ArduinoJson 6.18.1

Changes

• Fixed support for volatile float and volatile double (issue #1557)
• Fixed error [Pe070]: incomplete type is not allowed on IAR (issue #1560)
• Fixed serializeJson(doc, String) when allocation fails (issue #1572)
• Fixed clang-tidy warnings (issue #1574, PR #1577 by @armandas)
• Added fake class InvalidConversion<T1,T2> to easily identify invalid conversions (issue #1585)
• Added support for std::string_view (issue #1578, PR #1554 by @0xFEEDC0DE64)
• Fixed warning definition of implicit copy constructor for 'MsgPackDeserializer' is deprecated because it has a user-declared copy assignment operator
• Added JsonArray::clear() (issue #1597)
• Fixed JsonVariant::as<unsigned>() (issue #1601)
• Added support for ESP-IDF component build (PR #1562 by @qt1, PR #1599 by @andreaskuster)

View version history

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.18.0

📰 Read the complete article on arduinojson.org

Changes since 6.17.3

• Added support for custom converters (issue #687)
• Added support for Printable (issue #1444)
• Removed support for char values, see below (issue #1498)
• deserializeJson() leaves \uXXXX unchanged instead of returning NotSupported
• deserializeMsgPack() inserts null instead of returning NotSupported
• Removed DeserializationError::NotSupported
• Added JsonVariant::is<JsonArrayConst/JsonObjectConst>() (issue #1412)
• Added JsonVariant::is<JsonVariant/JsonVariantConst>() (issue #1412)
• Changed JsonVariantConst::is<JsonArray/JsonObject>() to return false (issue #1412)
• Simplified JsonVariant::as<T>() to always return T (see below)
• Updated folders list in .mbedignore (PR #1515 by @AGlass0fMilk)
• Fixed member-call-on-null-pointer in getMember() when array is empty
• serializeMsgPack(doc, buffer, size) doesn't add null-terminator anymore (issue #1545)
• serializeJson(doc, buffer, size) adds null-terminator only if there is enough room
• PlatformIO: set build.libArchive to false (PR #1550 by @askreet)

BREAKING CHANGES

Support for char removed

We cannot cast a JsonVariant to a char anymore, so the following will break:

char age = doc["age"];  //  error: no matching function for call to 'variantAs(VariantData*&)'

Instead, you must use another integral type, such as int8_t:

int8_t age = doc["age"];  // OK

Similarly, we cannot assign from a char anymore, so the following will break:

char age;
doc["age"] = age;  // error: no matching function for call to 'VariantRef::set(const char&)'

Instead, you must use another integral type, such as int8_t:

int8_t age;
doc["age"] = age;  // OK

A deprecation warning with the message "Support for char is deprecated, use int8_t or uint8_t instead" was added to allow a smooth transition.

as<T>() always returns T

Previously, JsonVariant::as<T>() could return a type different from T.
The most common example is as<char*>() that returned a const char*.
While this feature simplified a few use cases, it was confusing and complicated the
implementation of custom converters.

Starting from this version, as<T> doesn't try to auto-correct the return type and always return T,
which means that you cannot write this anymore:

Serial.println(doc["sensor"].as<char*>());  // error: invalid conversion from 'const char*' to 'char*' [-fpermissive]

Instead, you must write:

Serial.println(doc["sensor"].as<const char*>());  // OK

A deprecation warning with the message "Replace as<char*>() with as<const char*>()" was added to allow a smooth transition.

DeserializationError::NotSupported removed

On a different topic, DeserializationError::NotSupported has been removed.
Instead of returning this error:

• deserializeJson() leaves \uXXXX unchanged (only when ARDUINOJSON_DECODE_UNICODE is 0)
• deserializeMsgPack() replaces unsupported values with nulls

Const-aware is<T>()

Lastly, a very minor change concerns JsonVariantConst::is<T>().
It used to return true for JsonArray and JsonOject, but now it returns false.
Instead, you must use JsonArrayConst and JsonObjectConst.

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.18.0.h put it in your project folder
3. Download ArduinoJson-v6.18.0.zip and extract it into your libraries folder

Note: ArduinoJson-v6.18.0.h and ArduinoJson-v6.18.0.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.17.3

Changes since 6.17.2

• Made JsonDocument's destructor protected (issue #1480)
• Added missing calls to client.stop() in JsonHttpClient.ino (issue #1485)
• Fixed error expected ')' before 'char' when isdigit() is a macro (issue #1487)
• Fixed error definition of implicit copy constructor is deprecated on Clang 10
• PlatformIO: set framework compatibility to * (PR #1490 by @maxgerhardt)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.17.3.h put it in your project folder
3. Download ArduinoJson-v6.17.3.zip and extract it into your libraries folder

Note: ArduinoJson-v6.17.3.h and ArduinoJson-v6.17.3.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.17.2

📰 Read the complete article on arduinojson.org

Changes since 6.17.1

• Fixed invalid conversion error in operator|(JsonVariant, char*) (issue #1432)
• Changed the default value of ARDUINOJSON_ENABLE_PROGMEM (issue #1433).
  It now checks that the pgm_read_XXX macros are defined before enabling PROGMEM.

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.17.2.h put it in your project folder
3. Download ArduinoJson-v6.17.2.zip and extract it into you libraries folder

Note: ArduinoJson-v6.17.2.h and ArduinoJson-v6.17.2.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.17.1

📰 Read the complete article on arduinojson.org

Changes since 6.17.0

• Fixed error ambiguous overload for 'operator|' (issue #1411)
• Fixed operator|(MemberProxy, JsonObject) (issue #1415)
• Allowed more than 32767 values in non-embedded mode (issue #1414)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.17.1.h put it in your project folder
3. Download ArduinoJson-v6.17.1.zip and extract it into you libraries folder

Note: ArduinoJson-v6.17.1.h and ArduinoJson-v6.17.1.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.17.0

📰 Read the complete article on arduinojson.org

Changes since 6.16.1

• Added a build failure when nullptr is defined as a macro (issue #1355)
• Added JsonDocument::overflowed() which tells if the memory pool was too small (issue #1358)
• Added DeserializationError::EmptyInput which tells if the input was empty
• Added DeserializationError::f_str() which returns a const __FlashStringHelper* (issue #846)
• Added operator|(JsonVariantConst, JsonVariantConst)
• Added filtering for MessagePack (issue #1298, PR #1394 by Luca Passarella)
• Moved float convertion tables to PROGMEM
• Fixed JsonVariant::set((char*)0) which returned false instead of true (issue #1368)
• Fixed error No such file or directory #include <WString.h> (issue #1381)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.17.0.h put it in your project folder
3. Download ArduinoJson-v6.17.0.zip and extract it in you libraries folder

Note: ArduinoJson-v6.17.0.h and ArduinoJson-v6.17.0.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.16.1

📰 Read the complete article on arduinojson.org

Changes since 6.16.0

• Fixed deserializeJson() that stopped reading after {} (issue #1335)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.16.1.h put it in your project folder
3. Download ArduinoJson-v6.16.1.zip and extract it in you libraries folder

Note: ArduinoJson-v6.16.1.h and ArduinoJson-v6.16.1.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.16.0

📰 Read the complete article on arduinojson.org

Changes since 6.15.2

• Added comparisons (>, >=, ==, !=, <, and <=) between JsonVariants
• Added string deduplication (issue #1303)
• Added JsonString::operator!=
• Set ARDUINOJSON_DECODE_UNICODE to 1 by default
• Fixed copyArray() not working with String, ElementProxy, and MemberProxy
• Fixed error getOrAddElement is not a member of ElementProxy (issue #1311)
• Fixed excessive stack usage when compiled with -Og (issues #1210 and #1314)
• Fixed Warning[Pa093]: implicit conversion from floating point to integer on IAR compiler (PR #1328 by @stawiski)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.16.0.h put it in your project folder
3. Download ArduinoJson-v6.16.0.zip and extract it in you libraries folder

Note: ArduinoJson-v6.16.0.h and ArduinoJson-v6.16.0.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.15.2

Changes since 6.15.1

• CMake: don't build tests when imported in another project
• CMake: made project arch-independent
• Visual Studio: fixed error C2766 with flag /Zc:__cplusplus (issue #1250)
• Added support for JsonDocument to copyArray() (issue #1255)
• Added support for enums in as<T>() and is<T>() (issue #1256)
• Added JsonVariant as an input type for deserializeXxx()
  For example, you can do: deserializeJson(doc2, doc1["payload"])
• Break the build if using 64-bit integers with ARDUINOJSON_USE_LONG_LONG==0

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager or equivalent
2. Download ArduinoJson-v6.15.2.h put it in your project folder
3. Download ArduinoJson-v6.15.2.zip and extract it in you libraries folder

Note: ArduinoJson-v6.15.2.h and ArduinoJson-v6.15.2.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample

ArduinoJson 6.15.1

Changes since 6.15.0

• Fixed "maybe-uninitialized" warning (issue #1217)
• Fixed "statement is unreachable" warning on IAR (issue #1233)
• Fixed "pointless integer comparison" warning on IAR (issue #1233)
• Added CMake "install" target (issue #1209)
• Disabled alignment on AVR (issue #1231)

View version history

How to install

There are several ways to install ArduinoJson, from simpler to more complex:

1. Use the Arduino Library Manager
2. Download ArduinoJson-v6.15.1.h put it in your project folder
3. Download ArduinoJson-v6.15.1.zip and extract it in you libraries folder

Note: ArduinoJson-v6.15.1.h and ArduinoJson-v6.15.1.hpp are almost identical; the difference is that the .hpp keeps everything in the ArduinoJson namespace.

Try online

• JsonGeneratorExample
• JsonParserExample
• MsgPackParserExample