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IoT Events: Publish IoT Topic action with dynamic topic name


I'd like to be able to publish a message to a topic, which name is build up dynamically based on one of the input values. I can access to the input already when setting up Transition Events, but can't find a way to interpolate the input value into the topic name.

Suppose I have an input such as: $ = bar Would like to use it in the topic name as: "my/topic/$", resulting into "my/topic/bar"

Have tried all type of proposed substitution templates w/o success (

1 Answer

Answering to my own question, after some further testing. I did not manage to interpolate the topic dynamically on-the-fly as I wanted. Instead, I found a workaround by declaring a variable that contains the resolved interpolation in a previous state. For instance, the variable leds_topic is initialized with 'gate/' + $input.gate_sensors.gateid + '/leds' Aterwards, I can publish to that topic using as Topic name ($variable.leds_topic)

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answered 4 months ago

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