shave a few more nanoseconds

promunifi/clients.go

@@ -82,11 +82,10 @@ func descClient(ns string) *uclient {
 	}
 }
 
-func (u *unifiCollector) exportClients(clients []*unifi.Client) (e []*metricExports) {
+func (u *unifiCollector) exportClients(clients []*unifi.Client, ch chan []*metricExports) {
 	for _, c := range clients {
-		e = append(e, u.exportClient(c)...)
+		ch <- u.exportClient(c)
 	}
-	return
 }
 
 // CollectClient exports Clients' Data

promunifi/collector.go

@@ -54,7 +54,7 @@ type Report struct {
 	Elapsed time.Duration
 	Start   time.Time
 	ch      chan []*metricExports
-	wait    sync.WaitGroup
+	wg      sync.WaitGroup
 }
 
 // NewUnifiCollector returns a prometheus collector that will export any available
@@ -104,7 +104,7 @@ func (u *unifiCollector) Collect(ch chan<- prometheus.Metric) {
 	var err error
 	r := &Report{Start: time.Now(), ch: make(chan []*metricExports)}
 	defer func() {
-		r.wait.Wait()
+		r.wg.Wait()
 		close(r.ch)
 	}()
 
@@ -116,22 +116,23 @@ func (u *unifiCollector) Collect(ch chan<- prometheus.Metric) {
 
 	go u.exportMetrics(ch, r)
 
-	r.wait.Add(2)
-	go func() { r.ch <- u.exportClients(r.Metrics.Clients) }()
-	go func() { r.ch <- u.exportSites(r.Metrics.Sites) }()
+	r.wg.Add(len(r.Metrics.Clients) + len(r.Metrics.Sites))
+	go u.exportClients(r.Metrics.Clients, r.ch)
+	go u.exportSites(r.Metrics.Sites, r.ch)
 
 	if r.Metrics.Devices == nil {
 		return
 	}
 
-	r.wait.Add(4)
-	go func() { r.ch <- u.exportUAPs(r.Metrics.Devices.UAPs) }()
-	go func() { r.ch <- u.exportUSGs(r.Metrics.Devices.USGs) }()
-	go func() { r.ch <- u.exportUSWs(r.Metrics.Devices.USWs) }()
-	go func() { r.ch <- u.exportUDMs(r.Metrics.Devices.UDMs) }()
+	r.wg.Add(len(r.Metrics.Devices.UAPs) + len(r.Metrics.Devices.USGs) + len(r.Metrics.Devices.USWs) + len(r.Metrics.Devices.UDMs))
+	go u.exportUAPs(r.Metrics.Devices.UAPs, r.ch)
+	go u.exportUSGs(r.Metrics.Devices.USGs, r.ch)
+	go u.exportUSWs(r.Metrics.Devices.USWs, r.ch)
+	go u.exportUDMs(r.Metrics.Devices.UDMs, r.ch)
 }
 
-// Call this once (at least as-is). It sets all the counters and runs the logging function.
+// This is closely tied to the method above with a sync.WaitGroup.
+// This method runs in a go routine and exits when the channel closes.
 func (u *unifiCollector) exportMetrics(ch chan<- prometheus.Metric, r *Report) {
 	descs := make(map[*prometheus.Desc]bool) // used as a counter
 	for newMetrics := range r.ch {
@@ -154,7 +155,7 @@ func (u *unifiCollector) exportMetrics(ch chan<- prometheus.Metric, r *Report) {
 				}
 			}
 		}
-		r.wait.Done()
+		r.wg.Done()
 	}
 
 	if u.Config.LoggingFn == nil {

promunifi/site.go

@@ -67,9 +67,9 @@ func descSite(ns string) *site {
 	}
 }
 
-func (u *unifiCollector) exportSites(sites unifi.Sites) (e []*metricExports) {
+func (u *unifiCollector) exportSites(sites unifi.Sites, ch chan []*metricExports) (e []*metricExports) {
 	for _, s := range sites {
-		e = append(e, u.exportSite(s)...)
+		ch <- u.exportSite(s)
 	}
 	return
 }

promunifi/uap.go

@@ -102,11 +102,10 @@ func descUAP(ns string) *uap {
 	}
 }
 
-func (u *unifiCollector) exportUAPs(uaps []*unifi.UAP) (e []*metricExports) {
+func (u *unifiCollector) exportUAPs(uaps []*unifi.UAP, ch chan []*metricExports) {
 	for _, a := range uaps {
-		e = append(e, u.exportUAP(a)...)
+		ch <- u.exportUAP(a)
 	}
-	return
 }
 
 // exportUAP exports Access Point Data

promunifi/udm.go

@@ -11,11 +11,10 @@ func descUDM(ns string) *udm {
 	return &udm{}
 }
 
-func (u *unifiCollector) exportUDMs(udms []*unifi.UDM) (e []*metricExports) {
+func (u *unifiCollector) exportUDMs(udms []*unifi.UDM, ch chan []*metricExports) {
 	for _, d := range udms {
-		e = append(e, u.exportUDM(d)...)
+		ch <- u.exportUDM(d)
 	}
-	return
 }
 
 // exportUDM exports UniFi Dream Machine (and Pro) Data

promunifi/usg.go

@@ -109,11 +109,10 @@ func descUSG(ns string) *usg {
 	}
 }
 
-func (u *unifiCollector) exportUSGs(usgs []*unifi.USG) (e []*metricExports) {
+func (u *unifiCollector) exportUSGs(usgs []*unifi.USG, ch chan []*metricExports) {
 	for _, sg := range usgs {
-		e = append(e, u.exportUSG(sg)...)
+		ch <- u.exportUSG(sg)
 	}
-	return
 }
 
 // exportUSG Exports Security Gateway Data
@@ -122,6 +121,7 @@ func (u *unifiCollector) exportUSG(s *unifi.USG) []*metricExports {
 	labels := []string{s.SiteName, s.Mac, s.Model, s.Name, s.Serial, s.SiteID,
 		s.Type, s.Version, s.DeviceID, s.IP}
 	labelWan := append([]string{"all"}, labels...)
+	//	r.wait.Add(1) // closed by channel receiver.
 
 	// Gateway System Data.
 	return append([]*metricExports{

promunifi/usw.go

@@ -136,11 +136,10 @@ func descUSW(ns string) *usw {
 	}
 }
 
-func (u *unifiCollector) exportUSWs(usws []*unifi.USW) (e []*metricExports) {
+func (u *unifiCollector) exportUSWs(usws []*unifi.USW, ch chan []*metricExports) {
 	for _, sw := range usws {
-		e = append(e, u.exportUSW(sw)...)
+		ch <- u.exportUSW(sw)
 	}
-	return
 }
 
 // exportUSW exports Network Switch Data