MQTT and {,},",: marks

Silverix · August 25, 2019, 2:10pm

MQTT is correctly configured and I don’t have any problems with connection. I have problem with sending specific commands

I have device connected over MQTT where I need to send commands which contain {, }, " and : marks. Example of command (xx is variable value):

{"init":{"type":"notification","text":"It is xx degree"}}

But when I paste it into the rule, then logs show me this:

Configuration model 'yyyyy.rules' has errors, therefore ignoring it: [31,70]: mismatched input ':' expecting '}'
[31,71]: missing ')' at '{'
[31,78]: mismatched input ':' expecting '}'
[31,93]: mismatched input ',' expecting 'end'

It looks like openhab interprets these marks like something from its function or whatever. Is there any way to bypass it?

rossko57 · August 25, 2019, 2:14pm

That format is called JSON, it is quite common.

Silverix · August 25, 2019, 2:27pm

Thank you very much. That worked perfectly

Silverix · August 25, 2019, 2:49pm

One more problem. Command works good but “xx” variable doesn’t change into number but it is sent as “xx”. How can I fix that?

'{\"init\":{\"type\":\"notification\",\"text\":\"It is xx degree\"}}'

rossko57 · August 25, 2019, 3:44pm

Dunno. Is there some reason you’re not building up your JSON string like the example you have already looked at?

+ means join strings together into one string.
"first " + "second " + "third "
Strings don’t have to be literals
“before " + myItem.state.toString + " after”

Silverix · August 25, 2019, 4:17pm

Well, this value isn’t from openhab item, but I get it from other MQTT device in this way. I tried substitute xx with device_val, but nothing changed

rule "VA"
when
    Item VA_Intent received update
then
    var String device_val = transform("JSONPATH", "$.slots[0].value.value", VA_Intent.state.toString)
    logInfo("VA device value: ", device_val)
	
	var xx = device_val

	val mqttActions = getActions("mqtt","mqtt:broker:Display_Broker")
	var temperature = '{\"init\":{\"type\":\"notification\",\"text\":\"It is xx degree\"}}'
	mqttActions.publishMQTT("xxx/xxx/xxx", temperature)
end

rossko57 · August 25, 2019, 4:36pm

Okay, here you are setting the variable temperature to a string.

Here’s another example of setting a variable to a string with some other variable in the middle.

var middle = "banana"
var everything = "apples " + middle + " oranges"

I’m not going to write this for you.

Silverix · August 25, 2019, 4:48pm

YES, THAT WORKED
’{\"init\":{\"type\":\"notification\",\"text\":\"It is ' + xx + ' degree\"}}'