Simple rule non triggered

Setup, Configuration and Use Scripts & Rules
1

Hi, I have made a simple setup on raspberry with openhab. I have one Thing and one Item like this:

Thing:

Thing exec:command:temperature [command="sudo python /home/pi/share/hab_dht22.py 22 4 T", interval=2, timeout=10]

Item:

String Temp2 "[%s]" <temperature> (gDHT) {channel="exec:command:temperature:output"}

Thing and Item works like a charm, but the rule that parse the string to float no:

rule "DHT Temp"
When
	Item Temp2 changed
Then
	logInfo("DHT", Temp2.state)
End

When the String Temp2 changed value (I can see that in Karaf), the rule is not triggered, I have no log in Karaf console.
Can you help me?

Thanks!!

2

I’m pretty sure that key words are case sensitive, try lower case

when, then, end

Leave “Item” uppercase, though.

3

Thanks! Right!
But now I get a null exception: When “Temp2 changed from 20.9 to 21.0” (as in Karaf console), I get:

Rule 'DHT Temp': An error occured during the script execution: Could not invoke method: org.eclipse.smarthome.model.script.actions.LogAction.logInfo(java.lang.String,java.lang.String,java.lang.Object[]) on instance: null.

It seems that Temp2 has null value…
Thanks
Roberto

4

Try this to see what is in your Temp2 and eliminate the error:

logInfo("DHT","Temp2: " + Temp2)

5

I get;

 Temp2: Temp2 (Type=StringItem, State=21.7, Label=, Category=temperature, Groups=[gDHT])

So, in my code, if I put:

logInfo("DHT", "Temp2: "+Temp2.State)

I get:

 Rule 'DHT Temp': An error occured during the script execution: The name '<XFeatureCallImplCustom>.State' cannot be resolved to an item or type
6

Lower case .state

7

Ok, now I have understand: if I put:

logInfo("DHT", Temp2.state)

I get the null exception; If I concat the value with a string, I get the right value:

logInfo("DHT", "Temp2: "+Temp2.state)

Thanks a lot!

8

This works because concatenation with a string will cast the item state to a string too.

Temp2.state.toString should work, too, without concatenation.

9

You really should use the Smarthome Designer to get rid of those typos!

http://docs.openhab.org/installation/designer.html