1. ZPL II, ZBI 2, Set-Get-Do, Mirror, WML Programming Guide
  2. SGD Command Reference
  3. mqtt.conn[1|2].clean_session_flag
  • ZPL II, ZBI 2, Set-Get-Do, Mirror, WML Programming Guide
mqtt.conn[1|2].clean_session_flag

mqtt.conn[1|2].clean_session_flag

This command specifies whether to clear all previous values on MQTT connection 1 or MQTT connection 2. When set to
"on"
, the default, the broker does not create a persistent session for new connections. If the client disconnects, any messages in the queue are lost. When set to
"off"
, the broker creates a persistent session and any messages in the queue persist if the client disconnects. The persisted messages are sent when the client reconnects.

Setvar

To persist MQTT messages on MQTT connections:
! U1 setvar "mqtt.conn1.clean_session_flag" "value"
! U1 setvar "mqtt.conn2.clean_session_flag" "value"
Values
  • "on"
     (default) the broker does not persist MQTT message on connection 1.
  • "off"
     causes the broker to persist messages
Default
"on"

Getvar

To have the printer return the value of the MQTT session flag for connection 1:
! U1 getvar "mqtt.conn1.clean_session_flag"
! U1 getvar "mqtt.conn2.clean_session_flag"
Values
  • "on"
     (default) the broker does not persist MQTT message on connection 1.
  • "off"
     causes the broker to persist messages