fix: Use anyio.SpooledTemporaryFile in UploadFile

starlette/formparsers.py

@@ -250,30 +250,29 @@ async def parse(self) -> FormData:
 
         # Create the parser.
         parser = multipart.MultipartParser(boundary, callbacks)
-
-        async with AsyncExitStack() as stack:
-            for file in self._files_to_close_on_error:
-                stack.push_async_callback(file.aclose)
-
-            try:
-                # Feed the parser with data from the request.
-                async for chunk in self.stream:
-                    parser.write(chunk)
-                    # Write file data, it needs to use await with the UploadFile methods
-                    # that call the corresponding file methods *in a threadpool*,
-                    # otherwise, if they were called directly in the callback methods above
-                    # (regular, non-async functions), that would block the event loop in
-                    # the main thread.
-                    for part, data in self._file_parts_to_write:
-                        assert part.file  # for type checkers
-                        await part.file.write(data)
-                    for part in self._file_parts_to_finish:
-                        assert part.file  # for type checkers
-                        await part.file.seek(0)
-                    self._file_parts_to_write.clear()
-                    self._file_parts_to_finish.clear()
-            except MultiPartException as exc:
-                raise exc
+        try:
+            # Feed the parser with data from the request.
+            async for chunk in self.stream:
+                parser.write(chunk)
+                # Write file data, it needs to use await with the UploadFile methods
+                # that call the corresponding file methods *in a threadpool*,
+                # otherwise, if they were called directly in the callback methods above
+                # (regular, non-async functions), that would block the event loop in
+                # the main thread.
+                for part, data in self._file_parts_to_write:
+                    assert part.file  # for type checkers
+                    await part.file.write(data)
+                for part in self._file_parts_to_finish:
+                    assert part.file  # for type checkers
+                    await part.file.seek(0)
+                self._file_parts_to_write.clear()
+                self._file_parts_to_finish.clear()
+        except MultiPartException as exc:
+            # Close all the files if there was an error.
+            async with AsyncExitStack() as stack:
+                for f in self._files_to_close_on_error:
+                    stack.push_async_callback(f.aclose)
+            raise exc
 
         parser.finalize()
         return FormData(self.items)