if result not nun check

Signed-off-by: Ebbe Baß <ebbe.bass>

server/app.py

@@ -123,6 +123,7 @@ def start_mqtt_publishers():
                 #Checks to see if the current packet is for the specified DMX Universe
                 dmxPacket = artNetPacket.data
                 # Create MQTT topic based on the universe and channel
+                if result is not None:
                     for row in result:
                         dmx_address = int(row[2])
                         if artNetPacket.universe == int(row[1]):