Handle invalid recipient email addresses

server/vbv_lernwelt/notify/services.py

@@ -3,6 +3,8 @@ from __future__ import annotations
 from typing import TYPE_CHECKING
 
 import structlog
+from django.core.exceptions import ValidationError
+from django.core.validators import validate_email
 from django.db.models import Model
 from notifications.signals import notify
 
@@ -281,6 +283,13 @@ class NotificationService:
             template_data=template_data,
         )
         emailed = False
+
+        try:
+            validate_email(recipient.email)
+        except ValidationError:
+            log.info("Recipient email is invalid")
+            return f"{notification_identifier}_invalid_email"
+
         try:
             notification = NotificationService._find_duplicate_notification(
                 recipient=recipient,