DOSGuard.hpp

#pragma once
 
#include "util/Mutex.hpp"
#include "util/config/ConfigDefinition.hpp"
#include "util/log/Logger.hpp"
#include "web/dosguard/DOSGuardInterface.hpp"
#include "web/dosguard/WeightsInterface.hpp"
#include "web/dosguard/WhitelistHandlerInterface.hpp"
 
#include <boost/asio.hpp>
#include <boost/iterator/transform_iterator.hpp>
#include <boost/json/object.hpp>
#include <boost/system/error_code.hpp>
 
#include <cstdint>
#include <functional>
#include <string>
#include <string_view>
#include <unordered_map>
#include <unordered_set>
 
namespace web::dosguard {

class DOSGuard : public DOSGuardInterface {
    struct ClientState {
        std::uint32_t transferredByte = 0; 
        std::uint32_t requestsCount = 0;   
    };
 
    struct State {
        std::unordered_map<std::string, ClientState> ipState;
        std::unordered_map<std::string, std::uint32_t> ipConnCount;
    };
    util::Mutex<State> mtx_;
 
    std::reference_wrapper<WhitelistHandlerInterface const> whitelistHandler_;
    std::reference_wrapper<WeightsInterface const> weights_;
 
    std::uint32_t const maxFetches_;
    std::uint32_t const maxConnCount_;
    std::uint32_t const maxRequestCount_;
    util::Logger log_{"RPC"};
 
public:
    DOSGuard(
        util::config::ClioConfigDefinition const& config,
        WhitelistHandlerInterface const& whitelistHandler,
        WeightsInterface const& weights
    );

    [[nodiscard]] bool
    isWhiteListed(std::string_view const ip) const noexcept override;

    [[nodiscard]] bool
    isOk(std::string const& ip) const noexcept override;

    void
    increment(std::string const& ip) noexcept override;

    void
    decrement(std::string const& ip) noexcept override;

    [[maybe_unused]] bool
    add(std::string const& ip, uint32_t numObjects) noexcept override;

    [[maybe_unused]] bool
    request(std::string const& ip, boost::json::object const& request) override;

    void
    clear() noexcept override;
 
private:
    [[nodiscard]] static std::unordered_set<std::string>
    getWhitelist(util::config::ClioConfigDefinition const& config);
};
 
}  // namespace web::dosguard