Add ifAlias label to netdev collector (prometheus#3087)

Signed-off-by: Tomas Vilemaitis <tomas.vilemaitis@gmail.com>
Signed-off-by: Vitaly Zhuravlev <v-zhuravlev@users.noreply.github.com>

collector/netdev_common.go

@@ -93,15 +93,15 @@ func NewNetDevCollector(logger log.Logger) (Collector, error) {
 	}, nil
 }
 
-func (c *netDevCollector) metricDesc(key string) *prometheus.Desc {
+func (c *netDevCollector) metricDesc(key string, labels []string) *prometheus.Desc {
 	c.metricDescsMutex.Lock()
 	defer c.metricDescsMutex.Unlock()
 
 	if _, ok := c.metricDescs[key]; !ok {
 		c.metricDescs[key] = prometheus.NewDesc(
 			prometheus.BuildFQName(namespace, c.subsystem, key+"_total"),
 			fmt.Sprintf("Network device statistic %s.", key),
-			[]string{"device"},
+			labels,
 			nil,
 		)
 	}
@@ -114,13 +114,29 @@ func (c *netDevCollector) Update(ch chan<- prometheus.Metric) error {
 	if err != nil {
 		return fmt.Errorf("couldn't get netstats: %w", err)
 	}
+
+	netDevLabels, err := getNetDevLabels()
+	if err != nil {
+		return fmt.Errorf("couldn't get netdev labels: %w", err)
+	}
+
 	for dev, devStats := range netDev {
 		if !*netdevDetailedMetrics {
 			legacy(devStats)
 		}
+
+		labels := []string{"device"}
+		labelValues := []string{dev}
+		if devLabels, exists := netDevLabels[dev]; exists {
+			for labelName, labelValue := range devLabels {
+				labels = append(labels, labelName)
+				labelValues = append(labelValues, labelValue)
+			}
+		}
+
 		for key, value := range devStats {
-			desc := c.metricDesc(key)
-			ch <- prometheus.MustNewConstMetric(desc, prometheus.CounterValue, float64(value), dev)
+			desc := c.metricDesc(key, labels)
+			ch <- prometheus.MustNewConstMetric(desc, prometheus.CounterValue, float64(value), labelValues...)
 		}
 	}
 	if *netdevAddressInfo {

collector/netdev_darwin.go

@@ -118,3 +118,8 @@ type ifData64 struct {
 	Xmittiming uint32
 	Lastchange unix.Timeval32
 }
+
+func getNetDevLabels() (map[string]map[string]string, error) {
+	// to be implemented if needed
+	return nil, nil
+}

collector/netdev_linux.go

@@ -24,10 +24,12 @@ import (
 	"github.com/go-kit/log/level"
 	"github.com/jsimonetti/rtnetlink"
 	"github.com/prometheus/procfs"
+	"github.com/prometheus/procfs/sysfs"
 )
 
 var (
-	netDevNetlink = kingpin.Flag("collector.netdev.netlink", "Use netlink to gather stats instead of /proc/net/dev.").Default("true").Bool()
+	netDevNetlink      = kingpin.Flag("collector.netdev.netlink", "Use netlink to gather stats instead of /proc/net/dev.").Default("true").Bool()
+	netdevLabelIfAlias = kingpin.Flag("collector.netdev.label-ifalias", "Add ifAlias label").Default("false").Bool()
 )
 
 func getNetDevStats(filter *deviceFilter, logger log.Logger) (netDevStats, error) {
@@ -184,3 +186,26 @@ func procNetDevStats(filter *deviceFilter, logger log.Logger) (netDevStats, erro
 
 	return metrics, nil
 }
+
+func getNetDevLabels() (map[string]map[string]string, error) {
+	if !*netdevLabelIfAlias {
+		return nil, nil
+	}
+
+	fs, err := sysfs.NewFS(*sysPath)
+	if err != nil {
+		return nil, err
+	}
+
+	interfaces, err := fs.NetClass()
+	if err != nil {
+		return nil, err
+	}
+
+	labels := make(map[string]map[string]string)
+	for iface, params := range interfaces {
+		labels[iface] = map[string]string{"ifalias": params.IfAlias}
+	}
+
+	return labels, nil
+}

collector/netdev_openbsd.go

@@ -72,3 +72,8 @@ func getNetDevStats(filter *deviceFilter, logger log.Logger) (netDevStats, error
 
 	return netDev, nil
 }
+
+func getNetDevLabels() (map[string]map[string]string, error) {
+	// to be implemented if needed
+	return nil, nil
+}

collector/netdev_openbsd_amd64.go

@@ -20,8 +20,9 @@ import (
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 
-	"golang.org/x/sys/unix"
 	"unsafe"
+
+	"golang.org/x/sys/unix"
 )
 
 func getNetDevStats(filter *deviceFilter, logger log.Logger) (netDevStats, error) {
@@ -76,3 +77,8 @@ func getNetDevStats(filter *deviceFilter, logger log.Logger) (netDevStats, error
 	}
 	return netDev, nil
 }
+
+func getNetDevLabels() (map[string]map[string]string, error) {
+	// to be implemented if needed
+	return nil, nil
+}