Restore DateTime ignoring timezone

Add-ons Persistence Services
1

Hello there,

I calculate a time difference in my rule and store it in a DateTime item.
Persistence is done via InfluxDB.
Item is declared like this:

DateTime Waschkueche_Waschmaschine_letzteZykluszeit "Letzte Waschdauer [%1$tH:%1$tM h]" (Waschkueche, Zeit)

Database persists the correct value:

> select * from Waschkueche_Waschmaschine_letzteZykluszeit
name: Waschkueche_Waschmaschine_letzteZykluszeit
time                value
----                -----
1516470604809000000 11554769

The sitemap shows 03:12 h after the rule updates the value but 04:12 h after the value is restored from the database.
How can I set up that no timezone offset is applied to this value when it is restored?

2

You should not do that. DateTime is designed to store absolute dates and times and is not suitable for storing durations.

You need to store the duration as a Number (number of minutes, number of seconds, number of milliseconds) and use a JS transform in the Item’s label or a Rule and a Proxy Item to convert that Number to Hours and Minutes.

Here is the JS transform I use to convert the uptime reported by my sonoffs in hours to days:hours:minutes:seconds.

(function(i) {
    if(isNaN(i)) return "NA";
    var days = Math.floor(i/24);
    var hours = i%24;
    var pad = "00";
    return days+":"+(pad+hours).slice(-pad.length)+":00:00";
})(input)
3

thank you very much, I will change this.

4

Hi Rich,
How do you enable your JS transform for the uptime in the paper UI?

5

I don’t. I define all my Items in .items files.

But to use it you store the minutes or hours in a Number Item and apply the transform to the label as documented here.

6

I still don’t get how its done with files, as I usually create just the items in conf files, and from Paper UI , just create new items that link to the various parameters.

Could you show your example?
much thanks!

7

Just replace the label for the Item in PaperUI with JS(hours2mins.js):%s.

Creating Items in .items files is https://www.openhab.org/docs/configuration/items.html

8

What should the thing look like? also with the JS transformation info?

Thing:

Type number : uptime	"Uptime"			   [ stateTopic="tele/sonoff/MFC/STATE", transformationPattern="JS:uptime.js"]

Item:

Number XeroxMFC_Uptime "Uptime [JS(uptime.js):%s]" { channel= "mqtt:topic:mosquitto:MFC:uptime" }
9

I don’t use .things files. But the Thing is irrelevant. So long as it is a Number type Channel linked to a Number Item, you just need to transform the label of the Item.