feat(relations): implement duplicate and merge signal receivers

Closes: #1251

apis_core/relations/apps.py

@@ -4,3 +4,6 @@
 class RelationsNgConfig(AppConfig):
  default_auto_field = "django.db.models.AutoField"
  name = "apis_core.relations"
+
+ def ready(self):
+ from . import signals # noqa: F401

apis_core/relations/signals.py

@@ -0,0 +1,36 @@
+import logging
+
+from django.dispatch import receiver
+from django.contrib.contenttypes.models import ContentType
+
+from apis_core.apis_entities.signals import post_merge_with
+from apis_core.apis_metainfo.signals import post_duplicate
+
+from apis_core.relations.models import Relation
+
+logger = logging.getLogger(__name__)
+
+
+@receiver(post_duplicate)
+def copy_relations(sender, instance, duplicate, **kwargs):
+ logger.info(f"Copying relations from {instance!r} to {duplicate!r}")
+ content_type = ContentType.objects.get_for_model(instance)
+ subj_rels = Relation.objects.filter(subj_content_type=content_type, subj_object_id=instance.id).select_subclasses()
+ obj_rels = Relation.objects.filter(obj_content_type=content_type, obj_object_id=instance.id).select_subclasses()
+ for rel in subj_rels:
+ rel.pk = None
+ rel.subj_object_id = duplicate.id
+ rel.save()
+ for rel in obj_rels:
+ rel.pk = None
+ rel.obj_object_id = duplicate.id
+ rel.save()
+
+
+@receiver(post_merge_with)
+def merge_relations(sender, instance, entities, **kwargs):
+ for ent in entities:
+ logger.info(f"Merging relations from {ent!r} into {instance!r}")
+ content_type = ContentType.objects.get_for_model(ent)
+ Relation.objects.filter(subj_content_type=content_type, subj_object_id=ent.id).update(subj_object_id=instance.id)
+ Relation.objects.filter(obj_content_type=content_type, obj_object_id=ent.id).update(obj_object_id=instance.id)