feat: add metrics instrumentations for status updater

Signed-off-by: bitliu <bitliu@tencent.com>

internal/status/metrics.go

@@ -0,0 +1,19 @@
+// Copyright Envoy Gateway Authors
+// SPDX-License-Identifier: Apache-2.0
+// The full text of the Apache license is available in the LICENSE file at
+// the root of the repo.
+
+package status
+
+import "github.com/envoyproxy/gateway/internal/metrics"
+
+var (
+	statusUpdateTotal           = metrics.NewCounter("status_update_total", "Total number of status updates by object kind.")
+	statusUpdateFailed          = metrics.NewCounter("status_update_failed_total", "Number of status updates that failed by object kind.")
+	statusUpdateConflict        = metrics.NewCounter("status_update_conflict_total", "Number of status update conflicts encountered by object kind.")
+	statusUpdateSuccess         = metrics.NewCounter("status_update_success_total", "Number of status updates that succeeded by object kind.")
+	statusUpdateNoop            = metrics.NewCounter("status_update_noop_total", "Number of status updates that are no-ops by object kind. This is a subset of successful status updates.")
+	statusUpdateDurationSeconds = metrics.NewHistogram("status_update_duration_seconds", "How long a status update takes to finish.", []float64{0.001, 0.01, 0.1, 1, 5, 10})
+
+	kindLabel = metrics.NewLabel("kind")
+)

internal/status/status.go

@@ -15,6 +15,7 @@ package status
 
 import (
 	"context"
+	"time"
 
 	"github.com/go-logr/logr"
 	"github.com/google/go-cmp/cmp"
@@ -73,9 +74,32 @@ func NewUpdateHandler(log logr.Logger, client client.Client) *UpdateHandler {
 }
 
 func (u *UpdateHandler) apply(update Update) {
-	if err := retry.RetryOnConflict(retry.DefaultBackoff, func() error {
-		obj := update.Resource
+	var statusUpdateErr error
+	obj := update.Resource
+	objKind := kindOf(obj)
 
+	startTime := time.Now()
+
+	statusUpdateTotal.With(kindLabel.Value(objKind)).Increment()
+
+	defer func() {
+		updateDuration := time.Since(startTime)
+		if statusUpdateErr != nil {
+			statusUpdateDurationSeconds.With(kindLabel.Value(objKind)).Record(updateDuration.Seconds())
+			statusUpdateFailed.With(kindLabel.Value(objKind)).Increment()
+		} else {
+			statusUpdateDurationSeconds.With(kindLabel.Value(objKind)).Record(updateDuration.Seconds())
+			statusUpdateSuccess.With(kindLabel.Value(objKind)).Increment()
+		}
+	}()
+
+	if statusUpdateErr = retry.OnError(retry.DefaultBackoff, func(err error) bool {
+		if kerrors.IsConflict(err) {
+			statusUpdateConflict.With(kindLabel.Value(objKind)).Increment()
+			return true
+		}
+		return false
+	}, func() error {
 		// Get the resource.
 		if err := u.client.Get(context.Background(), update.NamespacedName, obj); err != nil {
 			if kerrors.IsNotFound(err) {
@@ -90,14 +114,15 @@ func (u *UpdateHandler) apply(update Update) {
 			u.log.WithName(update.NamespacedName.Name).
 				WithName(update.NamespacedName.Namespace).
 				Info("status unchanged, bypassing update")
+			statusUpdateNoop.With(kindLabel.Value(objKind)).Increment()
 			return nil
 		}
 
 		newObj.SetUID(obj.GetUID())
 
 		return u.client.Status().Update(context.Background(), newObj)
-	}); err != nil {
-		u.log.Error(err, "unable to update status", "name", update.NamespacedName.Name,
+	}); statusUpdateErr != nil {
+		u.log.Error(statusUpdateErr, "unable to update status", "name", update.NamespacedName.Name,
 			"namespace", update.NamespacedName.Namespace)
 	}
 }
@@ -169,6 +194,7 @@ func (u *UpdateWriter) Send(update Update) {
 //	GRPCRoute
 //	EnvoyPatchPolicy
 //	ClientTrafficPolicy
+//	SecurityPolicy
 func isStatusEqual(objA, objB interface{}) bool {
 	opts := cmpopts.IgnoreFields(metav1.Condition{}, "LastTransitionTime")
 	switch a := objA.(type) {
@@ -232,7 +258,43 @@ func isStatusEqual(objA, objB interface{}) bool {
 				return true
 			}
 		}
+	case *egv1a1.SecurityPolicy:
+		if b, ok := objB.(*egv1a1.SecurityPolicy); ok {
+			if cmp.Equal(a.Status, b.Status, opts) {
+				return true
+			}
+		}
 	}
 
 	return false
 }
+
+// kindOf returns the kind string for the given Kubernetes object.
+func kindOf(obj interface{}) string {
+	switch obj.(type) {
+	case *gwapiv1.GatewayClass:
+		return "GatewayClass"
+	case *gwapiv1.Gateway:
+		return "Gateway"
+	case *gwapiv1.HTTPRoute:
+		return "HTTPRoute"
+	case *gwapiv1a2.TLSRoute:
+		return "TLSRoute"
+	case *gwapiv1a2.TCPRoute:
+		return "TCPRoute"
+	case *gwapiv1a2.UDPRoute:
+		return "UDPRoute"
+	case *gwapiv1a2.GRPCRoute:
+		return "GRPCRoute"
+	case *egv1a1.EnvoyPatchPolicy:
+		return "EnvoyPatchPolicy"
+	case *egv1a1.ClientTrafficPolicy:
+		return "ClientTrafficPolicy"
+	case *egv1a1.BackendTrafficPolicy:
+		return "BackendTrafficPolicy"
+	case *egv1a1.SecurityPolicy:
+		return "SecurityPolicy"
+	}
+
+	return ""
+}