OH3: update a datetime item with a ZonedDateTime

Setup, Configuration and Use Migration
1
  • openhabian 3.3.0 on rPi4

I have a decimal time of say 6.75
Then turn this into hours and minutes.
Then update a DateTime item, which fails

        val time_to_charge = TeslaM3_time_to_full_charge.state as DecimalType
        logInfo(logPrefix + "02.01", "time_to_charge {}", time_to_charge)

        val hours = (Math::floor(time_to_charge.floatValue)).intValue
        logInfo(logPrefix + "02.02", "hours {}", hours)

        val minutes = Math::round((time_to_charge.floatValue - hours) * 60)
        logInfo(logPrefix + "02.03", "minutes {}", minutes)

        val charged_at_time = ZonedDateTime.now().plusHours(hours).plusMinutes(minutes)
        logInfo(logPrefix + "02.04", "charged_at_time {}", charged_at_time)

        TeslaM3_time_charged.postUpdate(charged_at_time)
        logInfo(logPrefix + "02.05", "TeslaM3_time_charged {}", TeslaM3_time_charged.state)

This line fails:

        TeslaM3_time_charged.postUpdate(charged_at_time)

Here the log:

2022-11-10 22:01:00.484 [INFO ] [ab.core.model.script.testRules.02.01] - time_to_charge 6.75
2022-11-10 22:01:00.487 [INFO ] [ab.core.model.script.testRules.02.02] - hours 6
2022-11-10 22:01:00.490 [INFO ] [ab.core.model.script.testRules.02.03] - minutes 45
2022-11-10 22:01:00.493 [INFO ] [ab.core.model.script.testRules.02.04] - charged_at_time 2022-11-11T04:46:00.491425+10:00[Australia/Brisbane]
2022-11-10 22:01:00.496 [INFO ] [ab.core.model.script.testRules.02.05] - TeslaM3_time_charged 2022-11-11T04:45:30.491524+1000

Any hints appreciated.

I had a look at this:

But it does not sink in what type I have in charged_at_time.
I thought it was DateTime?!

2

Well, further reading and trial and error, this works:

TeslaM3_time_charged.postUpdate(DateTimeType.valueOf(charged_at_time.toLocalDateTime().toString()))

2022-11-10 22:15:30.879 [INFO ] [ab.core.model.script.testRules.02.02] - hours 6
2022-11-10 22:15:30.882 [INFO ] [ab.core.model.script.testRules.02.03] - minutes 30
2022-11-10 22:15:30.885 [INFO ] [ab.core.model.script.testRules.02.04] - charged_at_time 2022-11-11T04:45:30.884094+10:00[Australia/Brisbane]
2022-11-10 22:15:30.889 [INFO ] [ab.core.model.script.testRules.02.05] - TeslaM3_time_charged 2022-11-11T04:45:00.880009+1000
3

Wouldn’t that be a duration, a period of time, not a datetime, a specific instant in the life of the world?

EDIT okay ignore that, you are trying to predict an instant I think.

4

I would have expected that to work on Rules DSL. What’s not clear here is how that line fails. There is no error in the log.

Right now you have a java.time.ZonedDateTime in changed_at_time. You started with a ZonedDateTime and manipulated it’s state but did change it’s type.

That’s a little overworked. This should work.

TeslaM3_time_charged.postUpdate(new DateTimeType(charged_at_time))

This should work too:

TeslaM3_time_charged.postUpdate(charged_at_time.toLocalDateTime().toString()))

But over all I would expect both of these to work too.

TeslaM3_time_charged.postUpdate(charged_at_time)
TeslaM3_time_charged.postUpdate(charged_at_time.toString())

Running with this, here is how it would be done with a Duration.

val myDur = Duration.ofHours(hours).plusMinutes(minutes)
val charged_at_time = now.plus(myDur)

There could be times where working with a duration might be easier, I’m not sure this is one of them.

But overall, I think it would make sense to just calculate the minutes and forget the hours. I think the following would work:

val time_to_charge = TeslaM3_time_to_full_charge.state as Number // It's better to cast to Number than DecimalType
val minutes = Math:round(time_to_charge * 60)
TeslaM3_time_charged.postUpdate(now.plusMinutes(minutes).toString())

Using a Duration gives you some convenience functions that might prove useful.

val time_to_charge = TeslaM3_time_to_full_charge.state as Number
val dur = Duration.ofMinutes(time_to_charge * 60)
// dur.toString() will print the duration in ISO8601 format, e.g. 6 hours 45 minutes would be PT6h45m
// dur.toHours() gives you just the hours
// dur.toMinutesPart() gives you the minutes after subtracting the hours
TeslaM3_time_charged.postUpdate(now.plus(dur).toString())
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5

What I had…

In OH2 I had:

        spm_LastUpdate.postUpdate(new DateTimeType())

So I thought I stick the time into the brackets and should be OK; but it threw an error I can no longer trace, as I tried a few iterations.

Anyway, I put your suggested:

        TeslaM3_time_charged.postUpdate(new DateTimeType(charged_at_time))

… into the rule, and indeed it works.

Again, thank you for your detailed explanation… always appreciate your’s too rossko57 :slight_smile:

The Tesla API returns “time_charged_to_set_level” as decimal number. I am too lazy calculating the end time in my head, as it will change based on solar PV power levels.

6

Right, but you can convert that number to just minutes and save a step calculating the hours. That’s the point of my reductions. now.plusHours(5).plusMinutes(10) is the same as now.plusMinutes(310).

1 Like