From 85bd4896b9064e1e5434653e53855a9508894d26 Mon Sep 17 00:00:00 2001
From: vaseksmolik <66821604+vaseksmolik@users.noreply.github.com>
Date: Wed, 31 Aug 2022 10:21:18 +0200
Subject: [PATCH] PrimaryKeyRelatedField with defined pk_field didn't work

It tries to find "pk_field" on self, which is field class. I changed it to use getattr method on value instead. Used in PrimaryKeyRelatedField.to_representation() and PrimaryKeyRelatedField.to_internal_value()
---
 rest_framework/relations.py | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index bdedd43b8..cb8617fb8 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -255,23 +255,24 @@ class PrimaryKeyRelatedField(RelatedField):
         return True
 
     def to_internal_value(self, data):
+        pk = "pk"
         if self.pk_field is not None:
-            data = self.pk_field.to_internal_value(data)
+            pk = self.pk_field         
         queryset = self.get_queryset()
         try:
             if isinstance(data, bool):
                 raise TypeError
-            return queryset.get(pk=data)
+            return queryset.get(**{pk: data})
         except ObjectDoesNotExist:
             self.fail('does_not_exist', pk_value=data)
         except (TypeError, ValueError):
             self.fail('incorrect_type', data_type=type(data).__name__)
 
     def to_representation(self, value):
+        pk = "pk"
         if self.pk_field is not None:
-            return self.pk_field.to_representation(value.pk)
-        return value.pk
-
+            pk = self.pk_field
+        return getattr(value, pk)
 
 class HyperlinkedRelatedField(RelatedField):
     lookup_field = 'pk'