Add wlan station and interface metrics collection. (#14)

* Fix newlines.
* Added wlan metrics.
* Fix WlanSTA collector - return on errors.

collector/wlanif_collector.go

@@ -0,0 +1,109 @@
+package collector
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+
+	"github.com/prometheus/client_golang/prometheus"
+	log "github.com/sirupsen/logrus"
+	"gopkg.in/routeros.v2/proto"
+)
+
+type wlanIFCollector struct {
+	props        []string
+	descriptions map[string]*prometheus.Desc
+}
+
+func newWlanIFCollector() routerOSCollector {
+	c := &wlanIFCollector{}
+	c.init()
+	return c
+}
+
+func (c *wlanIFCollector) init() {
+	c.props = []string{"channel", "registered-clients", "noise-floor", "overall-tx-ccq"}
+	labelNames := []string{"name", "address", "interface", "channel"}
+	c.descriptions = make(map[string]*prometheus.Desc)
+	for _, p := range c.props {
+		c.descriptions[p] = descriptionForPropertyName("wlan_interface", p, labelNames)
+	}
+}
+
+func (c *wlanIFCollector) describe(ch chan<- *prometheus.Desc) {
+	for _, d := range c.descriptions {
+		ch <- d
+	}
+}
+
+func (c *wlanIFCollector) collect(ctx *collectorContext) error {
+	names, err := c.fetchInterfaceNames(ctx)
+	if err != nil {
+		return err
+	}
+
+	for _, n := range names {
+		err := c.collectForInterface(n, ctx)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (c *wlanIFCollector) fetchInterfaceNames(ctx *collectorContext) ([]string, error) {
+	reply, err := ctx.client.Run("/interface/wireless/print", "?disabled=false", "=.proplist=name")
+	if err != nil {
+		log.WithFields(log.Fields{
+			"device": ctx.device.Name,
+			"error":  err,
+		}).Error("error fetching wireless interface names")
+		return nil, err
+	}
+
+	names := []string{}
+	for _, re := range reply.Re {
+		names = append(names, re.Map["name"])
+	}
+
+	return names, nil
+}
+
+func (c *wlanIFCollector) collectForInterface(iface string, ctx *collectorContext) error {
+	reply, err := ctx.client.Run("/interface/wireless/monitor", fmt.Sprintf("=numbers=%s", iface), "=once=", "=.proplist="+strings.Join(c.props, ","))
+	if err != nil {
+		log.WithFields(log.Fields{
+			"interface": iface,
+			"device":    ctx.device.Name,
+			"error":     err,
+		}).Error("error fetching interface statistics")
+		return err
+	}
+
+	for _, p := range c.props[1:] {
+		// there's always going to be only one sentence in reply, as we
+		// have to explicitly specify the interface
+		c.collectMetricForProperty(p, iface, reply.Re[0], ctx)
+	}
+
+	return nil
+}
+
+func (c *wlanIFCollector) collectMetricForProperty(property, iface string, re *proto.Sentence, ctx *collectorContext) {
+	desc := c.descriptions[property]
+	channel := re.Map["channel"]
+
+	v, err := strconv.ParseFloat(re.Map[property], 64)
+	if err != nil {
+		log.WithFields(log.Fields{
+			"property":  property,
+			"interface": iface,
+			"device":    ctx.device.Name,
+			"error":     err,
+		}).Error("error parsing interface metric value")
+		return
+	}
+
+	ctx.ch <- prometheus.MustNewConstMetric(desc, prometheus.GaugeValue, v, ctx.device.Name, ctx.device.Address, iface, channel)
+}