Change the datatype of 'enable_stats' to 'flag'

etc/emq.conf

@@ -113,8 +113,8 @@ mqtt.max_packet_size = 64KB
 ## Client Idle Timeout (Second)
 mqtt.client.idle_timeout = 30s
 
-## Enable client Stats: seconds or off
-mqtt.client.enable_stats = off
+## Enable client Stats: on | off
+mqtt.client.enable_stats = on
 
 ##--------------------------------------------------------------------
 ## MQTT Session
@@ -136,8 +136,8 @@ mqtt.session.max_awaiting_rel = 100
 ## Awaiting PUBREL Timeout
 mqtt.session.await_rel_timeout = 20s
 
-## Enable Statistics at the Interval(seconds)
-mqtt.session.enable_stats = off
+## Enable Statistics: on | off
+mqtt.session.enable_stats = on
 
 ## Expired after 1 day:
 ## w - week

priv/emq.schema

@@ -329,7 +329,7 @@ end}.
 %% @doc Enable Stats of Client.
 {mapping, "mqtt.client.enable_stats", "emqttd.client", [
   {default, off},
-  {datatype, [{duration, ms}, flag]}
+  {datatype, flag}
 ]}.
 
 %% @doc Client
@@ -375,7 +375,7 @@ end}.
 %% @doc Enable Stats
 {mapping, "mqtt.session.enable_stats", "emqttd.session", [
   {default, off},
-  {datatype, [{duration, ms}, flag]}
+  {datatype, flag}
 ]}.
 
 %% @doc Session Expiry Interval