Script crashes on undefined variable, but it is defined (I think)

Configuration
1

I wrote a script to switch on or off lights or switches that are in a mixed state (some are on, some are off) in an area

mixed_switch:
    sequence:
        -   alias: set variables
            variables:
                # retrieve area from automation parameters 
                area: "{{ area }}"
                # get all switches in the area
                switches: "{{ expand(area_entities(area)) | selectattr('domain', 'eq', 'switch')| map(attribute = 'entity_id') | list }}"
                # check which switches are on and off
                count_on_switches: "{{ expand(lights) | selectattr('state','eq', 'on') | list | count }}"
                count_off_switches: "{{ expand(lights) | selectattr('state','eq', 'off') | list | count }}"
                # idem for lights
                lights: "{{ expand(area_entities(area)) | selectattr('domain', 'eq', 'light')| map(attribute = 'entity_id') | list }}"
                count_on_lights: "{{ expand(lights) | selectattr('state','eq', 'on') | list | count }}"
                count_off_lights: "{{ expand(lights) | selectattr('state','eq', 'off') | list | count }}"
                # depending on how many devices are on and off make the decision of the global state
                light_action: "{{ iif( count_on_switches + count_on_lights >= count_off_switches + count_off_lights, 'off', 'on' ) }}"
        -   alias: debug variables
            service: persistent_notification.create
            data:
                message: "{{switches}} {{count_on_switches}} {{count_off_switches}} {{lights}} {{count_on_lights}} {{count_off_switches}} {{light_action}} area: {{area}}"
                title: "debug"
        -   alias: turn all lamps on or off
            service: homeassistant.turn_{{ light_action }}
            target:
                area_id: 
                    - "{{ area_id(area) }}"

The first version of this script only assessed switches and worked. This one, however, crashes with

domotique-hass-1  | 2023-02-11 20:11:23.274 ERROR (MainThread) [homeassistant.components.script.mixed_switch] mixed_switch: Error executing script. Error rendering template for variables at pos 1: UndefinedError: 'lights' is undefined

I did all kinds of tests in the Dev elopment Tools to replicate the script and all the bts work fine. For instance

{% set a =  expand(area_entities('parents | lights')) | selectattr('domain', 'eq', 'light')| map(attribute = 'entity_id') | list %}
{{ expand(a) | selectattr('state','eq', 'off') | list | count }}

correctly outputs 2 (two lights in the area are indeed off).

What does the error exactly mean?

2

The issue is actually that count_on_switches and count_off_switches reference lights instead of switches.

1 Like
3

Oh yes, thank you. I was copy/pasting and forgot to change that part. Thank you!

4

Also, it is very important when using Area-based templates to be aware that there are often entities within the light and switch domains that you might not think about. You will need to reject these from your templates and update the reject list any time you add devices to an area.

5

Yes. The solution I ultimately went for was to have the devices put in, say, “bedroom | general” and then manually select the entities that are actually light sources and put them in “bedroom | lights” and use that new area in the automation.

This is not really elegant but the best I came up with.