diff --git a/AKScheduling/models.py b/AKScheduling/models.py index bfdb1e16d54a844501082704704239f34d62d429..cabf78e16e38fd5e14b4383958244596fc935ddd 100644 --- a/AKScheduling/models.py +++ b/AKScheduling/models.py @@ -1,4 +1,4 @@ -from django.db.models.signals import post_save, m2m_changed +from django.db.models.signals import post_save, m2m_changed, pre_delete from django.dispatch import receiver from django.utils.translation import gettext_lazy as _ @@ -551,6 +551,19 @@ def akslot_changed_handler(sender, instance: AKSlot, **kwargs): update_constraint_violations(new_violations, existing_violations_to_check) +@receiver(pre_delete, sender=AKSlot) +def akslot_deleted_handler(sender, instance: AKSlot, **kwargs): + # Manually clean up or remove constraint violations that belong to this slot since there is no cascade deletion + # for many2many relationships. Explicitly listening for AK deletion signals is not necessary since they will + # transitively trigger this signal and we always set both AK and AKSlot references in a constraint violation + print(f"{instance} deleted") + + for cv in instance.constraintviolation_set.all(): + # Make sure not delete CVs that e.g., show three parallel slots in a single room + if cv.ak_slots.count() <= 2: + cv.delete() + + @receiver(post_save, sender=Room) def room_changed_handler(sender, instance: Room, **kwargs): # Changes might affect: Room size