[SOLVED] String item not updating from TCP binding

[emaildave82]

Hi All,
Hoping someone can help - I have a String item bound to a TCP socket that isn’t updating when a string comes in over the socket.

(I couldn’t get it to work on OH2, so now on OH1.8 and having the exact same issue)

I have in openhab.cfg:
tcp:updatewithresponse=true

My item:
String amx {tcp="<[10.0.1.63:*:default]"}

I see this in the terminal so I know the string is coming into the socket:
2018-04-07 17:36:00.019 [INFO ] [runtime.busevents ] - amx state updated to testString

But my rule is not triggering:
rule “Test”
when
Item amx received update testString
then
sendCommand(amx, “String received!”)
end

Seems like the String item is always in a state of ‘Null’.

If I change the rule to:
“when
Item amx received update”
Then it triggers on any string that comes in and I receive “String received!” on my tcp client.

Cheers

Dave

[vzorglub (Vincent Regaud)]

Hello,

Please use code fences when posting, please…

How to use code fences

We all have to type this content over and over and over. Here is a posting we can all point to when the topic comes up. Why use code fences? Because rules, sitemap, logs, and configs are all but unreadable when code fences are not used. When to use code fences? Whenever one is posting any sort of code, config, log, and any text where line wrapping, indentation, and using an equal spaced font makes the text more legible. How to use code fences? Use 3 backticks (```)... Or use <code>... …

Try:

rule “Test”
when
    Item amx received update "testString"
then
    amx.sendCommand(“String received!”)
end

Note that I have used the item method amx.sendCommand instead of the action sendCommand(String, String). It is recommended to use the method when you know what item to send a command to. Use the action only for some reserved cases like:

https://docs.openhab.org/configuration/rules-dsl.html#sendcommand-method-vs-action

[emaildave82]

Thanks for the reply
And the tip for the fences!

I had already tried this as well with no luck - see below. Sending in testString didn’t trigger the rule.
With the code block you posted, is there a difference with the double quotes? Some are angled and some are vertical. When I pasted yours straight into mine it changed the syntax highlighting based on the different double quotes.

rule "Test"
when
    Item amx received update "testString"
then
    amx.sendCommand("String received!")
end

I can also try this as a test to see what “String” is being held it the item “amx” after sending in a string:

rule "Test"
when
    Item amx received update
then
    amx.sendCommand(amx)
end

The log:

2018-04-07 19:41:51.752 [INFO ] [runtime.busevents             ] - amx state updated to something

2018-04-07 19:41:51.783 [ERROR] [o.o.c.s.ScriptExecutionThread ] - Error during the execution of rule 'Test': Could not invoke method: org.openhab.model.script.actions.BusEvent.sendCommand(org.openhab.core.items.Item,java.lang.String) on instance: null

Cheers

Dave

[vzorglub (Vincent Regaud)]

Try

rule "Test"
when
    Item amx received update
then
    logInfo("TEST", amx.state.toString)
    //amx.sendCommand(amx)
end

What does the log show?

[emaildave82]

@vzorglub

rule “Test”
when
Item amx received update
then
logInfo(“TEST”, amx.state.toString)
//amx.sendCommand(amx)
end

This:

2018-04-07 20:26:14.802 [INFO ] [runtime.busevents             ] - amx state updated to something

2018-04-07 20:26:16.077 [INFO ] [org.openhab.model.script.TEST ] - something

[vzorglub (Vincent Regaud)]

Ok so that works!!
Next, the double quotes denote a String

rule "Test"
when
    Item amx received update "something"
then
    logInfo("TEST", amx.state.toString)
    //amx.sendCommand(amx.state.toString)
end

[emaildave82]

@vzorglub

rule “Test”
when
Item amx received update “something”
then
logInfo(“TEST”, amx.state.toString)
//amx.sendCommand(amx.state.toString)
end

Yes, interesting that the item does actually hold the incoming string.

But still no trigger:

2018-04-07 21:11:42.524 [INFO ] [runtime.busevents             ] - amx state updated to something

Cheers

[vzorglub (Vincent Regaud)]

Ok then, workaround

rule "Test"
when
    Item amx received update
then
    logInfo("TEST", amx.state.toString)
    if (amx.state.toString == "something") {
        logInfo("TEST2", amx.state.toString)
    }
    //amx.sendCommand(amx.state.toString)
end

[emaildave82]

@vzorglub

rule “Test”
when
Item amx received update
then
logInfo(“TEST”, amx.state.toString)
if (amx.state.toString == “something”) {
logInfo(“TEST2”, amx.state.toString)
}
//amx.sendCommand(amx.state.toString)
end

Still no luck:

rule "Test"
when
    Item amx received update
then
    logInfo("TEST", amx.state.toString)
    if (amx.state.toString == "something") {
        logInfo("TEST2", amx.state.toString)
    }
    //amx.sendCommand(amx.state.toString)
end

2018-04-07 21:26:26.043 [INFO ] [runtime.busevents             ] - amx state updated to something

2018-04-07 21:26:26.064 [INFO ] [org.openhab.model.script.TEST ] - something

Cheers

[vzorglub (Vincent Regaud)]

Ok, your something string is not exactly “something” that’s why it’s doesn’t go in the if test and doesn’t trigger the rule.

Is there a trailing space or hidden character?

[emaildave82]

I wonder if there is a carriage return / line feed attached to it somehow?
This would also explain why I had no trouble doing almost exactly the same thing a few years ago with openHAB1.7.0 but with a serial connection instead of the tcp socket. I wonder if the socket is passing through the carriage return.

I’m using netcat on a MAC terminal to connect to the openHAB socket, and just typing “something” (without the quotes) and hitting enter.

I could try using packet sender on a windows machine with could probably send the string without a carriage return.

Is there a way in openhab to test the if statement with a carriage return as well? Like “something”\r ?

[vzorglub (Vincent Regaud)]

20:26:14.802 [INFO ] [runtime.busevents             ] - amx state updated to something

2018-04-07 20:26:16.077 [INFO ] [org.openhab.model.script.TEST ] - something

Is that your actual log?
If yes then there is a carriage return
How do you get the item updated?
What is the binding?

[emaildave82]

Yeah you’re right it’s putting a new line in! Yes actual log.

The binding is: https://github.com/openhab/openhab1-addons/wiki/TCP-Binding

Item:

String amx {tcp="<[10.0.1.63:*:default]"}

“How do you get the item updated?” Using a tcp client (netcat) on a MAC, typing something and hitting enter.

I have some software on windows that can send just the bytes we want and not a carriage return, I’ll try that.

And if successful, the control system I’ll be using once I set all this up can send without a carriage return as well.

Cheers

[emaildave82]

Got it to trigger by sending the update from a different tcp client (packet sender) which doesn’t add a carriage return!

2018-04-07 22:25:20.972 [INFO ] [runtime.busevents             ] - amx state updated to something
2018-04-07 22:25:20.982 [INFO ] [org.openhab.model.script.TEST ] - something
2018-04-07 22:25:21.104 [INFO ] [org.openhab.model.script.TEST2] - something

I should be right from here. Thanks heaps for all your help!

Cheers

Dave

[vzorglub (Vincent Regaud)]

You can try the trigger now

rule "Test"
when
    Item amx received update "something"
then
    logInfo("TEST", amx.state.toString)
    //amx.sendCommand(amx.state.toString)
end

[emaildave82]

Yes i have the rule triggering now, and also the sendCommand works to send a response back out over the socket.

Thanks so much for your help!

Cheers

Dave

[vzorglub (Vincent Regaud)]

That’s good…
A bit of a struggle but we got there
Please mark the thread as solved, thank you
Good luck