I have a C8 running the latest software. I have a bunch of Group Switches that handle things like the "First Floor", "Second Floor", "Outside", etc. I would like to notify based on the lights being on/off within a given Group - so I need to notify on the "groupState" field. If I notify on the Switch on/off status, it will notify every time I instruct that Group Switch to go on/off, but if a command fails or otherwise - then I'll get a "false" notification - as the switch will go off.
I've noticed that with the "Rule Machine" I can build a trigger based on a Custom Attribute, but this seems to have a few downsides that make this rather complex:
Can only trigger on a single device at a time
Must specify the text that you're looking for ie, "allOn, allOff, someOn"
Ideally, I'd notify any time the "groupState" changes status.
While what you're asking should more or less be possible, with the caveats you've noted, would simply changing the options on your group work? The on/off state only updates without really "checking" the devices if you don't have one of the options set in the Group app, like "Use group device to indicate if any members are on" (or off)." This won't help if the command worked for some but not all, but neither would looking at groupState if they weren't some other way to start.
A significant advantage of this option is that by using the standard switch attribute, you open up compatibility with a lot more apps (or standard features of apps you can use either way like Rule Machine) -- the trick is to configure it in the Group app to behave how you want.
