ClickHouse/dbms/programs/server/MetricsTransmitter.h

#pragma once

#include <condition_variable>
#include <mutex>
#include <string>
#include <thread>
#include <vector>
#include <Common/ProfileEvents.h>
#include <Common/ThreadPool.h>


namespace DB
{

class AsynchronousMetrics;
class Context;


/**    Automatically sends
  * - difference of ProfileEvents;
  * - values of CurrentMetrics;
  * - values of AsynchronousMetrics;
  *  to Graphite at beginning of every minute.
  */
class MetricsTransmitter
{
public:
    MetricsTransmitter(Context & context_,
                       const AsynchronousMetrics & async_metrics_,
                       const std::string & config_name_)
        : context(context_)
        , async_metrics(async_metrics_)
        , config_name(config_name_)
    {
    }
    ~MetricsTransmitter();

private:
    void run();
    void transmit(std::vector<ProfileEvents::Count> & prev_counters);

    Context & context;

    const AsynchronousMetrics & async_metrics;
    const std::string config_name;

    bool quit = false;
    std::mutex mutex;
    std::condition_variable cond;
    ThreadFromGlobalPool thread{&MetricsTransmitter::run, this};

    static constexpr auto profile_events_path_prefix = "ClickHouse.ProfileEvents.";
    static constexpr auto current_metrics_path_prefix = "ClickHouse.Metrics.";
    static constexpr auto asynchronous_metrics_path_prefix = "ClickHouse.AsynchronousMetrics.";
};

}