Tasmota sends me following MQTT payload for the Vindriktning-sensor: {“Time”:“2021-12-19T18:16:56”,“VINDRIKTNING”:{“PM2.5”:16}}
In my Openhab Thing I would like to parse the PM2.5 value with JSONPATH (in transformationPattern)
The expression JSONPATH:$.VINDRIKTNING.PM2.5 fails however since there is a point in the PM2.5 field.
Is there a way to escape a point-char when parsing the response with JSONPATH?
Try
JSONPATH:$.VINDRIKTNING."PM2.5"
With tasmota you can also ask it to brake out of the JSON in tasmota console enter setoption4 1
Putting double quotes around the PM2.5 part does work. This makes JSONPATH look for quotes in the name.
Invalid path ‘$.VINDRIKTNING.“PM2.5”’ in ‘{“Time”:“2021-12-19T20:44:28”,“VINDRIKTNING”:{“PM2.5”:9}}’
ps: SetOption4 seems to have no effect on the messages that Tasmota sends out on my system (10.1.0)
try to use
$[VINDRIKTNING][PM2.5]
because the documentaion siad JSONPath is based ib GitHub - json-path/JsonPath: Java JsonPath implementation
I think you need the ` in bracket notation
$['VINDRIKTNING']['PM2.5']
Perfect. This notation work without any problem. Thank you very much.
Hi,
I also just try to add the Vindriktning sensor to OH.
Flashed, Tasmota works fine.
I also add a OH item in the rules, after saving the rules (with the working jsonpath -part, thx to denominator!), I get one line:
2022-03-20 14:28:00.397 [vent.ItemStateChangedEvent] - Climate_Vind_01_particles changed from NULL to 6
=> So, working correct.
“6” is the correct value, see also in the Tasmota frontend.
But (surely) stupid question (nearly one year nothing done with MQTT and OH),
how I will get updates?
Have I to create a “trigger”, can this be done on the Tasmota-console (send every minute a mqtt-message out) or in OH ?
A default installation of Tasmota will publish an update on the tele topic every 300 seconds (5 minutes).
Oh yes, I should wait 
Can I change this, using the command prompt from Tasmota ?
Yes
teleperiod X
Where X is the number of seconds between updates.