Using variables in when condition

is it possible to work with variables in when condition like this?

rule "Test"
val thing1 = "shelly:shelly1:xyz"
val thing2 = "shelly:shelly1:abc"
	Thing thing1 changed to OFFLINE or
	Thing thing2 changed to OFFLINE
	... whatever


Closest is to put all likely suspects in a Group (potentially all Items) and then check in the then section for “who triggered”, ignoring unwanted ones. The comparison can be between Item name and a variable.

Can’t put Things in a Group though …
there’s a Thing event handler here that might interest you

It works around OH2 limitations, and should be easier to implement in OH3

thanks for pointing out this solution.
I tried to adopt/create Yannicks rule directly in the code tab of MainUI’s rule designer but get the following error:

Script execution of rule with UID 'Test' failed: ReferenceError: "event" is not defined in <eval> at line number 1
  - id: "1"
    label: When ThingStatusInfoChangedEvent is raised
      eventTypes: ThingStatusInfoChangedEvent
      eventTopic: openhab/*
    type: core.GenericEventTrigger
conditions: []
  - inputs: {}
    id: "2"
    label: execute a given script
      type: application/javascript
      script: print(event.topic.split('/')[2]);print(JSON.stringify(event.payload));print(event.toString());
    type: script.ScriptAction

I don’t think print works in JS rules. You’ll want to use a logger and log it out to openhab.log.

event is an object (a Java Object I think) that encapsulates the the event that triggered the rule. And event sometimes doesn’t even get injected into the rule at all. I don’t think event gets defined for Thing Status events.

But I don’t do anything with Thing status events and rules. Most bindings do the reasonable thing and set the Items to UNDEF when they go OFFLINE so I just use my Items going to UNDEF.

I found that JS print output to karaf console on OH2.
No idea what happens in OH3.

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hmm. and it is event which raises the error.
print is only a step between. In the end I just wanted to map it to an item.

When are you running this rule exactly? The “test run” feature of UI rules is useless here, it does not provide a fake event object for you.

grr. should have thought about this by myself…
still have an error

[ERROR] [] - Error on event handling.
java.lang.NullPointerException: null
	at java.lang.String.contains( ~[?:?]
	at org.openhab.core.automation.internal.module.handler.GenericEventTriggerHandler.apply( ~[?:?]
	at ~[?:?]
	at ~[?:?]
	at ~[?:?]
	at$0( ~[?:?]
	at [?:?]

So, what event caused that? Looks like the trigger mechanism exploding.

I forced a change of thing status by disabling a thing

wait. probably at some stage

eventSource: ""

was deleted from yaml code.
works now like a charm

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Please let us know if you can get the trigger to filter on event topic, that never worked for me in OH2.

if this is the correct syntax for filtering:

eventTopic: openhab/things/shelly*/*

then this does not work