Allow None to certain int parameters

model_server/base/roiset.py

@@ -30,13 +30,13 @@ class PatchParams(BaseModel):
     focus_metric: str = 'max_sobel'
     rgb_overlay_channels: Union[List[Union[int, None]], None] = None
     rgb_overlay_weights: List[float] = [1.0, 1.0, 1.0]
-    pad_to: int = 256
+    pad_to: Union[int, None] = 256
     expanded: bool = False
 
 
 class AnnotatedZStackParams(BaseModel):
     draw_label: bool = False
-    channel: int = None
+    channel: Union[int, None] = None
 
 
 class RoiFilterRange(BaseModel):