Merge pull request #66 from bakins/extended-config

Allow histograms for timer metrics
prometheus · Aug 3, 2017 · aeab290 · aeab290
2 parents a31feb5 + 9bca336
commit aeab290
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Showing 22 changed files with 9,955 additions and 91 deletions.
diff --git a/README.md b/README.md
@@ -132,6 +132,76 @@ follows:
     test.web-server.foo.bar
      => test_web__server_foo_bar{}
 
+
+YAML may also be used for the configuration if the passed filename ends in `.yml` or
+`.yaml`.  The above example mapping, in YAML, would be:
+
+```yaml
+mappings:
+- match: test.dispatcher.*.*.*
+  labels:
+    name: "dispatcher_events_total"
+    processor: "$1"
+    action: "$2"
+    outcome: "$3"
+    job: "test_dispatcher"
+- match: *.signup.*.*
+  labels:
+    name: "signup_events_total"
+    provider: "$2"
+    outcome: "$3"
+    job: "${1}_server"
+```
+
+Using the YAML configuration, one may also set the timer type to "histogram". The 
+default is "summary" as in the plain text configuration format.  For example,
+to set the timer type for a single metric:
+
+```yaml
+mappings:
+- match: test.timing.*.*.*
+  timer_type: histogram
+  buckets: [ 0.01, 0.025, 0.05, 0.1 ]
+  labels: 
+    name: "my_timer"
+    provider: "$2"
+    outcome: "$3"
+    job: "${1}_server"
+```
+
+Note, that one may also set the histogram buckets.  If not set, then the default
+[Prometheus client values](https://godoc.org/github.com/prometheus/client_golang/prometheus#pkg-variables) are used: `[.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10]`. `+Inf` is added
+automatically.
+
+`timer_type` is only used when the statsd metric type is a timer. `buckets` is
+only used when the statsd metric type is a timerand the `timer_type` is set to
+"histogram."
+
+One may also set defaults for the timer type and the buckets. These will be used
+by all mappings that do not define these.
+
+```yaml
+defaults:
+  timer_type: histogram
+  buckets: [.005, .01, .025, .05, .1, .25, .5, 1, 2.5 ]
+mappings:
+# This will be a histogram using the buckets set in `defaults`.
+- match: test.timing.*.*.*
+  labels: 
+    name: "my_timer"
+    provider: "$2"
+    outcome: "$3"
+    job: "${1}_server"
+# This will be a summary timer.
+- match: other.timing.*.*.*
+  timer_type: summary
+  labels: 
+    name: "other_timer"
+    provider: "$2"
+    outcome: "$3"
+    job: "${1}_server_other"
+```
+
 ## Using Docker
 
 You can deploy this exporter using the [prom/statsd-exporter](https://registry.hub.docker.com/u/prom/statsd-exporter/) Docker image.

diff --git a/exporter.go b/exporter.go
@@ -143,6 +143,41 @@ func (c *SummaryContainer) Get(metricName string, labels prometheus.Labels) (pro
 	return summary, nil
 }
 
+type HistogramContainer struct {
+	Elements map[uint64]prometheus.Histogram
+	mapper   *metricMapper
+}
+
+func NewHistogramContainer(mapper *metricMapper) *HistogramContainer {
+	return &HistogramContainer{
+		Elements: make(map[uint64]prometheus.Histogram),
+		mapper:   mapper,
+	}
+}
+
+func (c *HistogramContainer) Get(metricName string, labels prometheus.Labels, mapping *metricMapping) (prometheus.Histogram, error) {
+	hash := hashNameAndLabels(metricName, labels)
+	histogram, ok := c.Elements[hash]
+	if !ok {
+		buckets := c.mapper.Defaults.Buckets
+		if mapping != nil && mapping.Buckets != nil && len(mapping.Buckets) > 0 {
+			buckets = mapping.Buckets
+		}
+		histogram = prometheus.NewHistogram(
+			prometheus.HistogramOpts{
+				Name:        metricName,
+				Help:        defaultHelp,
+				ConstLabels: labels,
+				Buckets:     buckets,
+			})
+		c.Elements[hash] = histogram
+		if err := prometheus.Register(histogram); err != nil {
+			return nil, err
+		}
+	}
+	return histogram, nil
+}
+
 type Event interface {
 	MetricName() string
 	Value() float64
@@ -183,11 +218,12 @@ func (c *TimerEvent) Labels() map[string]string { return c.labels }
 type Events []Event
 
 type Exporter struct {
-	Counters  *CounterContainer
-	Gauges    *GaugeContainer
-	Summaries *SummaryContainer
-	mapper    *metricMapper
-	addSuffix bool
+	Counters   *CounterContainer
+	Gauges     *GaugeContainer
+	Summaries  *SummaryContainer
+	Histograms *HistogramContainer
+	mapper     *metricMapper
+	addSuffix  bool
 }
 
 func escapeMetricName(metricName string) string {
@@ -220,7 +256,7 @@ func (b *Exporter) Listen(e <-chan Events) {
 			metricName := ""
 			prometheusLabels := event.Labels()
 
-			labels, present := b.mapper.getMapping(event.MetricName())
+			mapping, labels, present := b.mapper.getMapping(event.MetricName())
 			if present {
 				metricName = labels["name"]
 				for label, value := range labels {
@@ -275,17 +311,44 @@ func (b *Exporter) Listen(e <-chan Events) {
 				}
 
 			case *TimerEvent:
-				summary, err := b.Summaries.Get(
-					b.suffix(metricName, "timer"),
-					prometheusLabels,
-				)
-				if err == nil {
-					summary.Observe(event.Value())
+				t := timerTypeDefault
+				if mapping != nil {
+					t = mapping.TimerType
+				}
+				if t == timerTypeDefault {
+					t = b.mapper.Defaults.TimerType
+				}
 
-					eventStats.WithLabelValues("timer").Inc()
-				} else {
-					log.Errorf(regErrF, metricName, err)
-					conflictingEventStats.WithLabelValues("timer").Inc()
+				switch t {
+				case timerTypeHistogram:
+					histogram, err := b.Histograms.Get(
+						b.suffix(metricName, "timer"),
+						prometheusLabels,
+						mapping,
+					)
+					if err == nil {
+						histogram.Observe(event.Value())
+						eventStats.WithLabelValues("timer").Inc()
+					} else {
+						log.Errorf(regErrF, metricName, err)
+						conflictingEventStats.WithLabelValues("timer").Inc()
+					}
+
+				case timerTypeDefault, timerTypeSummary:
+					summary, err := b.Summaries.Get(
+						b.suffix(metricName, "timer"),
+						prometheusLabels,
+					)
+					if err == nil {
+						summary.Observe(event.Value())
+						eventStats.WithLabelValues("timer").Inc()
+					} else {
+						log.Errorf(regErrF, metricName, err)
+						conflictingEventStats.WithLabelValues("timer").Inc()
+					}
+
+				default:
+					panic(fmt.Sprintf("unknown timer type '%s'", t))
 				}
 
 			default:
@@ -298,11 +361,12 @@ func (b *Exporter) Listen(e <-chan Events) {
 
 func NewExporter(mapper *metricMapper, addSuffix bool) *Exporter {
 	return &Exporter{
-		addSuffix: addSuffix,
-		Counters:  NewCounterContainer(),
-		Gauges:    NewGaugeContainer(),
-		Summaries: NewSummaryContainer(),
-		mapper:    mapper,
+		addSuffix:  addSuffix,
+		Counters:   NewCounterContainer(),
+		Gauges:     NewGaugeContainer(),
+		Summaries:  NewSummaryContainer(),
+		Histograms: NewHistogramContainer(mapper),
+		mapper:     mapper,
 	}
 }