Serialize big data in json

[Roman-Koshelev]

For example, I want to add logged events to a JSON file and close it when I exit the program. I would also like to add them to a file as they become available.

What should I do to I make this work?

[ilqvya]

nop, json currently load ALL json into memory. It's a big feature to store part of json in memory depending on file pointers :)

[nlohmann]

You can use the SAX interface to avoid parsing everything to memory. See https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a8a3dd150c2d1f0df3502d937de0871db.html#a8a3dd150c2d1f0df3502d937de0871db for more information.

[pbialas7]

But can you use SAX to write not parse json to file?

[ilqvya]

@nlohmann can i use it with memory mapped file (if i have just pointer to data and its size) ?

[nlohmann]

But can you use SAX to write not parse json to file?

No this is not possible in the moment.

[nlohmann]

@nlohmann can i use it with memory mapped file (if i have just pointer to data and its size) ?

Yes, you can do this with

json j = json::parse({data, size});

[nlohmann]

Do you need further assistance with this issue?