fixed N+1 error on v2/creatures endpoint

Author: calumbell

api_v2/migrations/0027_alter_creatureaction_parent_and_more.py

@@ -0,0 +1,24 @@
+# Generated by Django 5.1.2 on 2025-03-26 10:46
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('api_v2', '0026_delete_searchresult'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='creatureaction',
+            name='parent',
+            field=models.ForeignKey(help_text='The creature to which this action belongs.', on_delete=django.db.models.deletion.CASCADE, related_name='actions', to='api_v2.creature'),
+        ),
+        migrations.AlterField(
+            model_name='creatureactionattack',
+            name='parent',
+            field=models.ForeignKey(help_text='The creature action to which this attack belongs.', on_delete=django.db.models.deletion.CASCADE, related_name='attacks', to='api_v2.creatureaction'),
+        ),
+    ]

api_v2/models/creature.py

@@ -102,7 +102,7 @@ def get_initiative_bonus(self):
 
     def as_text(self):
         text = self.name + '\n'
-        for action in self.creatureaction_set.all():
+        for action in self.actions.all():
             text+='\n' + action.as_text()
 
         return text
@@ -113,12 +113,7 @@ def search_result_extra_fields(self):
             "type": self.type.name,
             "size": self.size.name,   
         }
-
-    @property
-    def creatureset(self):
-        '''Helper method to rename and return creaturesets.'''
-        return self.creaturesets.all()
-
+        
     @property
     def challenge_rating_text(self):
         '''Challenge rating as text string representation of a fraction or integer. '''
@@ -171,19 +166,14 @@ def experience_points(self):
             except:
                 return None
 
-    @property
-    def actions(self):
-        """Returns the set of actions that are related to this creature."""
-        return self.creatureaction_set
-
-
 class CreatureAction(HasName, HasDescription):
     """Describes an action available to a creature."""
     key = key_field()
 
     parent = models.ForeignKey(
         Creature,
         on_delete=models.CASCADE,
+        related_name='actions',
         help_text='The creature to which this action belongs.'
     )
 
@@ -232,16 +222,13 @@ def as_text(self):
 
         return text
 
-    def attacks(self):
-        return self.creatureactionattack_set
-
-
 class CreatureActionAttack(HasName):
     """Describes an attack action used by a creature."""
     key = key_field()
 
     parent = models.ForeignKey(
         CreatureAction,
+        related_name="attacks",
         on_delete=models.CASCADE,
         help_text='The creature action to which this attack belongs.'
     )

api_v2/serializers/creature.py

@@ -32,7 +32,7 @@ def get_distance_unit(self, CreatureActionAttack):
 
 class CreatureActionSerializer(serializers.ModelSerializer):
     key = serializers.ReadOnlyField()
-    attacks = CreatureActionAttackSerializer(many=True)
+    attacks = CreatureActionAttackSerializer(many=True, read_only=True)
     class Meta:
         model = models.CreatureAction
         fields = '__all__'

api_v2/views/creature.py

@@ -66,20 +66,25 @@ class CreatureViewSet(EagerLoadingMixin, viewsets.ReadOnlyModelViewSet):
     serializer_class = serializers.CreatureSerializer
     filterset_class = CreatureFilterSet
 
+    select_related_fields = []
+
     prefetch_related_fields = [
+        'actions',
+        'actions__attacks',
+        'creaturesets',
         'condition_immunities',
-        'creatureaction_set',
         'damage_immunities',
         'damage_resistances',
         'damage_vulnerabilities',
         'document',
-        'document__gamesystem',
         'document__publisher',
+        'document__gamesystem',
         'environments',
         'languages',
         'languages__document',
         'type',
         'size',
+        'size__document',
         'traits',
     ]