Maintain compatibility with serializer_class overrides

rest_framework_simplejwt/views.py

@@ -13,11 +13,17 @@ class TokenViewBase(generics.GenericAPIView):
     authentication_classes = ()
 
     serializer_class = None
+    _serializer_class = ""
 
     www_authenticate_realm = "api"
 
     def get_serializer_class(self):
-        # Get the serializer from settings
+        """
+        If serializer_class is set, use it directly. Otherwise get the class from settings.
+        """
+
+        if self.serializer_class:
+            return self.serializer_class
         try:
             return import_string(self._serializer_class)
         except ImportError:

tests/test_views.py

@@ -4,6 +4,7 @@
 
 from django.contrib.auth import get_user_model
 from django.utils import timezone
+from rest_framework.test import APIRequestFactory
 
 from rest_framework_simplejwt import serializers
 from rest_framework_simplejwt.settings import api_settings
@@ -13,6 +14,7 @@
     datetime_from_epoch,
     datetime_to_epoch,
 )
+from rest_framework_simplejwt.views import TokenViewBase
 
 from .utils import APIViewTestCase, override_api_settings
 
@@ -431,3 +433,15 @@ def test_it_should_return_401_if_token_is_blacklisted(self):
         del self.view_name
 
         self.assertEqual(res.status_code, 401)
+
+
+class TestCustomTokenView(APIViewTestCase):
+    def test_custom_view_class(self):
+        class CustomTokenView(TokenViewBase):
+            serializer_class = serializers.TokenObtainPairSerializer
+
+        factory = APIRequestFactory()
+        view = CustomTokenView.as_view()
+        request = factory.post("/", {}, format="json")
+        res = view(request)
+        self.assertEqual(res.status_code, 400)