func()

in plugins/serializers/prometheus/collection.go [183:339]
137 lines of code
29 McCabe index (conditional complexity)

func (c *Collection) Add(metric telegraf.Metric, now time.Time) {
	labels := c.createLabels(metric)
	for _, field := range metric.FieldList() {
		metricName := MetricName(metric.Name(), field.Key, metric.Type())
		metricName, ok := SanitizeMetricName(metricName)
		if !ok {
			continue
		}

		family := MetricFamily{
			Name: metricName,
			Type: metric.Type(),
		}

		entry, ok := c.Entries[family]
		if !ok {
			entry = Entry{
				Family:  family,
				Metrics: make(map[MetricKey]*Metric),
			}
			c.Entries[family] = entry
		}

		metricKey := MakeMetricKey(labels)

		m, ok := entry.Metrics[metricKey]
		if ok {
			// A batch of metrics can contain multiple values for a single
			// Prometheus sample.  If this metric is older than the existing
			// sample then we can skip over it.
			if metric.Time().Before(m.Time) {
				continue
			}
		}

		switch metric.Type() {
		case telegraf.Counter:
			fallthrough
		case telegraf.Gauge:
			fallthrough
		case telegraf.Untyped:
			value, ok := SampleValue(field.Value)
			if !ok {
				continue
			}

			m = &Metric{
				Labels:  labels,
				Time:    metric.Time(),
				AddTime: now,
				Scaler:  &Scaler{Value: value},
			}

			entry.Metrics[metricKey] = m
		case telegraf.Histogram:
			if m == nil {
				m = &Metric{
					Labels:    labels,
					Time:      metric.Time(),
					AddTime:   now,
					Histogram: &Histogram{},
				}
			} else {
				m.Time = metric.Time()
				m.AddTime = now
			}
			switch {
			case strings.HasSuffix(field.Key, "_bucket"):
				le, ok := metric.GetTag("le")
				if !ok {
					continue
				}
				bound, err := strconv.ParseFloat(le, 64)
				if err != nil {
					continue
				}

				count, ok := SampleCount(field.Value)
				if !ok {
					continue
				}

				m.Histogram.merge(Bucket{
					Bound: bound,
					Count: count,
				})
			case strings.HasSuffix(field.Key, "_sum"):
				sum, ok := SampleSum(field.Value)
				if !ok {
					continue
				}

				m.Histogram.Sum = sum
			case strings.HasSuffix(field.Key, "_count"):
				count, ok := SampleCount(field.Value)
				if !ok {
					continue
				}

				m.Histogram.Count = count
			default:
				continue
			}

			entry.Metrics[metricKey] = m
		case telegraf.Summary:
			if m == nil {
				m = &Metric{
					Labels:  labels,
					Time:    metric.Time(),
					AddTime: now,
					Summary: &Summary{},
				}
			} else {
				m.Time = metric.Time()
				m.AddTime = now
			}
			switch {
			case strings.HasSuffix(field.Key, "_sum"):
				sum, ok := SampleSum(field.Value)
				if !ok {
					continue
				}

				m.Summary.Sum = sum
			case strings.HasSuffix(field.Key, "_count"):
				count, ok := SampleCount(field.Value)
				if !ok {
					continue
				}

				m.Summary.Count = count
			default:
				quantileTag, ok := metric.GetTag("quantile")
				if !ok {
					continue
				}
				quantile, err := strconv.ParseFloat(quantileTag, 64)
				if err != nil {
					continue
				}

				value, ok := SampleValue(field.Value)
				if !ok {
					continue
				}

				m.Summary.merge(Quantile{
					Quantile: quantile,
					Value:    value,
				})
			}

			entry.Metrics[metricKey] = m
		}
	}
}