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How to get values from a Json message
#1
Dear,

Is there any example of how to configure the MQTT variables for data viewing?
The topic I'm reading returns the following JSON:


{
  "results" : [ {
    "name" : "Temperatura",
    "value" : 24,
    "timestamp" : 1653760447,
    "description" : "",
    "unit" : "°C"
  } ]
}


How do I configure the variable to read the temperature value?
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#2
Hi,
I am sorry, I don't have a tutorial yet.
It is very easy to do it.

I have uploaded your json text to the hiveMQ broker to the topic: virtuino_test
1. Create a new project
2. Add the default Virtuino MQTT connection to the broker HiveMQ
3. Enter the sub topic: virtuino_test
4. Go to the broker variables. Select the variable V0. Select as sub topic the "virtuino_test" topic
5. On the field "Value Json path" enter the follow path
results[0]/name

Insert a "Value display" to read the V0
Then connect and check the results

The results[0] returns the first json item of the results array
The name returns the value of the json field name
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#3
Photo 
Hi,
I have a similar problem. How to get value from array?
{
  "dio" : {
    "do" : [ 0, 1, 0, 0, 0, 1, 0 ],
    "ro" : [ 0, 0, 0, 0, 0, 1, 0 ],
    "di" : [ 0, 0, 1, 0, 1, 0, 0, 0 ]
  }
}


I did this: dio/ro[0] (Error:No value for ro[0])
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#4
Hi,

I have check with the latest version 0.1.0

It works fine!
Check for errors in Json message

I have created a video about it

https://youtu.be/ukBEXHhDvF4
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#5
Hi iliaslamprou,
Thank you for the video. I forgot to say that I tried to do this in Virtuino MQTT in 1.0.36
Now I'll try to install Virtuino IoT.
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