Parse JSON to use in HabPanel

Setup, Configuration and Use Items & Sitemaps
, ,
1

Hello,

I’m still learning to do openhab. I’m creating an custom widget to control an Hue group. I would like to set the scene to the group. I’m able to do this by a rule which uses sendHttpPutRequest to switch to the scene, but currently the scene ID is fixed in the rule. I would like to enumurate the scene Ids from the Hue bridge, and use them in my Openhab widget.

I can get them in a JSON response from:
http://api//scenes

Format:

{"CchzXmkNLypkgtq":{"name":"Arctische dageraad","lights":["3","4","5","6","7","8","9","12","13"],"owner":"none","recycle":false,"locked":false,"appdata":{"version":1,"data":"a9iwJ_r01_d17"},"picture":"","lastupdated":"2017-12-05T16:43:58","version":2},
"IQzfjQpsbNE-VGq":{"name":"Savanne zonsondergang","lights":["3","4","5","6","7","8","9","12","13"],"owner":"none","recycle":false,"locked":false,"appdata":{"version":1,"data":"JvkFV_r01_d15"},"picture":"","lastupdated":"2017-12-10T14:07:54","version":2}}

It’s possible to parse JSON in an item, but I can only parse a single string and not an array.

What would be my options here?

Any help is very welcome, thanks!
Bastiaan

2

The best way is use a controller, but since you’re making a custom widget, I assume you want to make this available for everyone? Controller-less code is better so users wont have to mess with code. So, to solve your issue:

  1. Use JsonPath to parse your data and extract this part
    ["3","4","5","6","7","8","9","12","13"]

  2. Save that onto an item, for example,

    String sceneArray1

  3. The ‘hackish’ part

    <div ng-repeat="scene in (itemValue('sceneArray1') || '').split('[')[1].split(']')[0].split(',') track by $index">
    Scene: {{scene.replace('"','').replace('"','')}}
</div>

image

1 Like
3

Assuming you’ve got your JSON as posted above in an item named “Hue_Scenes” you can use this:

<div ng-repeat="json in [itemState('Hue_Scenes')]">
  <div ng-repeat="(id, scene) in $eval(json)">
    <button class="btn btn-default">{{scene.name}}</button>
    <br />
  </div>
</div>

This gives you:
image

The first ng-repeat on a singleton array is a trick to avoid “infinite digest” errors.

4

Thank you for your replies. This two approaches should get me started. Thanks for this!

I’m busy with JSONPath, and it doens not allow me to get key and value. I want to display the scene names in Habpanel, but need the corresponding uid in order to tell the HUE api to switch to this scene. Any idea’s on this?

5

Shouldn’t uid be unique and a known value?

6

If I want to make it completely dynamic, so we can add scene’s thru the HUE app, I do not know the uid’s in advance.

uid = “CchzXmkNLypkgtq” / name = "Arctische dageraad"
uid = “IQzfjQpsbNE-VGq” / name = “Savanne zonsondergang”

I could create two strings, one getting the uid’s, and the other the names. The order should be equal. And then build it with angular which would result in:

<select name="selected-uid">
<option name="CchzXmkNLypkgtq">Arctische dageraad</option>
<option name="IQzfjQpsbNE-VGq">Savanne zonsondergang</option>
....
</select>

Would that be possible?

7

I ended up defining the scene id’s in the HabPanel widget. When the select is changed, a rule is triggered and changes the scene aganst the HUE API.

rule "Hue Scene Select - Woonkamer"
when
	Item Hue_Scene_Woonkamer changed
then
	sendHttpPutRequest("http://192.168.1.222/api/<yourusername>/groups/1/action", "application/json", '{"scene": "'+ Hue_Scene_Woonkamer.state +'"}')
	logInfo("Hue Woonkamer", "Hue Scene Woonkamer changed to " + Hue_Scene_Woonkamer.state)
	
	// Change brightness to current value (not one stored in scene)
	createTimer(now.plusSeconds(3), [|
		var int brightness = Hue_Brightness_Woonkamer.state
		sendCommand(Hue_Brightness_Woonkamer, brightness)
		logInfo("Hue Woonkamer", "Hue Scene Woonkamer brightness changed to " + Hue_Brightness_Woonkamer.state)
	])
end

rule "Hue Brightness - Woonkamer"
when
	Item Hue_Brightness_Woonkamer changed
then
	sendHttpPutRequest("http://192.168.1.222/api/<yourusername>/groups/1/action", "application/json", '{"bri": '+ Hue_Brightness_Woonkamer.state +'}')
	logInfo("Hue Woonkamer", "Hue Brightness Woonkamer changed to " + Hue_Brightness_Woonkamer.state)
end