Code is working on Wandbox but not working on Hardware

[apanasara]

I am using NodeMCU 1.0 & 0.9 with PlatformIO.

After migrating to ArduinoJson v6.11.0, I am facing problem for parsing nesting Arrays.

Below Same code is working on Wandbox but not working on Hardware

Code on Arduino WandBox

#include <iostream>
#include "ArduinoJson.h"

int main() {

 char array[] = "[[1,2],[2,3]]";

DynamicJsonDocument doc(1024);
deserializeJson(doc, array);

  // Print values.
  std::cout << doc<< std::endl; // This prints: [[1,2],[2,3]]
  std::cout << doc[0] << std::endl; // This prints: [1,2]

  return 0;
}

Code on Arduino PlatfiormIO NodeMCU

char array[] = "[[1,2],[2,3]]";

DynamicJsonDocument doc(1024);
deserializeJson(doc, array);

serializeJson(doc, Serial);
// This prints:
// "[[1,2],[2,3]]"

serializeJson(doc[0], Serial);
// This prints:
// null

JsonArray data = doc.as<JsonArray>();
serializeJson(data, Serial);
// This prints:
// null

[apanasara]

I read documentation of v6 in which I found that ESP8266 is not in list of supported hardware

So I will degrade library from v6 to back in v5 (v5 tested & supporting to ESP8266)

[bblanchon]

Hi @apanasara,

ArduinoJson v6 supports ESP8266, and the program above runs as expected on my Adafruit Huzzah.

Please double check.

Best Regards, Benoit

[apanasara]

Nested arrays used

Compilation message nodemcuv2 (platform: espressif8266; board: nodemcuv2; framework: arduino) CONFIGURATION: https://docs.platformio.org/page/boards/espressif8266/nodemcuv2.html PLATFORM: Espressif 8266 > NodeMCU 1.0 (ESP-12E Module) HARDWARE: ESP8266 80MHz 80KB RAM (4MB Flash) Library Dependency Finder -> http://bit.ly/configure-pio-ldf LDF MODES: FINDER(chain) COMPATIBILITY(soft)

Screenshot

[apanasara]

Error-Observation

I tried following mechanism to deserialize & found following solution. (don't know exact reason, you can share if know)

Code Block

int Response(char *topic, const char *msg_buf)
{
  Serial.print("in Response Block : ");
  Serial.println(msg_buf);
  StaticJsonDocument<2048> req;
  DeserializationError err = deserializeJson(req, msg_buf, DeserializationOption::NestingLimit(4));

/*------following re-deserilization worked for me------*/
  err = deserializeJson(req, req.as<const char*>(), DeserializationOption::NestingLimit(4));

Output

[bblanchon]

Hi @apanasara,

I'm gald you found a solution. This article may be relevant: Why is the input modified?

Best Regards, Benoit