summary.h

#pragma once
 
#include <chrono>
#include <cstdint>
#include <mutex>
#include <vector>
 
#include "prometheus/client_metric.h"
#include "prometheus/detail/builder.h"  // IWYU pragma: export
#include "prometheus/detail/ckms_quantiles.h"
#include "prometheus/detail/core_export.h"
#include "prometheus/detail/time_window_quantiles.h"
#include "prometheus/metric_type.h"
 
namespace prometheus {

class PROMETHEUS_CPP_CORE_EXPORT Summary {
 public:
  using Quantiles = std::vector<detail::CKMSQuantiles::Quantile>;
 
  static const MetricType metric_type{MetricType::Summary};

  Summary(const Quantiles& quantiles,
          std::chrono::milliseconds max_age = std::chrono::seconds{60},
          int age_buckets = 5);

  void Observe(double value);

  ClientMetric Collect() const;
 
 private:
  const Quantiles quantiles_;
  mutable std::mutex mutex_;
  std::uint64_t count_;
  double sum_;
  detail::TimeWindowQuantiles quantile_values_;
};

PROMETHEUS_CPP_CORE_EXPORT detail::Builder<Summary> BuildSummary();
 
}  // namespace prometheus