export application metrics via /metrics

collector/prometheus_collector.go

@@ -184,6 +184,14 @@ func (s byName) Less(i, j int) bool {
 	return s.prometheusLabels[i].GetName() < s.prometheusLabels[j].GetName()
 }
 
+func prometheusLabelSetToCadvisorLabels(promLabels model.Metric) map[string]string {
+	labels := make(map[string]string)
+	for k, v := range promLabels {
+		labels[string(k)] = string(v)
+	}
+	return labels
+}
+
 func prometheusLabelSetToCadvisorLabel(promLabels model.Metric) string {
 	labels := labelSetToLabelPairs(promLabels)
 	sort.Sort(byName{labels})
@@ -247,11 +255,13 @@ func (collector *PrometheusCollector) Collect(metrics map[string][]v1.MetricVal)
 			// TODO Handle multiple labels nicer. Prometheus metrics can have multiple
 			// labels, cadvisor only accepts a single string for the metric label.
 			label := prometheusLabelSetToCadvisorLabel(sample.Metric)
+			labels := prometheusLabelSetToCadvisorLabels(sample.Metric)
 
 			metric := v1.MetricVal{
 				FloatValue: float64(sample.Value),
 				Timestamp:  sample.Timestamp.Time(),
 				Label:      label,
+				Labels:     labels,
 			}
 			newMetrics[metName] = append(newMetrics[metName], metric)
 			if len(newMetrics) > collector.metricCountLimit {

info/v1/metric.go

@@ -68,7 +68,8 @@ type MetricValBasic struct {
 // An exported metric.
 type MetricVal struct {
 	// Label associated with a metric
-	Label string `json:"label,omitempty"`
+	Label  string            `json:"label,omitempty"`
+	Labels map[string]string `json:"labels,omitempty"`
 
 	// Time at which the metric was queried
 	Timestamp time.Time `json:"timestamp"`

metrics/prometheus.go

@@ -17,6 +17,7 @@ package metrics
 import (
 	"fmt"
 	"regexp"
+	"strings"
 	"time"
 
 	"github.com/google/cadvisor/container"
@@ -1675,6 +1676,36 @@ func (c *PrometheusCollector) collectContainersInfo(ch chan<- prometheus.Metric)
 			}
 		}
 	}
+
+	if c.includedMetrics.Has(container.AppMetrics) {
+		for _, container := range containers {
+			cstats := container.Stats
+			if len(cstats) > 0 {
+				last := cstats[len(cstats)-1]
+				for metricLabel, v := range last.CustomMetrics {
+					for _, metric := range v {
+						values := make([]string, 0, len(metric.Labels)+2)
+						labels := make([]string, 0, len(metric.Labels)+2)
+						labels = append(labels, "container_name")
+						values = append(values, container.ContainerReference.Name)
+						alias := strings.Join(container.ContainerReference.Aliases, ".")
+						labels = append(labels, "container_alias")
+						values = append(values, alias)
+						for label, value := range metric.Labels {
+							if label == "__name__" {
+								continue
+							}
+							labels = append(labels, sanitizeLabelName(label))
+							values = append(values, value)
+						}
+						desc := prometheus.NewDesc(metricLabel, "Custom application metric.", labels, nil)
+						ch <- prometheus.MustNewConstMetric(desc, prometheus.GaugeValue, float64(metric.FloatValue), values...)
+					}
+				}
+
+			}
+		}
+	}
 }
 
 func (c *PrometheusCollector) collectVersionInfo(ch chan<- prometheus.Metric) {