fix map_metadata processor on deprecated processors/datasets

processors/conversion/view_metadata.py

@@ -64,12 +64,13 @@ def process(self):
 				metadata_file = json.load(file)
 
 		parent_processor = self.dataset.get_parent().get_own_processor()
-		self.dataset.log(f"Collecting metadata created by {parent_processor.type}")
-		if not hasattr(parent_processor, "map_metadata"):
-			self.log.warning(f"Metadata formatter processor cannot run on {parent_processor.type}; has no 'map_metadata' method")
-			self.dataset.update_status("Cannot reformat metadata", is_final=True)
+		if parent_processor is None or not hasattr(parent_processor, "map_metadata"):
+			if parent_processor is not None:
+				self.log.warning(f"Metadata formatter processor cannot run on {parent_processor.type}; map_metadata method not implemented")
+			self.dataset.update_status("Cannot reformat metadata for this dataset", is_final=True)
 			self.dataset.finish(0)
 			return
+		self.dataset.log(f"Collecting metadata created by {parent_processor.type}")
 
 		include_failed = self.parameters.get("include_failed", False)
 		rows = []