Implement integration with statsd

main.go

@@ -158,7 +158,9 @@ func main() {
 		zap.S().Infow("Use direct connection to Telegram")
 	}
 
-	go stats.Start(conf)
+	if err := stats.Start(conf); err != nil {
+		panic(err)
+	}
 
 	server := proxy.NewProxy(conf)
 	if err := server.Serve(); err != nil {

stats/server.go

@@ -14,7 +14,7 @@ import (
 var instance *stats
 
 // Start starts new statisitcs server.
-func Start(conf *config.Config) {
+func Start(conf *config.Config) error {
 	log := zap.S().Named("stats")
 
 	instance = &stats{
@@ -23,6 +23,14 @@ func Start(conf *config.Config) {
 		mutex:  &sync.RWMutex{},
 	}
 
+	if conf.StatsD.Enabled {
+		client, err := newStatsd(conf)
+		if err != nil {
+			return err
+		}
+		go client.run()
+	}
+
 	go crashManager()
 	go connectionManager()
 	go trafficManager()
@@ -51,7 +59,11 @@ func Start(conf *config.Config) {
 		}
 	})
 
-	if err := http.ListenAndServe(conf.StatAddr(), nil); err != nil {
-		log.Fatalw("Stats server has been stopped", "error", err)
-	}
+	go func() {
+		if err := http.ListenAndServe(conf.StatAddr(), nil); err != nil {
+			log.Fatalw("Stats server has been stopped", "error", err)
+		}
+	}()
+
+	return nil
 }

stats/statsd.go

@@ -0,0 +1,79 @@
+package stats
+
+import (
+	"time"
+
+	"github.com/juju/errors"
+	statsd "gopkg.in/alexcesaro/statsd.v2"
+
+	"github.com/9seconds/mtg/config"
+)
+
+const (
+	statsdConnectionsAbridgedV4 = "connections.abridged.ipv4"
+	statsdConnectionsAbridgedV6 = "connections.abridged.ipv6"
+
+	statsdConnectionsIntermediateV4 = "connections.intermediate.ipv4"
+	statsdConnectionsIntermediateV6 = "connections.intermediate.ipv6"
+
+	statsdConnectionsSecureV4 = "connections.secure.ipv4"
+	statsdConnectionsSecureV6 = "connections.secure.ipv6"
+
+	statsdTrafficIngress = "traffic.ingress"
+	statsdTrafficEgress  = "traffic.egress"
+
+	statsdSpeedIngress = "speed.ingress"
+	statsdSpeedEgress  = "speed.egress"
+
+	statsdCrashes = "crashes"
+)
+
+const statsdPollTime = time.Second
+
+type statsdExporter struct {
+	client *statsd.Client
+}
+
+func (s *statsdExporter) run() {
+	for range time.Tick(statsdPollTime) {
+		instance.mutex.Lock()
+
+		s.client.Gauge(statsdConnectionsAbridgedV4, instance.Connections.Abridged.IPv4)
+		s.client.Gauge(statsdConnectionsAbridgedV6, instance.Connections.Abridged.IPv6)
+		s.client.Gauge(statsdConnectionsIntermediateV4, instance.Connections.Intermediate.IPv4)
+		s.client.Gauge(statsdConnectionsIntermediateV6, instance.Connections.Intermediate.IPv6)
+		s.client.Gauge(statsdConnectionsSecureV4, instance.Connections.Secure.IPv4)
+		s.client.Gauge(statsdConnectionsSecureV6, instance.Connections.Secure.IPv6)
+		s.client.Gauge(statsdTrafficIngress, uint64(instance.Traffic.Ingress))
+		s.client.Gauge(statsdTrafficEgress, uint64(instance.Traffic.Egress))
+		s.client.Gauge(statsdSpeedIngress, uint64(instance.Speed.Ingress))
+		s.client.Gauge(statsdSpeedEgress, uint64(instance.Speed.Egress))
+		s.client.Gauge(statsdCrashes, instance.Crashes)
+
+		instance.mutex.Unlock()
+	}
+}
+
+func newStatsd(conf *config.Config) (*statsdExporter, error) {
+	options := []statsd.Option{
+		statsd.Network(conf.StatsD.Addr.Network()),
+		statsd.Address(conf.StatsD.Addr.String()),
+		statsd.Prefix(conf.StatsD.Prefix),
+	}
+
+	if conf.StatsD.TagsFormat > 0 {
+		options = append(options, statsd.TagsFormat(conf.StatsD.TagsFormat))
+		tags := make([]string, len(conf.StatsD.Tags)*2)
+		for k, v := range conf.StatsD.Tags {
+			tags = append(tags, k, v)
+		}
+		options = append(options, statsd.Tags(tags...))
+	}
+
+	client, err := statsd.New(options...)
+	if err != nil {
+		return nil, errors.Annotate(err, "Cannot create statsd client")
+	}
+
+	return &statsdExporter{client: client}, nil
+}