Nullable confidences in search results

arkindex/documents/serializers/search.py

@@ -27,12 +27,12 @@ class SolrDocumentSerializer(serializers.Serializer):
 
     transcription_id = serializers.UUIDField(allow_null=True)
     transcription_text = serializers.CharField(allow_null=True)
-    transcription_confidence = serializers.FloatField(min_value=0, max_value=1, required=False)
+    transcription_confidence = serializers.FloatField(min_value=0, max_value=1, allow_null=True)
     transcription_worker = serializers.CharField(allow_null=True)
 
     classification_id = serializers.UUIDField(allow_null=True)
     classification_name = serializers.CharField(allow_null=True)
-    classification_confidence = serializers.FloatField(min_value=0, max_value=1, required=False)
+    classification_confidence = serializers.FloatField(min_value=0, max_value=1, allow_null=True)
     classification_worker = serializers.CharField(allow_null=True)
 
     metadata_id = serializers.UUIDField(allow_null=True)