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Function: MQTTUnSubscribe
Property window:
Short description:
Allow to connect to an “IoT” broker using the MQTT protocol to actively unsubscribe from a channel.
Long Description:
Some brokers (e.g. Kafka) have a “memory” of all the messages that passes through them. These brokers are waiting for a subscriber to (re-)start (i.e. they are waiting for the Anatella process to re-start) and, once the Anatella process is started, they forward all the saved messages to it: They forward all the messages that are inside the subscribed channel(s) and that were not yet processed by the subscriber. To prevent the broker to save into its memory all the messages, you need to actively tell to the broker that you don’t want to receive any message anymore in the future: This is the exact objective of the “MQTT Unsubscribe” Action.