QueryWatch.h

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/* 
 * Copyright (c) 2021, Daniel Beßler
 * All rights reserved.
 * 
 * This file is part of KnowRob, please consult
 * https://github.com/knowrob/knowrob for license details.
 */
 
#ifndef KNOWROB_MONGO_QUERY_WATCH_H
#define KNOWROB_MONGO_QUERY_WATCH_H
 
#include <mongoc.h>
#include <string>
#include <mutex>
#include <thread>
#include <chrono>
#include <atomic>
#include <map>
#include <knowrob/storage/mongo/ChangeStream.h>
 
namespace knowrob::mongo {
    class QueryWatch {
    public:
        QueryWatch();
 
        QueryWatch(const QueryWatch&) = delete;
 
        ~QueryWatch();
 
        void setWatchRate(uint32_t rate) { watchRate_ = rate; }
 
        long watch(const std::shared_ptr<Collection> &collection,
                   const bson_t *query,
                   const ChangeStreamCallback &callback);
 
        void unwatch(long watcher_id);
 
    protected:
        std::map<long, std::unique_ptr<ChangeStream>> watcher_map_;
 
        std::thread *thread_;
        bool isRunning_;
        std::mutex lock_;
        uint32_t watchRate_;
        static std::atomic<long> id_counter_;
 
        void startWatchThread();
        void stopWatchThread();
        void loop();
    };
}
 
#endif //KNOWROB_MONGO_QUERY_WATCH_H