Export Functionality: Multiple Exporters Failing

Problem Description

Following the fix for issue #1250 (HTTP 500 error preventing export page from loading), systematic testing reveals that approximately 7 out of 19 export options fail with "An unexpected error has occurred, please try again later" when attempting to generate exports.

The fix in PR #1258 successfully resolved the page load issue and form validation problems, but underlying issues within individual exporter implementations remain.

Current Status

Working Exporters (12 confirmed)

• All invoices
• Answers to file upload questions
• Check-in log (all successful scans)
• Email addresses (text file)
• Gift card redemptions
• Invoice data
• List of orders with taxes
• List of orders with taxes (PDF)
• Order overview (PDF)
• Order payments and refunds
• Quota availabilities
• Waiting list

Failing Exporters (7 confirmed)

All display error message: "An unexpected error has occurred, please try again later"

• All PDF tickets in one file
• Attendee badges
• Check-in list
• Check-in list (PDF)
• Order data
• Order data (JSON)
• dekodi NREI (JSON)

Technical Details

Error Symptoms

• Export page loads successfully
• Forms render correctly
• Submission returns generic error message
• No specific error details shown to user
• HTTP 200 status returned (not 500)

Observed Log Patterns

Docker logs show lxml.etree errors for some exporters:

lxml.etree.LxmlSyntaxError: inconsistent exit action in context manager
lxml.etree.LxmlSyntaxError: not in an element

These errors appear related to Excel/XML generation in openpyxl library interactions.

Previously Fixed Issues

Issue 1: Event.items vs Event.products

• File: app/eventyay/plugins/checkinlists/exporters.py
• Problem: Referenced non-existent Event.items relation
• Solution: Changed to Event.products
• Status: Fixed in PR fix: unable to export order data – HTTP 500 error #1258

Issue 2: Missing JSON_FIELD_AVAILABLE Setting

• Problem: Setting undefined in settings.py
• Solution: Added based on database backend detection
• Status: Fixed in PR fix: unable to export order data – HTTP 500 error #1258

Issue 3: Form Validation Logic

• Files: control/views/orders.py, control/views/organizer.py
• Problem: Unsafe cleaned_data access
• Solution: Safe access using getattr()
• Status: Fixed in PR fix: unable to export order data – HTTP 500 error #1258

Testing Methodology

Testing performed at /control/event/{organizer}/{event}/orders/export/

For each exporter:

1. Navigate to export page
2. Select exporter from list
3. Fill required fields (if any)
4. Click generate/export button
5. Document success or failure with error message

Related Work

• Original issue: Ticket Component: Unable to Export Order Data – HTTP 500 Error #1250 - Unable to Export Order Data – HTTP 500 Error
• Fix PR: fix: unable to export order data – HTTP 500 error #1258 - Fixed page load and form validation
• Related models: Event, Product, Order, OrderPosition