ltm rule command MQTT dup

iRule(1)					  BIG-IP TMSH Manual					     iRule(1)

MQTT::dup
       Get or set duplicate flag of MQTT PUBLISH message.

SYNOPSIS
       MQTT::dup ('0' | '1')?

DESCRIPTION
       This command can be used to get or set duplicate flag of MQTT message.  This command is valid only for
       following MQTT message types:

	   PUBLISH

       Syntax

       MQTT::dup [ 0 | 1 ]

       MQTT::dup
	   * Get the duplicate flag of MQTT PUBLISH message.

       MQTT::dup 0
	   * reset the duplicate flag of MQTT PUBLISH message. This will convert the
	     message to as if it was the first occasion that client or server has
	     attempted to  send this MQTT PUBLISH message.

       MQTT::dup 1
	   * Set the duplicate flag of MQTT PUBLISH message. This will convert the message
	     to as if the message was a redelivery of an earlier attempt to send the message.

RETURN VALUE
       When called without an argument, this command returns the duplicate flag of MQTT message.

VALID DURING
       MQTT_CLIENT_INGRESS MQTT_SERVER_INGRESS MQTT_CLIENT_DATA MQTT_SERVER_DATA MQTT_CLIENT_EGRESS
       MQTT_SERVER_EGRESS

EXAMPLES
	#Downgrading QoS to 0:

	when MQTT_CLIENT_INGRESS {
	    set type [MQTT::type]
	    switch $type {
		"PUBLISH" {
		    set in_qos [MQTT::qos]
		    if { $in_qos > 0 } {
			set pktid [MQTT::packet_id]
		    }
		    MQTT::dup 0
		    MQTT::qos 0
		    if { $in_qos == 1 } {
			MQTT::respond type PUBACK packet_id $pktid
		    } elseif { $in_qos == 2 } {
			MQTT::respond type PUBREC packet_id $pktid
		    }
		}
		"PUBREL" {
		    set pktid [MQTT::packet_id]
		    MQTT::drop
		    MQTT::respond type PUBCOMP packet_id $pktid
		}
	    }
	}

HINTS
SEE ALSO
CHANGE LOG
       @BIGIP-13.0.0 --First introduced the command.

BIG-IP						      2020-06-23					     iRule(1)