std::shared_ptr ServiceData::getQuantileStat()

in fb303/ServiceData.cpp [201:241]

• 38 lines of code
• 6 McCabe index (conditional complexity)

std::shared_ptr<QuantileStat> ServiceData::getQuantileStat(
    folly::StringPiece name,
    folly::Range<const ExportType*> stats,
    folly::Range<const double*> quantiles,
    folly::Range<const size_t*> slidingWindowPeriods) {
  auto stat = quantileMap_.get(name);
  if (stat) {
    return stat;
  }

  std::vector<QuantileStat::SlidingWindow> slidingWindowDefs;
  slidingWindowDefs.reserve(slidingWindowPeriods.size());
  for (const auto& slidingWindowLength : slidingWindowPeriods) {
    if (slidingWindowLength >= 60) {
      auto duration = std::chrono::seconds{slidingWindowLength};
      CHECK_EQ(0, duration.count() % 60);
      slidingWindowDefs.emplace_back(duration / 60, 60);
    } else {
      slidingWindowDefs.emplace_back(
          std::chrono::seconds(1), slidingWindowLength);
    }
  }
  stat = std::make_shared<QuantileStat>(std::move(slidingWindowDefs));

  std::vector<detail::QuantileStatMap::StatDef> statDefs;
  statDefs.reserve(stats.size() + quantiles.size());
  for (auto statType : stats) {
    detail::QuantileStatMap::StatDef statDef;
    statDef.type = statType;
    statDefs.push_back(statDef);
  }
  for (auto quantile : quantiles) {
    detail::QuantileStatMap::StatDef statDef;
    statDef.type = ExportType::PERCENT;
    statDef.quantile = quantile;
    statDefs.push_back(statDef);
  }

  return quantileMap_.registerQuantileStat(
      name, std::move(stat), std::move(statDefs));
}