forked from enviPath/enviPy
21 lines
695 B
Python
21 lines
695 B
Python
from django.db import transaction
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from django.db.models.signals import pre_delete
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from django.dispatch import receiver
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from epdb.models import Node, Edge
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@receiver(pre_delete, sender=Node)
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@transaction.atomic
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def delete_orphan_edges(sender, instance, **kwargs):
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# check if the node that is about to be deleted is the only start node
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for edge in Edge.objects.filter(start_nodes=instance):
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if edge.start_nodes.count() == 1:
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edge.delete()
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# same for end_nodes
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for edge in Edge.objects.filter(end_nodes=instance):
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# check if the node that is about to be deleted is the only start node
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if edge.end_nodes.count() == 1:
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edge.delete()
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