fix: Lower casing disruption count metric on reason label (#1862)

pkg/controllers/disruption/orchestration/queue.go

@@ -44,6 +44,7 @@ import (
 	"sigs.k8s.io/karpenter/pkg/events"
 	"sigs.k8s.io/karpenter/pkg/metrics"
 	"sigs.k8s.io/karpenter/pkg/operator/injection"
+	"sigs.k8s.io/karpenter/pkg/utils/pretty"
 )
 
 const (
@@ -196,7 +197,7 @@ func (q *Queue) Reconcile(ctx context.Context) (reconcile.Result, error) {
 		})
 		DisruptionQueueFailuresTotal.Add(float64(len(failedLaunches)), map[string]string{
 			decisionLabel:          cmd.Decision(),
-			metrics.ReasonLabel:    string(cmd.reason),
+			metrics.ReasonLabel:    pretty.ToSnakeCase(string(cmd.reason)),
 			consolidationTypeLabel: cmd.consolidationType,
 		})
 		multiErr := multierr.Combine(err, cmd.lastError, state.RequireNoScheduleTaint(ctx, q.kubeClient, false, cmd.candidates...))
@@ -265,7 +266,7 @@ func (q *Queue) waitOrTerminate(ctx context.Context, cmd *Command) error {
 			multiErr = multierr.Append(multiErr, client.IgnoreNotFound(err))
 		} else {
 			metrics.NodeClaimsDisruptedTotal.Inc(map[string]string{
-				metrics.ReasonLabel:       string(cmd.reason),
+				metrics.ReasonLabel:       pretty.ToSnakeCase(string(cmd.reason)),
 				metrics.NodePoolLabel:     cmd.candidates[i].NodeClaim.Labels[v1.NodePoolLabelKey],
 				metrics.CapacityTypeLabel: cmd.candidates[i].NodeClaim.Labels[v1.CapacityTypeLabelKey],
 			})

pkg/controllers/node/health/controller.go

@@ -41,6 +41,7 @@ import (
 	"sigs.k8s.io/karpenter/pkg/metrics"
 	"sigs.k8s.io/karpenter/pkg/operator/injection"
 	nodeutils "sigs.k8s.io/karpenter/pkg/utils/node"
+	"sigs.k8s.io/karpenter/pkg/utils/pretty"
 )
 
 var allowedUnhealthyPercent = intstr.FromString("20%")
@@ -126,7 +127,7 @@ func (c *Controller) Reconcile(ctx context.Context, node *corev1.Node) (reconcil
 	// The deletion timestamp has successfully been set for the Node, update relevant metrics.
 	log.FromContext(ctx).V(1).Info("deleting unhealthy node")
 	metrics.NodeClaimsDisruptedTotal.Inc(map[string]string{
-		metrics.ReasonLabel:       string(unhealthyNodeCondition.Type),
+		metrics.ReasonLabel:       pretty.ToSnakeCase(string(unhealthyNodeCondition.Type)),
 		metrics.NodePoolLabel:     node.Labels[v1.NodePoolLabelKey],
 		metrics.CapacityTypeLabel: node.Labels[v1.CapacityTypeLabelKey],
 	})

pkg/controllers/node/health/suite_test.go

@@ -38,6 +38,7 @@ import (
 	"sigs.k8s.io/karpenter/pkg/test"
 	. "sigs.k8s.io/karpenter/pkg/test/expectations"
 	"sigs.k8s.io/karpenter/pkg/test/v1alpha1"
+	"sigs.k8s.io/karpenter/pkg/utils/pretty"
 	. "sigs.k8s.io/karpenter/pkg/utils/testing"
 )
 
@@ -341,7 +342,7 @@ var _ = Describe("Node Health", func() {
 			Expect(nodeClaim.DeletionTimestamp).ToNot(BeNil())
 
 			ExpectMetricCounterValue(metrics.NodeClaimsDisruptedTotal, 1, map[string]string{
-				metrics.ReasonLabel:   string(cloudProvider.RepairPolicies()[0].ConditionType),
+				metrics.ReasonLabel:   pretty.ToSnakeCase(string(cloudProvider.RepairPolicies()[0].ConditionType)),
 				metrics.NodePoolLabel: nodePool.Name,
 			})
 		})

pkg/controllers/nodeclaim/expiration/controller.go

@@ -18,6 +18,7 @@ package expiration
 
 import (
 	"context"
+	"strings"
 	"time"
 
 	"k8s.io/utils/clock"
@@ -75,7 +76,7 @@ func (c *Controller) Reconcile(ctx context.Context, nodeClaim *v1.NodeClaim) (re
 	// 4. The deletion timestamp has successfully been set for the NodeClaim, update relevant metrics.
 	log.FromContext(ctx).V(1).Info("deleting expired nodeclaim")
 	metrics.NodeClaimsDisruptedTotal.Inc(map[string]string{
-		metrics.ReasonLabel:       metrics.ExpiredReason,
+		metrics.ReasonLabel:       strings.ToLower(metrics.ExpiredReason),
 		metrics.NodePoolLabel:     nodeClaim.Labels[v1.NodePoolLabelKey],
 		metrics.CapacityTypeLabel: nodeClaim.Labels[v1.CapacityTypeLabelKey],
 	})

pkg/utils/pretty/pretty.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"regexp"
 	"strings"
 
 	"golang.org/x/exp/constraints"
@@ -85,3 +86,12 @@ func Taint(t v1.Taint) string {
 	}
 	return fmt.Sprintf("%s=%s:%s", t.Key, t.Value, t.Effect)
 }
+
+var matchFirstCap = regexp.MustCompile("(.)([A-Z][a-z]+)")
+var matchAllCap = regexp.MustCompile("([a-z0-9])([A-Z])")
+
+func ToSnakeCase(str string) string {
+	snake := matchFirstCap.ReplaceAllString(str, "${1}_${2}")
+	snake = matchAllCap.ReplaceAllString(snake, "${1}_${2}")
+	return strings.ToLower(snake)
+}

pkg/utils/pretty/suite_test.go

@@ -0,0 +1,38 @@
+/*
+Copyright The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package pretty_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"sigs.k8s.io/karpenter/pkg/utils/pretty"
+)
+
+func TestOperator(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "Pretty Utils")
+}
+
+var _ = Describe("Pretty", func() {
+	It("should convert camel case to snake case", func() {
+		camelCase := "testKeyValue"
+		Expect(pretty.ToSnakeCase(camelCase)).To(Equal("test_key_value"))
+	})
+})