switching from DynamicJsonDocument to JsonDocument

[MHz000]

I use an esp32doit-devkit-v1 with the bblanchon/ArduinoJson@^7.0.3 library. If it helps, I'll be happy to send the source code too When I switch from DynamicJsonDocument to JsonDocument I get the following error messages:

src\main.cpp:147:24: required from here .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:40:3: error: no type named 'type' in 'struct ArduinoJson::V703PB2::detail::enable_if<false ,void>' .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:33:3: note: candidate: ArduinoJson::V703PB2::JsonDocument::JsonDocument(ArduinoJson::V703PB2::JsonDocument&&) JsonDocument(JsonDocument&& src) ^ .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:33:3: note: no known conversion for argument 1 from 'int' to 'ArduinoJson::V703PB2::JsonDocument&&' .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:28:3: note: candidate: ArduinoJson::V703PB2::JsonDocument::JsonDocument(const ArduinoJson::V703PB2::JsonDocument& ) JsonDocument(const JsonDocument& src) : JsonDocument(src.allocator()) { ^ .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:28:3: note: no known conversion for argument 1 from 'int' to 'const ArduinoJson::V703PB2::JsonDocument&' .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:24:12: note: candidate: ArduinoJson::V703PB2::JsonDocument::JsonDocument(ArduinoJson::V703PB2::Allocator ) explicit JsonDocument(Allocator alloc = detail::DefaultAllocator::instance()) ^ .pio\libdeps\esp32doit-devkit-v1\ArduinoJson\src/ArduinoJson/Document/JsonDocument.hpp:24:12: note: conversion of argument 1 would be ill-formed: src\main.cpp:147:24: error: invalid conversion from 'int' to 'ArduinoJson::V703PB2::Allocator*' [-fpermissive] JsonDocument doc(1536); // Dynamic JSON? ^ *** [.pio\build\esp32doit-devkit-v1\src\main.cpp.o] Error 1

[bblanchon]

Hi @MHz000,

When you get an error when compiling a C++ program, you must look at the first error in the compiler output (which might not be the order shown in the IDE). In your case, the first error is:

error: no matching function for call to 'ArduinoJson::V703PB2::JsonDocument::JsonDocument(int)'

This error tells that JsonDocument has no constructor with an int parameter. You can fix it like so:

- JsonDocument doc(1536);
+ JsonDocument doc;

If you think a document was unclear and led you to make this error, please let me know so I can fix it immediately.

Best regards, Benoit

[MHz000]

BINGO! Hi Benoit, your tip solved my problem straight away, thank you!; You will have seen at first glance that I am not an experienced C++ programmer. So I dare to ask you another question. In my program I receive an extensive JSON file see appendix, which I use to decode by if (httpCode == HTTP_CODE_OK || httpCode == HTTP_CODE_MOVED_PERMANENTLY) { String payload = https.getString(); Serial.println("GOT API RESPONSE"); decodeJsonPayload(payload.c_str()); take apart void decodeJsonPayload(const char* payload) { JsonDocument doc; DeserializationError error = deserializeJson(doc, payload); if (error) { ... </code) My problem: I only get the last part of the deserialization_ed payload as a result. If it helps with the solution I would be happy to send the entire source code# Thank you Joschen JSON-data.txt

[bblanchon]

What does the ArduinoJson Troubleshooter say?

[MHz000]

Hi Beniot thanks to your hint "You can fix it like this:

• JsonDocument doc(1536);
• JsonDocument doc;" I can now use the JSON document without any problems. You can find a JSON example in the appendix. My question boils down to this: How can I access the individual sub-documents {timestamp...}, {timestamp...},... separately? Yes, it is possible to use String operators to do this. This is tedious, error-prone and boring. Is there a more elegant way. Thank you for your great library and support Joschen JSON-data.txt

[bblanchon]

Hi Joschen,

You can find extensive documentation at https://arduinojson.org/ Let me know if you have any issues.

Best regards, Benoit