Add NegControllerErrorCount metrics

Add NegControllerErrorCount metrics to track the count of all errors
from NEG controller, and counts of server errors from GCE/K8s.

pkg/neg/controller.go

@@ -710,6 +710,7 @@ func (c *Controller) handleErr(err error, key interface{}) {
 	}
 
 	msg := fmt.Sprintf("error processing service %q: %v", key, err)
+	metrics.PublishNegControllerErrorCountMetrics(err)
 	c.logger.Error(nil, msg)
 	if service, exists, err := c.serviceLister.GetByKey(key.(string)); err != nil {
 		c.logger.Error(err, "Failed to retrieve service from store", "service", key.(string))

pkg/neg/metrics/metrics.go

@@ -21,6 +21,7 @@ import (
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"k8s.io/ingress-gce/pkg/utils"
 )
 
 const (
@@ -49,6 +50,10 @@ const (
 	ipv6EndpointType      = "IPv6"
 	dualStackEndpointType = "DualStack"
 	migrationEndpointType = "Migration"
+
+	gceServerError          = "GCE_server_error"
+	k8sServerError          = "K8s_server_error"
+	totalNegControllerError = "total_neg_controller_error"
 )
 
 type syncType string
@@ -211,6 +216,16 @@ var (
 		},
 		[]string{"endpoint_type"},
 	)
+
+	// NegControllerErrorCount tracks the count for internal sync errors and server error(GCE/K8s)
+	NegControllerErrorCount = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Subsystem: negControllerSubsystem,
+			Name:      "neg_controller_error_count",
+			Help:      "Current count for each sync result",
+		},
+		[]string{"error_type"},
+	)
 )
 
 var register sync.Once
@@ -234,6 +249,7 @@ func RegisterMetrics() {
 		prometheus.MustRegister(DualStackMigrationLongestUnfinishedDuration)
 		prometheus.MustRegister(DualStackMigrationServiceCount)
 		prometheus.MustRegister(SyncerCountByEndpointType)
+		prometheus.MustRegister(NegControllerErrorCount)
 
 		RegisterSyncerMetrics()
 	})
@@ -279,6 +295,21 @@ func PublishDegradedModeCorrectnessMetrics(count int, endpointType string, negTy
 	DegradeModeCorrectness.WithLabelValues(negType, endpointType).Observe(float64(count))
 }
 
+// PublishNegControllerErrorCountMetrics publishes collected metrics
+// for neg controller errors.
+func PublishNegControllerErrorCountMetrics(err error) {
+	if err == nil {
+		return
+	}
+	NegControllerErrorCount.WithLabelValues(totalNegControllerError).Inc()
+	if utils.IsGCEServerError(err) {
+		NegControllerErrorCount.WithLabelValues(gceServerError).Inc()
+	}
+	if utils.IsK8sServerError(err) {
+		NegControllerErrorCount.WithLabelValues(k8sServerError).Inc()
+	}
+}
+
 func getResult(err error) string {
 	if err != nil {
 		return resultError

pkg/utils/utils.go

@@ -268,6 +268,40 @@ func GetErrorType(err error) string {
 	return ""
 }
 
+// IsGCEServerError returns true if the error is GCE server error
+func IsGCEServerError(err error) bool {
+	if err == nil {
+		return false
+	}
+	var gerr *googleapi.Error
+	if !errors.As(err, &gerr) {
+		return false
+	}
+	for {
+		if apiErr, ok := err.(*googleapi.Error); ok {
+			return apiErr.Code >= http.StatusInternalServerError
+		}
+		err = errors.Unwrap(err)
+	}
+}
+
+// IsK8sServerError returns true if the error is K8s server error
+func IsK8sServerError(err error) bool {
+	if err == nil {
+		return false
+	}
+	var k8serr *k8serrors.StatusError
+	if !errors.As(err, &k8serr) {
+		return false
+	}
+	for {
+		if apiErr, ok := err.(*k8serrors.StatusError); ok {
+			return apiErr.ErrStatus.Code >= http.StatusInternalServerError
+		}
+		err = errors.Unwrap(err)
+	}
+}
+
 // PrettyJson marshals an object in a human-friendly format.
 func PrettyJson(data interface{}) (string, error) {
 	buffer := new(bytes.Buffer)