diff --git a/artiq/frontend/artiq_influxdb.py b/artiq/frontend/artiq_influxdb.py
index f0ffa350d..0dbd740c5 100755
--- a/artiq/frontend/artiq_influxdb.py
+++ b/artiq/frontend/artiq_influxdb.py
@@ -131,6 +131,9 @@ class _Mock:
     def __delitem__(self, k):
         pass
 
+    def append(self, v):
+        pass
+
 
 class Datasets:
     def __init__(self, filter_function, writer, init):