Hi all, pretty new to OpenHAB.
My implementation uses JSON structures to communicate via an MQTT broker (mosquitto).
I can send a JSON structure from my device to OpenHAB and extract the JSON using the jsonpath transform. What I can’t manage to do is populate a JSON structure to be sent via MQTT to my device to control it.
Example: I want to switch on a switch implemented on some hardware using the topic “controller-out/5/cmd/” and as message body the JSON string:
{“port”:0, // This indicates on the receiver which “relay” to target. So for each item it will be a unique number.
“cmd”:1, // This indicates to my controller that it is a command not a status update or internal message
"type":0, // This indicates the type of switch/device being targeted, not important
"value":0} // This is the physical command. In this case 0 is ON and 1 is OFF
I have several items defined in a group:
Group gCliviaIrrigation "Clivia irrigation zones" <rain>
Switch Switch_Zone1 "Irrigation Zone1" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
Switch Switch_Zone2 "Irrigation Zone2" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
Switch Switch_Zone3 "Irrigation Zone3" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
Switch Switch_Zone4 "Irrigation Zone4" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
Switch Switch_Zone5 "Irrigation Zone5" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
Switch Switch_Zone6 "Irrigation Zone6" <water> (gCliviaIrrigation) { mqtt=">[mosquitto:controller-out/5/cmd/:command:*:xxxxx]" }
So there are two problems really. The first is to set the “port” in the JSON to a unique number that gets derived from the switch being toggled. The second problem is compiling the JSON structure oand getting MQTT to send it. I have looked at having a rule to trigger but I have no idea how to “pass” data. I am struggling not to think in C !
