Simple adding of two items

[Hoerli]

Hello Forum,

I thought it would be simple, but apparently it is not.

I have two items which are both numbers.
These two items should be added together so that I can continue working with the result.
In short, there are two inverters and I want to add the current yield.

I have built a simple script in Blockly, which should add the two values and write this to the item “Total Yield”.
Unfortunately the item always stays at NULL.

I have tried several possibilities, which I have also found here in the forum, has only brought nothing so far.
The item remains at NULL
Trying to format all values into a string did not work either.
I created a second item, which was formatted as a string instead of a number.

What am I doing wrong?
How do I do it correctly?

[hafniumzinc (T)]

Please show the configuration of the two Items which you are trying to add.

[Hoerli]

Here is the configuration.
Both items are set up identically.

[hafniumzinc (T)]

When you run your rule, what do the logs show?

[Hoerli]

I can pull the following info from the logs:

events.log
2022-11-19 17:08:43.767 [INFO ] [openhab.event.RuleUpdatedEvent ] - Rule 'GesamtertragRechner' has been updated.

openhab.log

2022-11-19 17:09:14.826 [ERROR] [e.automation.internal.RuleEngineImpl] - Failed to execute rule ‘GesamtertragRechner' with status 'UNINITIALIZED'
2022-11-19 17:09:50.345 [ERROR] [ipt.internal.ScriptEngineManagerImpl] - ScriptEngine for language 'application/javascript' could not be found for identifier: 993a26f2-5e49-45a4-a0ee-a527157da7a6

[hafniumzinc (T)]

Well, looks like there’s a problem with Javascript not being found. Do you have any other Blockly rules running/working?

[Hoerli]

No, I even set up a test instance, where only openhab is running in it so far.
(x86/x64)

[Hoerli]

I think I found a problem here with JavaScript in general on x86/x64.
I have once again set up a fresh installation of openHAB in a proxmox container.

After that I installed the Modbus binding and the two addons “JavaScript Scripting” and “JavaScript Transformation Service”.
Additionally I created a small JavaScript in the transformations folder:

(function(inputData) {
    if(inputData < 0) return "0";
    return parseFloat(inputData) ;
})(input)

As soon as I assign the JavaScript to a Thing, I always get only NULL as result of the item state and the following error messages in the openhab log:

2023-01-08 19:50:16.495 [WARN ] [rt.modbus.internal.ModbusManagerImpl] - Execution of scheduled (5000ms) poll task BasicPollTask [getEndpoint=ModbusIPSlaveEndpoint [address=192.168.178.161, port=502], request=ModbusReadRequestBlueprint [slaveId=3, functionCode=READ_INPUT_REGISTERS, start=30769, length=26, maxTries=3], getResultCallback()=org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator@5bb4d35e, getFailureCallback()=org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator@5bb4d35e] failed unexpectedly. Ignoring exception, polling again according to poll interval.
java.lang.NullPointerException: null

2023-01-08 19:56:34.240 [WARN ] [rt.modbus.internal.ModbusManagerImpl] - Execution of scheduled (5000ms) poll task BasicPollTask [getEndpoint=ModbusIPSlaveEndpoint [address=192.168.178.161, port=502], request=ModbusReadRequestBlueprint [slaveId=3, functionCode=READ_INPUT_REGISTERS, start=30769, length=26, maxTries=3], getResultCallback()=org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator@5e6214e8, getFailureCallback()=org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator@5e6214e8] failed unexpectedly. Ignoring exception, polling again according to poll interval.
java.lang.NullPointerException: Cannot invoke "javax.script.Compilable.compile(java.io.Reader)" because "engine" is null
        at org.openhab.transform.javascript.internal.JavaScriptEngineManager.getCompiledScriptByFilename(JavaScriptEngineManager.java:77) ~[?:?]
        at org.openhab.transform.javascript.internal.JavaScriptTransformationService.transform(JavaScriptTransformationService.java:119) ~[?:?]
        at org.openhab.binding.modbus.internal.SingleValueTransformation.transform(SingleValueTransformation.java:140) ~[?:?]
        at org.openhab.binding.modbus.internal.CascadedValueTransformationImpl.transform(CascadedValueTransformationImpl.java:51) ~[?:?]
        at org.openhab.binding.modbus.internal.ValueTransformation.transformState(ValueTransformation.java:48) ~[?:?]
        at org.openhab.binding.modbus.internal.handler.ModbusDataThingHandler.lambda$16(ModbusDataThingHandler.java:1001) ~[?:?]
        at java.util.HashMap$KeySpliterator.forEachRemaining(HashMap.java:1707) ~[?:?]
        at java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762) ~[?:?]
        at org.openhab.binding.modbus.internal.handler.ModbusDataThingHandler.processUpdatedValue(ModbusDataThingHandler.java:969) ~[?:?]
        at org.openhab.binding.modbus.internal.handler.ModbusDataThingHandler.onRegisters(ModbusDataThingHandler.java:847) ~[?:?]
        at org.openhab.binding.modbus.internal.handler.ModbusDataThingHandler.lambda$11(ModbusDataThingHandler.java:801) ~[?:?]
        at java.util.Optional.ifPresent(Optional.java:178) ~[?:?]
        at org.openhab.binding.modbus.internal.handler.ModbusDataThingHandler.onReadResult(ModbusDataThingHandler.java:801) ~[?:?]
        at org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator.lambda$2(ModbusPollerThingHandler.java:144) ~[?:?]
        at java.util.concurrent.CopyOnWriteArrayList.forEach(CopyOnWriteArrayList.java:807) ~[?:?]
        at org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator.notifyChildren(ModbusPollerThingHandler.java:142) ~[?:?]
        at org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator.handleResult(ModbusPollerThingHandler.java:88) ~[?:?]
        at org.openhab.binding.modbus.handler.ModbusPollerThingHandler$ReadCallbackDelegator.handle(ModbusPollerThingHandler.java:105) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusLibraryWrapper.invokeCallbackWithResponse(ModbusLibraryWrapper.java:337) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusManagerImpl$PollOperation.lambda$1(ModbusManagerImpl.java:216) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.SimpleStopWatch.timeRunnable(SimpleStopWatch.java:152) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusManagerImpl$PollOperation.accept(ModbusManagerImpl.java:216) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusManagerImpl$PollOperation.accept(ModbusManagerImpl.java:1) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusManagerImpl.executeOperation(ModbusManagerImpl.java:614) ~[?:?]
        at org.openhab.core.io.transport.modbus.internal.ModbusManagerImpl$ModbusCommunicationInterfaceImpl.lambda$1(ModbusManagerImpl.java:812) ~[?:?]
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539) [?:?]
        at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:305) [?:?]
        at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:305) [?:?]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136) [?:?]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635) [?:?]
        at java.lang.Thread.run(Thread.java:833) [?:?]

As soon as I change it to “default”, the error is gone, but my values are not correct.
On a Raspberry Pi 4B the whole thing runs without problems.
There is only openHAB installed for a long time and also a few other Linux packages.

[glhopital (Gaël L'hopital)]

What JDK version are you using ? I had the same error message with OH3.4 under v17. Switched back to v11 all is fine.

[Hoerli]

Thanks for the tip, I actually installed 17.
Will give it a try.