Publish data from openhab in json format

mmj6 · August 27, 2018, 7:14am

I created rules to publish data in json format, I’m not really sure about the format of the rule… So my rules has errors, any help on what am I doing wrong…?

The format in which I want the data is

{
    "reference":"1234",
    "confirmed": true,
    "fPort": 10,
    "object": {
        "sep": 255,
        "control1": 1
  
    }
}

the control1 would display 1 or 0 depending on the status of mylight

The sitemap and items file

Switch item=mylight label="Light1"

Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">[mosquitto:application/2/node/00000000000000:command:ON:1],>[mosquitto:application/2/node/00000000000000:command:OFF:0]"}

The rule I wrote has errors…

rule "mqtt update"
when
    Item  mylight received update
then
    mylight.SendCommand("{\"fport\":\"10\",\"object"\"control1\":\"mylight\"}")
    logInfo("Test2","running")
end

vzorglub · August 27, 2018, 9:47am

So you need to send the json string to the light?
You might be able to achieve that by using the map transform

Create a mylight.map file in the transform folder with the following content:

ON={"reference":"1234","confirmed": true,"fPort": 10,"object": {"sep": 255,"control1": 1}}
OFF={"reference":"1234","confirmed": true,"fPort": 10,"object": {"sep": 255,"control1": 0}}

Change your item definition as follow:

Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">mosquitto:application/2/node/00000000000000:command:*:MAP(mylight.map)]"}

If it doesn’t work you may need to ‘escape’ the double quotes in the .map file but it should work as is as specified here:

https://docs.oracle.com/javase/8/docs/api/java/util/Properties.html#load-java.io.Reader-

mmj6 · August 27, 2018, 10:25am

oh… Never thought about transforms . Yeah I need to send the status of mylight to mqtt broker.
I did like you said but it is not working… I’m sorry but what exactly do you mean by escape double quotes

I read through the link you gave, but I really did not get it.

vzorglub · August 27, 2018, 11:10am

OK, what exactly do you need to send to the broker?

mmj6 · August 27, 2018, 11:20am

I need to send the following data,

{
“reference”:“1234”,
“confirmed”: true,
“fPort”: 10,
“object”: {
“sep”: 255,
“control1”: 1

}

control1 gives the status of mylight 1 if its ON, 0 if it’s OFF

vzorglub · August 27, 2018, 11:23am

Ok, do you have an MQTT monitor like mqtt.fx?
Can you check that the messages are being sent?

mmj6 · August 28, 2018, 5:26am

I am able send it to mqtt lens, but that’s only 1 and 0. I need to send it with json payload… I tried doing so by writing rules, but like I said my rules have errors but I’m not sure what errors…

pacive · August 28, 2018, 5:34am

It errors because you try to send a string to a switch item. A switch item only accepts ON and OFF as commands. If you want to send something else to the actual device you need to specify that in the item definition, with a transform, like @vzorglub suggested. An alternative is to use the mqtt action to publish directly from the rule instead.

mmj6 · August 28, 2018, 5:42am

I’m trying to send to mqtt broker…

Mqtt action I’ll try with that.

vzorglub · August 28, 2018, 9:12am

@mmj6
It should work as I set it up
What does the openhab.log show when you change the switch on the UI?
Is the MAP transform installed?
Is the mylight.map located in the /etc/openhab2/conf/transform folder?
Can you publish you code? rules, items and map file as they are, please?
Thanks

mmj6 · August 28, 2018, 10:14am

logs

2018-08-28 14:52:40.882 [INFO ] [io.openhabcloud.internal.CloudClient] - Disconnected from the openHAB Cloud service (UUID = df470386-e60e-4e6b-81bd-05f768013f55, base URL = http://localhost:8080)
2018-08-28 15:35:12.278 [INFO ] [io.openhabcloud.internal.CloudClient] - Connected to the openHAB Cloud service (UUID = df470386-e60e-4e6b-81bd-05f768013f55, base URL = http://localhost:8080)
2018-08-28 15:38:22.725 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'
2018-08-28 15:38:22.744 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'```

Transform

```php
ON={"reference":"1234","confirmed": true,"fPort": 10,"object": {"sep": 255,"control1": 1}}
OFF={"reference":"1234","confirmed": true,"fPort": 10,"object": {"sep": 255,"control1": 0}}

The mylight.map file is in C:\openHAB2\conf\transform
I deleted the rules I wrote

items

Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:*:MAP(mylight.map)]"}
Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:ON:1],>[mosquitto:application/2/node/0000000000000013/tx:command:OFF:0]"}

Although there are no errors this data is not getting sent to mqtt broker

vzorglub · August 28, 2018, 10:21am

You have two items named the same. That won’t work.
Rename the second one and
And add a space after the { abd before the } it helps the parser sometimes

Switch mylight "light1" <slider> ["Switchable"]  { mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:*:MAP(mylight.map)]" }
Switch mylight2 "light2" <slider> ["Switchable"]  { mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:*:default] }

mmj6 · August 28, 2018, 10:53am

I deleted one of it.
now my items file has only this

Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:*:MAP(mylight.map)]"}

logs

2018-08-28 16:16:11.665 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'
2018-08-28 16:17:29.945 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'
2018-08-28 16:17:29.961 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'
2018-08-28 16:22:52.543 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'
2018-08-28 16:22:52.556 [INFO ] [el.core.internal.ModelRepositoryImpl] - Refreshing model 'b.items'

vzorglub · August 28, 2018, 11:15am

What does the both logs show when you action the switch in the sitemap?

mmj6 · August 28, 2018, 11:41am

openhab logs shows only refreshing model b.items,

event logs

2018-08-28 16:53:11.934 [ome.event.ItemCommandEvent] - Item 'mylight' received command ON
2018-08-28 16:53:11.936 [vent.ItemStateChangedEvent] - mylight changed from OFF to ON
2018-08-28 16:53:12.094 [ome.event.ItemCommandEvent] - Item 'mylight' received command OFF
2018-08-28 16:53:12.097 [vent.ItemStateChangedEvent] - mylight changed from ON to OFF

vzorglub · August 28, 2018, 11:50am

Ok and what do you see on mqtt lens when you action the switch?

mmj6 · August 29, 2018, 3:53am

Right now nothing…

vzorglub · August 29, 2018, 7:44am

Change the item to:

Switch mylight "light1" <slider> ["Switchable"]  {mqtt=">[mosquitto:application/2/node/0000000000000013/tx:command:*:default]"}

What do you get it MQTT lens?

info2 · March 31, 2019, 11:11am

Sorry for bringing this from the dead just wanted to mention that this in my things/mqtt.things saved me

   Thing mqtt:topic:LEDStrip_LivingRoom_Power "LEDStrip_LivingRoom_Power" {
     Channels:
         Type switch : switch "LEDStrip_LivingRoom_Power Switch" [
           commandTopic="hestia/livingroom/LED/set",
           on="{'state':'ON'}",
           off="{'state':'OFF'}"
         ]
   }

mixed double and single quotes right in the thing definition until mapping for outgoing MQTT (2.5) is relased. Currently on 2.4 and works fine.