func()

in v1storage/storage.go [515:546]

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

func (s *MemorySeriesStorage) LastSampleForLabelMatchers(_ context.Context, cutoff model.Time, matcherSets ...metric.LabelMatchers) (model.Vector, error) {
	mergedFPs := map[model.Fingerprint]struct{}{}
	for _, matchers := range matcherSets {
		fps, err := s.fpsForLabelMatchers(cutoff, model.Latest, matchers...)
		if err != nil {
			return nil, err
		}
		for fp := range fps {
			mergedFPs[fp] = struct{}{}
		}
	}

	res := make(model.Vector, 0, len(mergedFPs))
	for fp := range mergedFPs {
		s.fpLocker.Lock(fp)

		series, ok := s.fpToSeries.get(fp)
		if !ok {
			// A series could have disappeared between resolving label matchers and here.
			s.fpLocker.Unlock(fp)
			continue
		}
		sp := series.lastSamplePair()
		res = append(res, &model.Sample{
			Metric:    series.metric,
			Value:     sp.Value,
			Timestamp: sp.Timestamp,
		})
		s.fpLocker.Unlock(fp)
	}
	return res, nil
}