fixing unique together validator for fields with source

rest_framework/validators.py

@@ -107,6 +107,7 @@ def set_context(self, serializer):
         """
         # Determine the existing instance, if this is an update operation.
         self.instance = getattr(serializer, 'instance', None)
+        self.serializer = serializer
 
     def enforce_required_fields(self, attrs):
         """
@@ -137,7 +138,11 @@ def filter_queryset(self, attrs, queryset):
 
         # Determine the filter keyword arguments and filter the queryset.
         filter_kwargs = {
-            field_name: attrs[field_name]
+            (
+                field_name
+                if field_name == self.serializer.fields[field_name].source
+                else self.serializer.fields[field_name].source
+            ): attrs[field_name]
             for field_name in self.fields
         }
         return qs_filter(queryset, **filter_kwargs)

test_read_only_default/test_read_only_default.py

@@ -0,0 +1,60 @@
+from django.db import models
+from rest_framework import serializers
+from rest_framework.validators import (
+    UniqueTogetherValidator,
+)
+
+from rest_framework import viewsets
+import json
+from rest_framework import mixins
+from rest_framework import generics
+from rest_framework.views import APIView
+from rest_framework.response import Response
+from rest_framework import status
+from django.test import TestCase
+from rest_framework import status
+
+
+class ModelTwo(models.Model):
+    testfieldtwo = models.CharField(max_length=60, primary_key=True)
+
+class ModelOne(models.Model):
+    testfield = models.ForeignKey(ModelTwo, on_delete=models.CASCADE)
+    alias = models.CharField(max_length=60)
+    name = models.CharField(max_length=60)
+
+    class Meta:
+        unique_together = ('testfield', 'name',)
+
+
+class ExampleSerializer(serializers.ModelSerializer):
+    altername = serializers.CharField(source="testfield", default=ModelTwo(testfieldtwo="model 2 default"), read_only=True)
+
+    class Meta:
+        model = ModelOne
+        fields = ('altername' ,'alias', 'name')
+        validators = [
+            UniqueTogetherValidator(
+                queryset=ModelOne.objects.all(),
+                fields=('testfield', 'name')
+            )
+        ]
+
+class ExampleViewSet(mixins.CreateModelMixin,
+                             mixins.UpdateModelMixin,
+                             viewsets.ReadOnlyModelViewSet):
+
+    queryset = ModelOne.objects.all()
+    serializer_class = ExampleSerializer
+
+
+class ExampleTests(TestCase):
+
+    def url(self):
+        return '/example/'
+
+    def test_created_successfully(self):
+        name = 'blab blah'
+        alias = 'ab ab'
+        response = self.client.post(self.url, {'name': name, 'alias': alias})
+        self.assertEqual(response.status_code, status.HTTP_201_CREATED, response.data)

test_read_only_default/urls.py

@@ -0,0 +1,11 @@
+from django.conf.urls import include, url
+from rest_framework import routers
+from test_read_only_default import ExampleViewSet
+
+router = routers.DefaultRouter()
+router.register(r'example', ExampleViewSet)
+
+urlpatterns = [
+    url('', include(router.urls)),
+    url('api-auth/', include('rest_framework.urls', namespace='rest_framework'))
+]