ESP8266 array of jsons

[KristianDukov]

Hello All,

I am having the following code where I create a JSON every couple of seconds with some measurements:

char buffer[256]; root["reps"] = n; root["power"] = powerContract; root["weight"] = weight; root["set"] = s; root["contract"] = contract; root["acc"] = "asd"; root["sensor"] = machine; root.printTo(buffer); String Json = String(buffer); webSocket.broadcastTXT(Json);

Sending via WS works fine and the message is readable.

What I am trying to do is to create a list of all measurements I guess as an array so I can upload it via API. I tried with

JsonArray& array = jsonBuffer2.createArray(); JsonObject& buffer = array.createNestedObject();
but I guess I am missing something. Can somebody help?

THank you in advance

[bblanchon]

Hi @KristianDukov,

It seems that you are in the right direction.
I wouldn't call the object buffer, but that should be a problem.
What's wrong with JsonArray::createNestedObject()?

Regards,
Benoit

[KristianDukov]

Hello,

I reviewed the output of JsonArray::createNestedObject() and I don't think it will work for me. I was thinking more to get an output such as:
'
{'sensor': 1, 'rep': 1}, {'sensor': 1, 'rep': 2}, '
So I ca post it to an API.

I will review what was the error I was getting tonight

Thank you!
Kris

[KristianDukov]

I think it worked out with

const char* jsonDuplicate = jsonBuffer.strdup(Json); array.add(jsonBuffer.parseObject(jsonDuplicate)); array.printTo(Serial);

But how I can be sure that it will be recognized as separate JSONs? Does anybody know a website that I can post and test it?

[bblanchon]

Hi @KristianDukov,

Usually, a JSON API that requires an array expects something like:

[{"sensor": 1,"rep":1},{"sensor":1,"rep":2}]

...because that is how the JSON specification defines an array.
This is the kind of output you'll get if you call JsonArray::printTo().

On the other hand, if you don't want the brackets at the beginning and the end, why are you using a JsonArray?
Instead, you could simply serialize each JsonObject and insert a comma between them.

obj1.printTo(Serial);
Serial.print(",");
obj2.printTo(Serial);

Regards,
Benoit