ltm rule command MQTT collect

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

MQTT::collect
       Collect the specified amount of MQTT message payload data

SYNOPSIS
       MQTT::collect (COLLECT)?

DESCRIPTION
       Collects the specified amount of MQTT message payload data before triggering a MQTT_CLIENT_DATA or
       MQTT_SERVER_DATA event.

       When collecting data in a clientside event, the MQTT_CLIENT_DATA event will be triggered.  When collecting
       data in a serverside event, the MQTT_SERVER_DATA event will be triggered.

       This command is valid only for following MQTT message types:

	   PUBLISH

       This command allows you to perform various operations on MQTT PUBLISH message like modify its contents.	NOTE:
       Please make sure that MQTT PUBLISH message expects to receive a payload by using [MQTT::payload length].  This
       is to make sure that the payload length is not zero before calling this command.

       Syntax

       MQTT::collect []

       MQTT::collect
	   Collect the entire payload of the MQTT message. To stop collecting
	   use MQTT::release command.

       MQTT::collect 
	   Collect  bytes of payload of the MQTT message.
	   If paylaod is smaller than  collect entire payload.
	   The collected data can be accessed via the MQTT::payload command.
	   To stop collecting use MQTT::release command.

RETURN VALUE
VALID DURING
       MQTT_CLIENT_INGRESS MQTT_CLIENT_DATA MQTT_SERVER_INGRESS MQTT_SERVER_DATA

EXAMPLES
	#Example: Prohibit PUBLISH payloads with blocked keywords defined in
	#blacklisted_keywords_datagroup in first 200 bytes
	#
	when MQTT_CLIENT_INGRESS {
	    set type [MQTT::type]
	    switch $type {
	       "PUBLISH" {
		  if { [class exists  blacklisted_keywords_datagroup] } {
		     MQTT::collect 200
		  }
	       }
	    }
	}

	when MQTT_CLIENT_DATA {
	   set type [MQTT::type]
	   switch $type {
	       "PUBLISH" {
		  set payload [MQTT::payload]
		  MQTT::release
		  set found [class match $payload contains blacklisted_keywords_datagroup]
		  if { $found != "" } {
		      MQTT::disconnect
		  }
	       }
	   }
	}

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

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