refactor: clean up scaffolding backend

backend/letters/views.py

@@ -8,11 +8,12 @@ from letters.serializers import LetterSerializer
 
 class LetterView(generics.ListCreateAPIView):
     serializer_class = LetterSerializer
-    # enforce auth guard
     permission_classes = [IsAuthenticated]
 
     def get_queryset(self):
-        """return only letters of the authenticated user"""
+        """
+        Returns the letters of the authenticated user.
+        """
         return Letter.objects.filter(user=self.request.user)
 
 
@@ -21,33 +22,37 @@ class LetterDetailView(generics.RetrieveUpdateDestroyAPIView):
     lookup_field = "public_id"
 
     def get_permissions(self):
+        """
+        Allow any letter GET requests for guest access and enforce authentication for other operations.
+        """
         if self.request.method == "GET":
             return [AllowAny()]
         return [IsAuthenticated()]
 
     def get_queryset(self):
+        """
+        Returns the letters of the authenticated user.
+        Guests can only see SEALED letters.
+        """
         if self.request.user.is_authenticated:
-            # author can see all their letters (DRAFT, SEALED, etc.)
             return Letter.objects.filter(user=self.request.user)
-        # guests can ONLY see SEALED letters
         return Letter.objects.filter(status=Letter.Status.SEALED)
 
     def put(self, request, public_id):
-        # upsert: create if doesn't exist, else update
+        """
+        Upserts letters: create if doesn't exist, else update.
+        Validates the payload data, cleans up old images, and returns the upserted data.
+        """
         letter, created = Letter.objects.get_or_create(public_id=public_id, user=request.user)
 
-        # check if already sealed
         if not created and letter.status == Letter.Status.SEALED:
             return Response({"error": "Sealed letters cannot be modified."}, status=400)
 
-        # request.data handles both JSON and Multipart automatically in DRF
-        serializer = self.get_serializer(letter, data=request.data, partial=True)
-        serializer.is_valid(raise_exception=True)
-        serializer.save()
+        write_serializer = self.get_serializer(letter, data=request.data, partial=True)
+        write_serializer.is_valid(raise_exception=True)
+        write_serializer.save()
 
-        # Note: image_files is a list of binary files in request.FILES
         if "image_files" in request.FILES:
-            # Delete old image files from storage and database
             for old_image in letter.images.all():
                 old_image.file.delete(save=False)
                 old_image.delete()
@@ -55,6 +60,5 @@ class LetterDetailView(generics.RetrieveUpdateDestroyAPIView):
             for image_file in request.FILES.getlist("image_files"):
                 LetterImage.objects.create(letter=letter, file=image_file, file_name=image_file.name)
 
-        # Return fresh data including the new image URLs
-        serializer = self.get_serializer(letter)
-        return Response(serializer.data, status=201 if created else 200)
+        response_serializer = self.get_serializer(letter)
+        return Response(response_serializer.data, status=201 if created else 200)