last_changed seems to have the current value?!

[andorardo]

Hi, I'm loving pyscript, but having trouble using the last_changed attribute.

I'd like to know how long since the sensor.xyz changed:

@state_trigger('sensor.xyz')
def xyz_change(**kwargs):
    last_changed = sensor.xyz.last_changed
    log.info(f"last_changed {last_changed}")

But from what I can tell, the last_changed value is always extremely recent (< 0.02 seconds ago), no matter what the last changed field shows in the developer tools. My guess is that it's showing the attribute for the new, current update

Is this working as intended?

Is it possible to get a hold of the 'from' state?

[craigbarratt]

Because the function call is executed immediately after the trigger, the state variable has just been updated, and, as you note, the last_changed is therefore very recent.

You can get the old_value (in kwargs) and use its last_changed attribute (although the first time, old_value will be None):

@state_trigger('sensor.xyz')
def xyz_change(old_value=None, **kwargs):
    last_changed = sensor.xyz.last_changed
    log.info(f"last_changed {last_changed}")
    if old_value is not None:
        log.info(f'  old_value {old_value} last_changed {old_value.last_changed}')

[andorardo]

Thanks! It's good to know that "the function call is executed immediately after the trigger", and the last_changed value has already been updated.