json.h

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#pragma once
#include "json.hpp"  // nlohmann::json
 
namespace ga {
using Json = nlohmann::json;
 
namespace json {
    // json parser utility functions
 
    template <typename T>
    inline T getValue( const ga::Json& json, const std::string& keyOrPointer, const T& defaultValue )
    {
        T ret = defaultValue;
        try {
            if ( keyOrPointer.empty() || keyOrPointer.at( 0 ) == '/' ) {
                // allow for json pointer paths - these are either empty or begin with '/'
                ret = json.at(ga::Json::json_pointer( keyOrPointer )).get<T>();
            } else {
                // assume key is a normal key for a json object
                ret = json.at(keyOrPointer).get<T>();
            }
        } catch ( ... ) {
            // todo: log warning? accept an ostream& for logging?
        }
        return ret;
    }
 
    inline std::string getValue( const ga::Json& json, const std::string& keyOrPointer, const char* defaultValue )
    {
        return getValue( json, keyOrPointer, std::string( defaultValue ) );
    }
 
}  // namespace json
}  // namespace ga