jsonpath (adapt for nlohmann/json)

A C++ jsonpath library using Boost.Spirit V3 and range-v3 for the parser.

The goal of the jsonpath library was to create a conformant jsonpath parser that could be used for nlohmann/json.

follow the majority rules in http://goessner.net/articles/JsonPath/ but also with some minor differences.

this library is till bleeding edge, so use it at your own risk.

Quick Example

// header files
#include "json/json.hpp"
#include "jsonpath/jsonpath.hpp"

using nlohmann
using coatan::jsonpath;

jsonpath p("$.school.rank");
if(p.valid()) {
    json j; // sample data
    json r = p.val(j); // result
}

Examples

given these example data

{
    "store": {
        "book": [
            {
                "category": "reference",
                "author": "Nigel Rees",
                "title": "Sayings of the Century",
                "price": 8.95
            },
            {
                "category": "fiction",
                "author": "Evelyn Waugh",
                "title": "Sword of Honour",
                "price": 12.99
            },
            {
                "category": "fiction",
                "author": "Herman Melville",
                "title": "Moby Dick",
                "isbn": "0-553-21311-3",
                "price": 8.99
            },
            {
                "category": "fiction",
                "author": "J. R. R. Tolkien",
                "title": "The Lord of the Rings",
                "isbn": "0-395-19395-8",
                "price": 22.99
            }
        ],
        "bicycle": {
            "color": "red",
            "price": 19.95
        }
    },
    "expensive": 10
}

example json path syntax.

jsonpath	result
$.store.bicycle.color	["red"]
$.store.book[0,-1].price	[8.95, 22.99]
$.store.book[-2:].price	[8.99, 22.99]
$.store.book[0:3:2].price	[8.95, 8.99]
$.store.book[?(@.isbn&&@.title=='Moby Dick')].price	[8.99]
$.store.book[?(@.price<$.expensive)].price	[8.95, 8.99]
$.store.book[?(@.title~=/Sword.*/i)].author	["Evelyn Waugh"]
$..price	[19.95, 8.95, 12.99, 8.99, 22.99]

Building

We have CMake support.

cd jsonspirit
mkdir bin
mkdir build
cd build
cmake ..
make

Licensing