Implement nearly-stock DRF create() and update() functionality for synthetic CustomObjectSerializer

Author: bctiemann

netbox_custom_objects/api/serializers.py

@@ -8,6 +8,7 @@
 from rest_framework import serializers
 from rest_framework.exceptions import ValidationError
 from rest_framework.reverse import reverse
+from rest_framework.utils import model_meta
 
 from netbox_custom_objects import field_types
 from netbox_custom_objects.models import (CustomObject, CustomObjectType,
@@ -253,6 +254,44 @@ def get_display(self, obj):
         """Get display representation of the object"""
         return str(obj)
 
+    # Stock DRF create() without raise_errors_on_nested_writes guard
+    def create(self, validated_data):
+        ModelClass = self.Meta.model
+
+        info = model_meta.get_field_info(ModelClass)
+        many_to_many = {}
+        for field_name, relation_info in info.relations.items():
+            if relation_info.to_many and (field_name in validated_data):
+                many_to_many[field_name] = validated_data.pop(field_name)
+
+        instance = ModelClass._default_manager.create(**validated_data)
+
+        if many_to_many:
+            for field_name, value in many_to_many.items():
+                field = getattr(instance, field_name)
+                field.set(value)
+
+        return instance
+
+    # Stock DRF update() with custom field.set() for M2M
+    def update(self, instance, validated_data):
+        info = model_meta.get_field_info(instance)
+
+        m2m_fields = []
+        for attr, value in validated_data.items():
+            if attr in info.relations and info.relations[attr].to_many:
+                m2m_fields.append((attr, value))
+            else:
+                setattr(instance, attr, value)
+
+        instance.save()
+
+        for attr, value in m2m_fields:
+            field = getattr(instance, attr)
+            field.set(value, clear=True)
+
+        return instance
+
     # Create basic attributes for the serializer
     attrs = {
         "Meta": meta,
@@ -261,6 +300,8 @@ def get_display(self, obj):
         "get_url": get_url,
         "display": serializers.SerializerMethodField(),
         "get_display": get_display,
+        "create": create,
+        "update": update,
     }
 
     for field in model_fields: