Support Processor & Aggregator Plugins

closes #1726

internal/models/makemetric.go

@@ -0,0 +1,150 @@
+package models
+
+import (
+	"log"
+	"math"
+	"time"
+
+	"github.com/influxdata/telegraf"
+)
+
+// makemetric is used by both RunningAggregator & RunningInput
+// to make metrics.
+//   nameOverride: override the name of the measurement being made.
+//   namePrefix:   add this prefix to each measurement name.
+//   nameSuffix:   add this suffix to each measurement name.
+//   pluginTags:   these are tags that are specific to this plugin.
+//   daemonTags:   these are daemon-wide global tags, and get applied after pluginTags.
+//   filter:       this is a filter to apply to each metric being made.
+//   applyFilter:  if false, the above filter is not applied to each metric.
+//                 This is used by Aggregators, because aggregators use filters
+//                 on incoming metrics instead of on created metrics.
+func makemetric(
+	measurement string,
+	fields map[string]interface{},
+	tags map[string]string,
+	nameOverride string,
+	namePrefix string,
+	nameSuffix string,
+	pluginTags map[string]string,
+	daemonTags map[string]string,
+	filter Filter,
+	applyFilter bool,
+	debug bool,
+	mType telegraf.ValueType,
+	t time.Time,
+) telegraf.Metric {
+	if len(fields) == 0 || len(measurement) == 0 {
+		return nil
+	}
+	if tags == nil {
+		tags = make(map[string]string)
+	}
+
+	// Override measurement name if set
+	if len(nameOverride) != 0 {
+		measurement = nameOverride
+	}
+	// Apply measurement prefix and suffix if set
+	if len(namePrefix) != 0 {
+		measurement = namePrefix + measurement
+	}
+	if len(nameSuffix) != 0 {
+		measurement = measurement + nameSuffix
+	}
+
+	// Apply plugin-wide tags if set
+	for k, v := range pluginTags {
+		if _, ok := tags[k]; !ok {
+			tags[k] = v
+		}
+	}
+	// Apply daemon-wide tags if set
+	for k, v := range daemonTags {
+		if _, ok := tags[k]; !ok {
+			tags[k] = v
+		}
+	}
+
+	// Apply the metric filter(s)
+	// for aggregators, the filter does not get applied when the metric is made.
+	// instead, the filter is applied to metric incoming into the plugin.
+	//   ie, it gets applied in the RunningAggregator.Apply function.
+	if applyFilter {
+		if ok := filter.Apply(measurement, fields, tags); !ok {
+			return nil
+		}
+	}
+
+	for k, v := range fields {
+		// Validate uint64 and float64 fields
+		// convert all int & uint types to int64
+		switch val := v.(type) {
+		case uint:
+			fields[k] = int64(val)
+			continue
+		case uint8:
+			fields[k] = int64(val)
+			continue
+		case uint16:
+			fields[k] = int64(val)
+			continue
+		case uint32:
+			fields[k] = int64(val)
+			continue
+		case int:
+			fields[k] = int64(val)
+			continue
+		case int8:
+			fields[k] = int64(val)
+			continue
+		case int16:
+			fields[k] = int64(val)
+			continue
+		case int32:
+			fields[k] = int64(val)
+			continue
+		case uint64:
+			// InfluxDB does not support writing uint64
+			if val < uint64(9223372036854775808) {
+				fields[k] = int64(val)
+			} else {
+				fields[k] = int64(9223372036854775807)
+			}
+			continue
+		case float32:
+			fields[k] = float64(val)
+			continue
+		case float64:
+			// NaNs are invalid values in influxdb, skip measurement
+			if math.IsNaN(val) || math.IsInf(val, 0) {
+				if debug {
+					log.Printf("Measurement [%s] field [%s] has a NaN or Inf "+
+						"field, skipping",
+						measurement, k)
+				}
+				delete(fields, k)
+				continue
+			}
+		}
+
+		fields[k] = v
+	}
+
+	var m telegraf.Metric
+	var err error
+	switch mType {
+	case telegraf.Counter:
+		m, err = telegraf.NewCounterMetric(measurement, tags, fields, t)
+	case telegraf.Gauge:
+		m, err = telegraf.NewGaugeMetric(measurement, tags, fields, t)
+	default:
+		m, err = telegraf.NewMetric(measurement, tags, fields, t)
+	}
+	if err != nil {
+		log.Printf("Error adding point [%s]: %s\n", measurement, err.Error())
+		return nil
+	}
+
+	return m
+}