From b79099f7baf104336bfe7fff7a8c57bc451a8d96 Mon Sep 17 00:00:00 2001
From: kanazawa <55349166+wnd-ft@users.noreply.github.com>
Date: Sun, 11 Dec 2022 01:48:43 +0900
Subject: [PATCH] Use PrimaryKeyRelatedField pkfield in openapi (#8315)

---
 rest_framework/schemas/openapi.py |  2 ++
 tests/schemas/test_openapi.py     | 17 +++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/rest_framework/schemas/openapi.py b/rest_framework/schemas/openapi.py
index 840f6977e..ea220c631 100644
--- a/rest_framework/schemas/openapi.py
+++ b/rest_framework/schemas/openapi.py
@@ -387,6 +387,8 @@ class AutoSchema(ViewInspector):
                 'items': self.map_field(field.child_relation)
             }
         if isinstance(field, serializers.PrimaryKeyRelatedField):
+            if getattr(field, "pk_field", False):
+                return self.map_field(field=field.pk_field)
             model = getattr(field.queryset, 'model', None)
             if model is not None:
                 model_field = model._meta.pk
diff --git a/tests/schemas/test_openapi.py b/tests/schemas/test_openapi.py
index e39c9df47..0ea6d1ff9 100644
--- a/tests/schemas/test_openapi.py
+++ b/tests/schemas/test_openapi.py
@@ -19,6 +19,7 @@ from rest_framework.renderers import (
 from rest_framework.request import Request
 from rest_framework.schemas.openapi import AutoSchema, SchemaGenerator
 
+from ..models import BasicModel
 from . import views
 
 
@@ -144,6 +145,22 @@ class TestFieldMapping(TestCase):
         assert data['properties']['ro_field']['nullable'], "ro_field nullable must be true"
         assert data['properties']['ro_field']['readOnly'], "ro_field read_only must be true"
 
+    def test_primary_key_related_field(self):
+        class PrimaryKeyRelatedFieldSerializer(serializers.Serializer):
+            basic = serializers.PrimaryKeyRelatedField(queryset=BasicModel.objects.all())
+            uuid = serializers.PrimaryKeyRelatedField(queryset=BasicModel.objects.all(),
+                                                      pk_field=serializers.UUIDField())
+            char = serializers.PrimaryKeyRelatedField(queryset=BasicModel.objects.all(),
+                                                      pk_field=serializers.CharField())
+
+        serializer = PrimaryKeyRelatedFieldSerializer()
+        inspector = AutoSchema()
+
+        data = inspector.map_serializer(serializer=serializer)
+        assert data['properties']['basic']['type'] == "integer"
+        assert data['properties']['uuid']['format'] == "uuid"
+        assert data['properties']['char']['type'] == "string"
+
 
 @pytest.mark.skipif(uritemplate is None, reason='uritemplate not installed.')
 class TestOperationIntrospection(TestCase):