hybrid_log_exporter.hpp

/* -*- mode: c++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * Copyright (C) 2025 Marco Craveiro <marco.craveiro@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; either version 3 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */
#ifndef ORES_TELEMETRY_EXPORTING_HYBRID_LOG_EXPORTER_HPP
#define ORES_TELEMETRY_EXPORTING_HYBRID_LOG_EXPORTER_HPP
 
#include <atomic>
#include <chrono>
#include <condition_variable>
#include <cstdint>
#include <filesystem>
#include <fstream>
#include <functional>
#include <memory>
#include <mutex>
#include <thread>
#include <vector>
#include "ores.telemetry/exporting/log_exporter.hpp"
#include "ores.telemetry/exporting/telemetry_options.hpp"
#include "ores.telemetry/exporting/upload_position_tracker.hpp"
 
namespace ores::telemetry::exporting {
 
using send_records_callback =
    std::function<bool(std::vector<domain::log_record>)>;
 
class hybrid_log_exporter final : public log_exporter {
public:
    hybrid_log_exporter(const std::filesystem::path& file_path,
                        telemetry_options options,
                        send_records_callback send_callback = nullptr);
 
    ~hybrid_log_exporter() override;
 
    hybrid_log_exporter(const hybrid_log_exporter&) = delete;
    hybrid_log_exporter& operator=(const hybrid_log_exporter&) = delete;
 
    void export_record(domain::log_record record) override;
 
    void flush() override;
 
    void shutdown() override;
 
    void set_connected(bool connected);
 
    std::uint64_t upload_position() const;
 
private:
    void write_to_file(const domain::log_record& record);
 
    void add_to_batch(domain::log_record record);
 
    bool send_batch();
 
    void flush_thread_func();
 
    // File export
    std::mutex file_mutex_;
    std::ofstream file_;
    std::filesystem::path file_path_;
    std::uint64_t file_position_ = 0;
 
    // Options
    telemetry_options options_;
    send_records_callback send_callback_;
 
    // Streaming state
    std::mutex batch_mutex_;
    std::vector<domain::log_record> pending_batch_;
    upload_position_tracker position_tracker_;
    std::atomic<bool> connected_{false};
 
    // Background flush thread
    std::thread flush_thread_;
    std::condition_variable flush_cv_;
    std::atomic<bool> shutdown_requested_{false};
    std::chrono::steady_clock::time_point last_flush_time_;
};
 
}
 
#endif