MessagePack Support?

[mahmed8003]

Is it possible to have MessagePack support.
Instead of printing JSON string to buffer using this method
size_t prettyPrintTo(char *buffer, size_t bufferSize)
can we have another method like
size_t msgPackPrintTo(char *buffer, size_t bufferSize)

Use case:

• Final buffer size could be smaller and it can reduce the network data usage where sensor sending lot of data in json string.
• Instead of storing plain JSON string to SPIFFS we can store small msgPack buffer. It will reduce file size.

[bblanchon]

This sound like a good idea, and that's 100% aligned with the philosophy of ArduinoJson.
However, I'm afraid most users would prefer the official implementation instead of ArduinoJson...

Also, it looks like there will be a lot of testing, so I'd like to see how much traction this feature gets before writing a lot of code.

Let's see how many upvotes 👍 (or downvotes 👎) we get on this feature request.

[heman4t]

When its about...

Final buffer size could be smaller and it can reduce the network data usage where sensor sending lot of data in json string.

I upvote. For me size is equally important to performance in micro controllers.

[sticilface]

I'd be keen on this. reducing the buffer size is great from my end! limited ram and all..

[cosmikwolf]

upvote. I want to use arduino JSON to store data on local storage, but it is not efficiently packed. Would love a way to reduce the output size. Even just storing variables in their hex format would be good.

[cosmikwolf]

ArduinoJSON is miles ahead of the msgPack arduino implementation, would way rather use ArduinoJSON for this purpose.

[bblanchon]

Branch 5.8.x seems to be quite stable now.
I'll now focus on this feature.

[Matheus-Garbelini]

@bblanchon, @mahmed8003, @cosmikwolf there's a new PR of mine that includes an initial support to messagepack: #682, if anyone could test more with an arduino I'd be glad. Thanks.

[bblanchon]

MessagePack is finally available in ArduinoJson 6.0.0