[SOLVED] Persistance RRD4J - Change since midnight

Add-ons Persistence Services
1

Hi

I have persisted the item “LG_Resus_Charge_Tot” which shows the total amount of charged battery energy.
Now I would like to know only the todays value. Something like this:

Actual Value - Value at midnight

I already tried if something like this is working, but without success:

rule "Test"
	when
		Item LG_Resus_Charge_Tot changed
	then
		var Number today = LG_Resus_Charge_Tot.changeSince(now.minusMinutes(30), "rrd4j").state as DecimalType
		postUpdate(LG_Resus_Charge_Day, today)									    					
	end

Any ideas how I can get this value? Is another persistance service needed than rrd4j? The persistance itself is working (everyMinute)

Thanks
Michael

2

There seems to be a DSP-problem OpenHAB not saving mesaurements after daylight saving time change

3

I’m already on snapshot 1238, so this should be fixed in my setup.

My question is more how the rule should look like. Because my understanding is that I don’t get the value with “changeSince”. The rule that I have posted was only for testing with last 30 minutes…at the end the delta between now and last midnight is needed.

4

Found it:

var Number today = LG_Resus_Charge_Tot.deltaSince(now.toDateMidnight, “rrd4j”)