traits.h

#define JWT_DISABLE_PICOJSON
#define JSONCONS_NO_DEPRECATED
 
#include "jwt-cpp/jwt.h"
 
#include "jsoncons/json.hpp"
 
#include <sstream>
 
namespace jwt {
    namespace traits {
        struct danielaparker_jsoncons {
            // Needs at least https://github.com/danielaparker/jsoncons/commit/28c56b90ec7337f98a5b8942574590111a5e5831
            static_assert(jsoncons::version().minor >= 167, "A higher version of jsoncons is required!");
 
            using json = jsoncons::json;
            using value_type = json;
            struct object_type : json::object {
                // Add missing C++11 member types
                // https://github.com/danielaparker/jsoncons/commit/1b1ceeb572f9a2db6d37cff47ac78a4f14e072e2#commitcomment-45391411
                using value_type = key_value_type; // Enable optional jwt-cpp methods
                using mapped_type = key_value_type::value_type;
                using size_type = size_t; // for implementing count
 
                object_type() = default;
                object_type(const object_type&) = default;
                explicit object_type(const json::object& o) : json::object(o) {}
                object_type(object_type&&) = default;
                explicit object_type(json::object&& o) : json::object(o) {}
                ~object_type() = default;
                object_type& operator=(const object_type& o) = default;
                object_type& operator=(object_type&& o) noexcept = default;
 
                // Add missing C++11 subscription operator
                mapped_type& operator[](const key_type& key) {
                    // https://github.com/microsoft/STL/blob/2914b4301c59dc7ffc09d16ac6f7979fde2b7f2c/stl/inc/map#L325
                    return try_emplace(key).first->value();
                }
 
                // Add missing C++11 element access
                const mapped_type& at(const key_type& key) const {
                    auto target = find(key);
                    if (target != end()) return target->value();
 
                    throw std::out_of_range("invalid key");
                }
 
                // Add missing C++11 lookup method
                size_type count(const key_type& key) const {
                    struct compare {
                        bool operator()(const value_type& val, const key_type& key) const { return val.key() < key; }
                        bool operator()(const key_type& key, const value_type& val) const { return key < val.key(); }
                    };
 
                    // https://en.cppreference.com/w/cpp/algorithm/binary_search#Complexity
                    if (std::binary_search(this->begin(), this->end(), key, compare{})) return 1;
                    return 0;
                }
            };
            using array_type = json::array;
            using string_type = std::string; // current limitation of traits implementation
            using number_type = double;
            using integer_type = int64_t;
            using boolean_type = bool;
 
            static jwt::json::type get_type(const json& val) {
                using jwt::json::type;
 
                if (val.type() == jsoncons::json_type::bool_value) return type::boolean;
                if (val.type() == jsoncons::json_type::int64_value) return type::integer;
                if (val.type() == jsoncons::json_type::uint64_value) return type::integer;
                if (val.type() == jsoncons::json_type::half_value) return type::number;
                if (val.type() == jsoncons::json_type::double_value) return type::number;
                if (val.type() == jsoncons::json_type::string_value) return type::string;
                if (val.type() == jsoncons::json_type::array_value) return type::array;
                if (val.type() == jsoncons::json_type::object_value) return type::object;
 
                throw std::logic_error("invalid type");
            }
 
            static object_type as_object(const json& val) {
                if (val.type() != jsoncons::json_type::object_value) throw std::bad_cast();
                return object_type(val.object_value());
            }
 
            static array_type as_array(const json& val) {
                if (val.type() != jsoncons::json_type::array_value) throw std::bad_cast();
                return val.array_value();
            }
 
            static string_type as_string(const json& val) {
                if (val.type() != jsoncons::json_type::string_value) throw std::bad_cast();
                return val.as_string();
            }
 
            static number_type as_number(const json& val) {
                if (get_type(val) != jwt::json::type::number) throw std::bad_cast();
                return val.as_double();
            }
 
            static integer_type as_integer(const json& val) {
                if (get_type(val) != jwt::json::type::integer) throw std::bad_cast();
                return val.as<integer_type>();
            }
 
            static boolean_type as_boolean(const json& val) {
                if (val.type() != jsoncons::json_type::bool_value) throw std::bad_cast();
                return val.as_bool();
            }
 
            static bool parse(json& val, const std::string& str) {
                val = json::parse(str);
                return true;
            }
 
            static std::string serialize(const json& val) {
                std::ostringstream os;
                os << jsoncons::print(val);
                return os.str();
            }
        };
    } // namespace traits
} // namespace jwt