folly::Optional BasicQuantileStatMap::getValue()

in fb303/detail/QuantileStatMap-inl.h [38:77]

• 36 lines of code
• 7 McCabe index (conditional complexity)

folly::Optional<int64_t> BasicQuantileStatMap<ClockT>::getValue(
    folly::StringPiece key) const {
  CounterMapEntry cme;
  {
    folly::SharedMutex::ReadHolder g(mutex_);
    auto it = counterMap_.find(key);
    if (it == counterMap_.end()) {
      return folly::none;
    }
    cme = it->second;
  }
  folly::Range<const double*> r;
  if (cme.statDef.type == ExportType::PERCENT) {
    r = folly::Range<const double*>(&cme.statDef.quantile, 1);
  }

  auto estimates = cme.stat->getEstimates(r);

  const folly::QuantileEstimates* qe = nullptr;
  if (cme.slidingWindowLength) {
    for (const auto& slidingWindow : estimates.slidingWindows) {
      auto slidingWindowLength = slidingWindow.slidingWindowLength();
      if (slidingWindowLength == cme.slidingWindowLength) {
        qe = &slidingWindow.estimate;
        break;
      }
    }
  } else {
    qe = &estimates.allTimeEstimate;
  }

  if (!qe) {
    return folly::none;
  }

  return extractValue(
      cme.statDef,
      *qe,
      statDuration<ClockT>(cme.slidingWindowLength, cme.stat->creationTime()));
}