decoder priority ensures XML parsers run first, LLM-OCR as fallback.

Error Handling Strategy

• Top-level handlers: Decoder, manual action, OCA wizard
• Intermediate methods: Raise exceptions directly (no hiding)
• User-friendly errors: Clear messages about what failed and why
• Logging: Detailed error info in server logs for debugging

Pre-Init Hook

File: __init__.py

Handles module rename from llm_assistant_account_invoice → account_invoice_import_llm:

1. Updates ir_model_data records from old module name
2. Adopts orphaned records (prevents FK violations)
3. Prevents duplicate key errors on installation

Invoice Extraction Assistant

Location: Settings → LLM → Assistants → Invoice Data Extraction (Automatic)

The assistant is pre-configured with:

• Prompt: One-shot extraction template with detailed instructions
• Model: Any LLM (GPT-4, Claude, Gemini, etc.)
• OCR Tool: Mistral OCR for text extraction
• Dynamic Context: OCR text injected automatically

Customization

To customize extraction behavior:

1. Go to Settings → LLM → Prompts → Invoice Data Extraction (One-Shot)
2. Edit the instructions argument to add/remove fields
3. Update the JSON structure in default_values
4. Modify _convert_llm_data_to_pivot() if adding new fields

Issue: "No PDF or image attachment found"

Solution: Attach a PDF or image file to the invoice before clicking "Process with AI"

Issue: "Failed to extract data"

Possible causes:

• Poor quality scan/image
• Non-standard invoice format
• OCR couldn't extract text

Solution: Check server logs for detailed error. Try with a higher quality scan.

Issue: "Mistral provider not configured"

Solution: Install llm_mistral module and configure Mistral provider with API key

Issue: Duplicate records after module rename

Solution: The pre-init hook should handle this automatically. If issues persist, check ir_model_data for orphaned records.

Authors

• Apexive Solutions LLC

Contributors

• Module development and LLM integration
• OCA invoice import pattern implementation

Maintainers

This module is maintained by Apexive Solutions LLC.