jsonata-cpp

C++ implementation of JSONata.

This is a C++ port of the JSONata reference implementation, and also borrows from the Dashjoin Java port.

This implementation supports 100% of the language features of JSONata, using nlohmann_json. The JSONata documentation can be found here.

Installation

Installation uses CMake as follows:

include(FetchContent)

FetchContent_Declare(
    jsonata
    URL https://github.com/rayokota/jsonata-cpp/archive/refs/tags/v0.1.0.zip
    URL_HASH SHA256=3ee1798f28a29d36ebbb273853979926716a384e4d491a6bd408e1f6de51760d  # Optional
)
FetchContent_MakeAvailable(jsonata)

# Use the library
target_link_libraries(your_target jsonata::jsonata)

Getting Started

A very simple start:

#include <iostream>
#include <jsonata/Jsonata.h>
#include <nlohmann/json.hpp>

int main() {
    // Create the JSON data
    auto data = nlohmann::ordered_json::parse(R"({
        "example": [
            {"value": 4}, 
            {"value": 7}, 
            {"value": 13}
        ]
    })");

    // Create the JSONata expression
    jsonata::Jsonata expr("$sum(example.value)");
    
    // Evaluate the expression with the data
    auto result = expr.evaluate(data);
    
    // Print the result
    std::cout << "Result: " << result << std::endl;
    
    return 0;
}

Running Tests

This project uses the repository of the reference implementation as a submodule. This allows referencing the current version of the unit tests. To clone this repository, run:

git clone --recurse-submodules https://github.com/rayokota/jsonata-cpp

To build and run the unit tests:

cmake -DJSONATA_BUILD_TESTS=ON -S . -B build
cmake --build build
ctest --test-dir build