request_body.hpp

// SPDX-FileCopyrightText: 2026 Klaus Reimer <k@ailis.de>
// SPDX-License-Identifier: MIT
 
#pragma once
 
#include <kaycxx/http/sized_istream.hpp>
 
#include <nlohmann/json.hpp>
 
#include <cstddef>
#include <cstdint>
#include <functional>
#include <iosfwd>
#include <optional>
#include <span>
#include <string>
#include <string_view>
#include <variant>
#include <vector>
 
namespace kaycxx::http {
 
class client;
class multipart_form;
class url_encoded_form;

class request_body {
public:
    request_body() noexcept;

    request_body(std::string_view body) noexcept;

    request_body(const std::string& body) noexcept;

    request_body(const char* body);

    request_body(std::span<const std::byte> body) noexcept;

    request_body(std::span<std::byte> body) noexcept;

    request_body(const std::vector<std::byte>& body) noexcept;

    request_body(std::istream& input) noexcept;

    request_body(sized_istream input) noexcept;

    request_body(const nlohmann::json& body) noexcept;

    request_body(const url_encoded_form& body) noexcept;

    request_body(const multipart_form& body) noexcept;
 
private:
    struct stream_data {
        std::reference_wrapper<std::istream> input;

        std::optional<std::uint64_t> size;
    };

    using value_type = std::variant<
        std::monostate,
        std::string_view,
        std::span<const std::byte>,
        stream_data,
        std::reference_wrapper<const nlohmann::json>,
        std::reference_wrapper<const url_encoded_form>,
        std::reference_wrapper<const multipart_form>
    >;

    value_type value_{};
 
    friend class client;
};
 
} // namespace kaycxx::http