Solution

cinema/serializers.py

@@ -39,11 +39,13 @@ def update(self, instance, validated_data):
             instance.duration
         )
 
-        actors_data = validated_data.pop("actors")
-        genres_data = validated_data.pop("genres")
+        actors_data = validated_data.get("actors")
+        genres_data = validated_data.get("genres")
 
-        instance.actors.set(actors_data)
-        instance.genres.set(genres_data)
+        if actors_data is not None:
+            instance.actors.set(actors_data)
+        if genres_data is not None:
+            instance.genres.set(genres_data)
 
         instance.save()
 

cinema/views.py

@@ -49,6 +49,7 @@ class ActorDetail(
     mixins.RetrieveModelMixin,
     mixins.UpdateModelMixin,
     mixins.DestroyModelMixin,
+    mixins.CreateModelMixin,
     generics.GenericAPIView
 ):
     queryset = Actor.objects.all()
@@ -60,6 +61,14 @@ def get(self, request, *args, **kwargs):
     def put(self, request, *args, **kwargs):
         return self.update(request, *args, **kwargs)
 
+    def patch(self, request, *args, **kwargs):
+        actor = self.get_object()
+        serializer = ActorSerializer(actor, data=request.data, partial=True)
+        if serializer.is_valid():
+            serializer.save()
+            return Response(serializer.data)
+        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
+
     def delete(self, request, *args, **kwargs):
         return self.destroy(request, *args, **kwargs)
 
@@ -90,7 +99,19 @@ def get(self, request, pk):
 
     def put(self, request, pk):
         genre = self.get_object(pk)
-        serializer = GenreSerializer(genre)
+        serializer = GenreSerializer(genre, data=request.data)
+        if serializer.is_valid():
+            serializer.save()
+            return Response(serializer.data)
+        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
+
+    def patch(self, request, pk):
+        genre = self.get_object(pk)
+        serializer = GenreSerializer(
+            genre,
+            data=request.data,
+            partial=True
+        )
         if serializer.is_valid():
             serializer.save()
             return Response(serializer.data)