Problem:
- Photo upload with empty date parameter (date='')
- PostgreSQL rejects empty string for DATE field
- Error: "invalid input syntax for type date: ''"
- Occurred when saving circumference entry with only photo
Fix:
- Convert empty string to NULL before INSERT
- Check: date if date and date.strip() else None
- NULL is valid for optional date field
Test case:
- Circumference entry with only photo → should work now
- Photo without date → stored with date=NULL ✓
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Create feature_logger.py with JSON logging infrastructure
- Add log_feature_usage() calls to all 9 routers after check_feature_access()
- Logs written to /app/logs/feature-usage.log
- Tracks all usage (not just violations) for future analysis
- Phase 2: Non-blocking monitoring complete
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>