Using JSON format to send data on mqtt client

[simo]

Hi i am using the library JsonparseGeneratorRK to generate the JSON format and share my data on cloud. I use jw.insertkeyvalue(“data”, “hello”) to have something like

“data”: “hello”

However I need to create a nested structure like:

“data:” {
“Sentence”: " hello"
}

How can I create a nested structure using this library? Can someonw provide an example?

[ScruffR]

I guess it should be

@simo

"data": {
"Sentence": "hello"
}

This are actually two entries

1. a key/value pair where the the key = data and the value is another JSON object
2. that object is a key/value pair that can be created the way you did but not as member of jw but as member of the object of step 1.

[simo]

void createEventPayload(int orario,  String status, double batt)
{ 
  JsonWriterStatic<256> pw;
  {
      JsonWriterAutoObject obj(&pw);
      pw.insertKeyValue("batte:",batt);
  }
  JsonWriterStatic<256> jw;
  { 
     
    JsonWriterAutoObject obj(&jw);

    jw.insertKeyValue("version", "0.0.1.0");
    jw.insertKeyValue("id", "device");
    
  }

  Particle.publish("T", jw.getBuffer(), PRIVATE);
}

This doesn’t seem to work,maybe I didn’t understand.

[ScruffR]

Sticking with one example would prevent additional confusion

As to your original request, this is how you'd do it

  JsonWriterStatic<256> jw;
  JsonWriterAutoObject obj(&jw);

  jw.insertKeyObject("data");                 // create the key/value(object)
  jw.insertKeyValue("Sentence", "hello");     // add the key/value(string) to that open object
  jw.finishObjectOrArray();                   // close the object

BTW

@simo

jw.insertKeyValue("data:",pw);

You shouldn't have a colon in your key there. While it's not forbidden, it's not best style either
The JSON string would look like this

{ "data:": {             // <-- 🤮
    "Sentence":"hello" 
  }
}