fix: otel not working without USER

pkg/observability/metrics/datadog.go

@@ -0,0 +1,174 @@
+package metrics
+
+import (
+	"context"
+	"net"
+	"strings"
+	"time"
+
+	"github.com/go-kit/kit/metrics/dogstatsd"
+	"github.com/go-kit/kit/util/conn"
+	gokitlog "github.com/go-kit/log"
+	"github.com/rs/zerolog/log"
+	"github.com/traefik/traefik/v3/pkg/observability/logs"
+	otypes "github.com/traefik/traefik/v3/pkg/observability/types"
+	"github.com/traefik/traefik/v3/pkg/safe"
+)
+
+const (
+	unixAddressPrefix         = "unix://"
+	unixAddressDatagramPrefix = "unixgram://"
+	unixAddressStreamPrefix   = "unixstream://"
+)
+
+var (
+	datadogClient         *dogstatsd.Dogstatsd
+	datadogLoopCancelFunc context.CancelFunc
+)
+
+// Metric names consistent with https://github.com/DataDog/integrations-extras/pull/64
+const (
+	ddConfigReloadsName           = "config.reload.total"
+	ddLastConfigReloadSuccessName = "config.reload.lastSuccessTimestamp"
+	ddOpenConnsName               = "open.connections"
+
+	ddTLSCertsNotAfterTimestampName = "tls.certs.notAfterTimestamp"
+
+	ddEntryPointReqsName        = "entrypoint.request.total"
+	ddEntryPointReqsTLSName     = "entrypoint.request.tls.total"
+	ddEntryPointReqDurationName = "entrypoint.request.duration"
+	ddEntryPointReqsBytesName   = "entrypoint.requests.bytes.total"
+	ddEntryPointRespsBytesName  = "entrypoint.responses.bytes.total"
+
+	ddRouterReqsName         = "router.request.total"
+	ddRouterReqsTLSName      = "router.request.tls.total"
+	ddRouterReqsDurationName = "router.request.duration"
+	ddRouterReqsBytesName    = "router.requests.bytes.total"
+	ddRouterRespsBytesName   = "router.responses.bytes.total"
+
+	ddServiceReqsName         = "service.request.total"
+	ddServiceReqsTLSName      = "service.request.tls.total"
+	ddServiceReqsDurationName = "service.request.duration"
+	ddServiceRetriesName      = "service.retries.total"
+	ddServiceServerUpName     = "service.server.up"
+	ddServiceReqsBytesName    = "service.requests.bytes.total"
+	ddServiceRespsBytesName   = "service.responses.bytes.total"
+)
+
+// RegisterDatadog registers the metrics pusher if this didn't happen yet and creates a datadog Registry instance.
+func RegisterDatadog(ctx context.Context, config *otypes.Datadog) Registry {
+	// Ensures there is only one DataDog client sending metrics at any given time.
+	StopDatadog()
+
+	// just to be sure there is a prefix defined
+	if config.Prefix == "" {
+		config.Prefix = defaultMetricsPrefix
+	}
+
+	datadogLogger := logs.NewGoKitWrapper(log.Logger.With().Str(logs.MetricsProviderName, "datadog").Logger())
+	datadogClient = dogstatsd.New(config.Prefix+".", datadogLogger)
+
+	initDatadogClient(ctx, config, datadogLogger)
+
+	registry := &standardRegistry{
+		configReloadsCounter:           datadogClient.NewCounter(ddConfigReloadsName, 1.0),
+		lastConfigReloadSuccessGauge:   datadogClient.NewGauge(ddLastConfigReloadSuccessName),
+		openConnectionsGauge:           datadogClient.NewGauge(ddOpenConnsName),
+		tlsCertsNotAfterTimestampGauge: datadogClient.NewGauge(ddTLSCertsNotAfterTimestampName),
+	}
+
+	if config.AddEntryPointsLabels {
+		registry.epEnabled = config.AddEntryPointsLabels
+		registry.entryPointReqsCounter = NewCounterWithNoopHeaders(datadogClient.NewCounter(ddEntryPointReqsName, 1.0))
+		registry.entryPointReqsTLSCounter = datadogClient.NewCounter(ddEntryPointReqsTLSName, 1.0)
+		registry.entryPointReqDurationHistogram, _ = NewHistogramWithScale(datadogClient.NewHistogram(ddEntryPointReqDurationName, 1.0), time.Second)
+		registry.entryPointReqsBytesCounter = datadogClient.NewCounter(ddEntryPointReqsBytesName, 1.0)
+		registry.entryPointRespsBytesCounter = datadogClient.NewCounter(ddEntryPointRespsBytesName, 1.0)
+	}
+
+	if config.AddRoutersLabels {
+		registry.routerEnabled = config.AddRoutersLabels
+		registry.routerReqsCounter = NewCounterWithNoopHeaders(datadogClient.NewCounter(ddRouterReqsName, 1.0))
+		registry.routerReqsTLSCounter = datadogClient.NewCounter(ddRouterReqsTLSName, 1.0)
+		registry.routerReqDurationHistogram, _ = NewHistogramWithScale(datadogClient.NewHistogram(ddRouterReqsDurationName, 1.0), time.Second)
+		registry.routerReqsBytesCounter = datadogClient.NewCounter(ddRouterReqsBytesName, 1.0)
+		registry.routerRespsBytesCounter = datadogClient.NewCounter(ddRouterRespsBytesName, 1.0)
+	}
+
+	if config.AddServicesLabels {
+		registry.svcEnabled = config.AddServicesLabels
+		registry.serviceReqsCounter = NewCounterWithNoopHeaders(datadogClient.NewCounter(ddServiceReqsName, 1.0))
+		registry.serviceReqsTLSCounter = datadogClient.NewCounter(ddServiceReqsTLSName, 1.0)
+		registry.serviceReqDurationHistogram, _ = NewHistogramWithScale(datadogClient.NewHistogram(ddServiceReqsDurationName, 1.0), time.Second)
+		registry.serviceRetriesCounter = datadogClient.NewCounter(ddServiceRetriesName, 1.0)
+		registry.serviceServerUpGauge = datadogClient.NewGauge(ddServiceServerUpName)
+		registry.serviceReqsBytesCounter = datadogClient.NewCounter(ddServiceReqsBytesName, 1.0)
+		registry.serviceRespsBytesCounter = datadogClient.NewCounter(ddServiceRespsBytesName, 1.0)
+	}
+
+	return registry
+}
+
+func initDatadogClient(ctx context.Context, config *otypes.Datadog, logger gokitlog.LoggerFunc) {
+	network, address := parseDatadogAddress(config.Address)
+
+	ctx, datadogLoopCancelFunc = context.WithCancel(ctx)
+
+	safe.Go(func() {
+		ticker := time.NewTicker(time.Duration(config.PushInterval))
+		defer ticker.Stop()
+
+		dialer := func(network, address string) (net.Conn, error) {
+			switch network {
+			case "unix":
+				// To mimic the Datadog client when the network is unix we will try to guess the UDS type.
+				newConn, err := net.Dial("unixgram", address)
+				if err != nil && strings.Contains(err.Error(), "protocol wrong type for socket") {
+					return net.Dial("unix", address)
+				}
+				return newConn, err
+
+			case "unixgram":
+				return net.Dial("unixgram", address)
+
+			case "unixstream":
+				return net.Dial("unix", address)
+
+			default:
+				return net.Dial(network, address)
+			}
+		}
+		datadogClient.WriteLoop(ctx, ticker.C, conn.NewManager(dialer, network, address, time.After, logger))
+	})
+}
+
+// StopDatadog stops the Datadog metrics pusher.
+func StopDatadog() {
+	if datadogLoopCancelFunc != nil {
+		datadogLoopCancelFunc()
+		datadogLoopCancelFunc = nil
+	}
+}
+
+func parseDatadogAddress(address string) (string, string) {
+	network := "udp"
+
+	var addr string
+	switch {
+	case strings.HasPrefix(address, unixAddressPrefix):
+		network = "unix"
+		addr = address[len(unixAddressPrefix):]
+	case strings.HasPrefix(address, unixAddressDatagramPrefix):
+		network = "unixgram"
+		addr = address[len(unixAddressDatagramPrefix):]
+	case strings.HasPrefix(address, unixAddressStreamPrefix):
+		network = "unixstream"
+		addr = address[len(unixAddressStreamPrefix):]
+	case address != "":
+		addr = address
+	default:
+		addr = "localhost:8125"
+	}
+
+	return network, addr
+}