sakipping null values in scribe message

Summary: since we have added flexibility for different sets of metrics per operater we want to skip messages for empty metrics

Reviewed By: nmacchioni

Differential Revision: D64345289

fbshipit-source-id: d5b1fff90c6acd530867d0b6ef3ea97bc6f41cf5

scripts/userbenchmark/upload_scribe.py

@@ -27,6 +27,8 @@ def format_message(self, field_dict):
         assert "time" in field_dict, "Missing required Scribe field 'time'"
         message = defaultdict(dict)
         for field, value in field_dict.items():
+            if value is None:
+                continue
             if field in self.schema["normal"]:
                 message["normal"][field] = str(value)
             elif field in self.schema["int"]: