I want to capture an application traffic and save that to a file so I can then load it on another programs.

I need a library that can do partial serialization (don't know the technical name). I mean, I don't want to hold packets on memory until the program closes, I want to write them to disk when they arrive and free memory. Also I want to be able do lazy deserialization latter. I would prefer any with wide language support (or at least Python and c++).

This is at application layer so packets doesn't contain any network data, they are just byte arrays with additional information like timestamps.

I was looking for known libraries and found Google Protobuf but I don't think it's intended for what I want to do. I tried it, but it mantains the data in memory and seems like I have to serialize the entire object at the end. So the program memory usage keeps growing.

Which C++ library is the best for this case?

EDIT: I need to serialize/deserialize something like this (but not necessarily in json, binary data it's ok for me):

     "date": "2018-08-10T17:03:15Z",
     "version": "",
       "buffer": "xxxxxxxx",
       "date": "2018-08-10T17:18:16Z"
       "buffer": "xxxxxxxx",
       "date": "2018-08-10T17:18:16Z"

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up vote 0 down vote accepted

You can use NDJSON/LDJSON/JSONL format - basically JSON values (without formatting) separated by newlines. You don't need any specific library for this, just basic JSON reader (supplying single lines to it) / writer (appending lines to file).

  • I was looking for a standard so this is what I needed. I also took a look on YAML but seems to be too complex and while it looks powerful, there isn't that much support. Thank you. – Gonzalo Fernandez Oct 14 at 22:30

It seems that you need a kind of json library written in C++. Then, you may take a look at the following link for different json libraries.


Also, I recommend you use the one available at https://github.com/nlohmann/json

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