incremental parsing with sax_parser

[AlexandreBossard]

I'm reading (possibly big) json data from the network. I'm using boost:asio for that. I would have expected something of the like:

json::json_sax_t* sax_parser_ = new...;
for (auto it, net::buffer_sequence_begin(buffers); it != net::buffer_sequence_end(buffers); ++it)
{
   net::const_buffer buffer = *it;
   nlohmann::json::sax_parse(
       buffer.data(), buffer.data() + buffer().size(), sax_parser_);
}
return sax_parser_.json();

An asio read() returns a Sequence of buffer(an container of char*). So I need to call json::sax_parse multiple times.

I have not found a default sax_parser implementation. One that just build a json incrementatlly with consecutive calls to sax_parse()

Do I have to write my own for such (I believe) a simple task ?

Actually, I exactly want to do this #605 (comment)

[nlohmann]

The parser accepts an iterator range as input - as long as you can wrap your input in a type with a begin() and end() function, that should work. The default parser is here: https://github.com/nlohmann/json/blob/develop/include/nlohmann/detail/input/json_sax.hpp#L145

[AlexandreBossard]

Why is it in a detail namespace ? Is it safe to use regarding api stability ?

[nlohmann]

It is in the detail namespace as this is the parser used by the library by default. You can provide your own input adapter and pass it to the parse function.

[AlexandreBossard]

I was more concern about api stability (will it break ?) and why it's not documented. Re-Implementing a sax parser seems unnecessary if there is a perfectly good one for incremental parsing.

[nlohmann]

You do not need to reimplement it - sorry for the confusion. You only need to define an input adapter.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.