Jsonpath and Regex-Filter in 2.4

Setup, Configuration and Use Items & Sitemaps
1

Hi all
In the old MQTT-Binding I configured an item
Number itemname “label [%.1f °C]” {mqtt="<[broker:RTL_433/JSON:state:JSONPATH($.temperature_C):.“sid” \: 10,.]"}
To get the temperatur from the following mqtt payload:
{“time” : “2018-12-18 06:14:46”, “brand” : “OS”, “model” : “OSv1 Temperature Sensor”, “sid” : 10, “channel” : 2, “battery” : “OK”, “temperature_C” : 18.800}
In 2.4 I configured this Item with paperUI. JSONPath transformation works but only without appending the regex-filter.
Can anybody help me with this?

1 Like
2

I solved this like this:

Thing mqtt:topic:rtl433 "Rtl433"  (mqtt:broker:mosquitto) {
    Channels:
        Type string : raw  "Raw"       [stateTopic="devices/rtl433"] 
        Type number : tuin "Tuin temp" [stateTopic="devices/rtl433", transformationPattern="JSONPATH:$..[?(@.model =~ /LaCrosse.*/i )].temperature_C"]

        Type number : other "Tuin other"       [stateTopic="devices/rtl433", transformationPattern="JSONPATH:$..[?(@.model =~ /AlectoV1.*/i )].temperature_C"]
        Type number : humidity "Tuin humidity" [stateTopic="devices/rtl433", transformationPattern="JSONPATH:$..[?(@.model =~ /AlectoV1.*/i )].humidity"]
}

The jsonpath ($…[?(@.model =~ /LaCrosse.*/i )].temperature_C) translates to look for an object with a model equal to LaCrosse and from that object return the temperature_C. In case the model is not equal this will return null and creates a log warning like this;

[WARN ] [eneric.internal.generic.ChannelState] - Incoming payload 'NULL' not supported by type 'NumberValue'

If that bothers you you can suppress that by changing the log level for that class in the karaf console.

2 Likes
3

Thank you very much, works like a charm

4

Have a similar problem: With the old mqtt binding I receive values from an Emonhub node. The Emonhub send its data as a payload with the following (example) format ‘7,3136,10,235.4,0,13,0’. In the item declaration I filtered the payload with a regex expression for each value. For the first value (a 7 in this case) the regex looks like this: mqtt="<[mosquitto:emonhub/rx/10/values:state:REGEX((.),.,.,.,.,.,.*)]".
How can I do a similar transform with the new 2.4 binding?

5

I didn’t test it, but I found, that Regex-Transformation was not installed under Add-ons. I suppose this was the cause for my problem.

6

I checked my system and Regex 2.4.0 addon is installed and started. So, that was not the problem.

7

If you monitor the battery state “OK”,“NOK” then the ‘NULL’ will rewrite the correct state :frowning:

Did you resolve the NULL warning?