fix: version skew compatibility for managed kubernetes providers

pkg/descheduler/descheduler.go

@@ -21,8 +21,6 @@ import (
 	"errors"
 	"fmt"
 	"math"
-	"strconv"
-	"strings"
 	"time"
 
 	"go.opentelemetry.io/otel/attribute"
@@ -38,6 +36,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime"
+	utilversion "k8s.io/apimachinery/pkg/util/version"
 	"k8s.io/apimachinery/pkg/util/wait"
 	clientset "k8s.io/client-go/kubernetes"
 	fakeclientset "k8s.io/client-go/kubernetes/fake"
@@ -277,29 +276,29 @@ func Run(ctx context.Context, rs *options.DeschedulerServer) error {
 }
 
 func validateVersionCompatibility(discovery discovery.DiscoveryInterface, versionInfo version.Info) error {
-	serverVersion, serverErr := discovery.ServerVersion()
-	if serverErr != nil {
-		return errors.New("failed to get Kubernetes server version")
+	serverVersionInfo, err := discovery.ServerVersion()
+	if err != nil {
+		return errors.New("failed to discover Kubernetes server version")
 	}
 
-	deschedulerMinorVersion := strings.Split(versionInfo.Minor, ".")[0]
-	deschedulerMinorVersionFloat, err := strconv.ParseFloat(deschedulerMinorVersion, 64)
+	serverVersion, err := utilversion.ParseSemantic(serverVersionInfo.String())
+	if err != nil {
+		return errors.New("failed to parse Kubernetes server version")
+	}
+
+	deschedulerVersion, err := utilversion.ParseGeneric(versionInfo.GitVersion)
 	if err != nil {
 		return errors.New("failed to convert Descheduler minor version to float")
 	}
 
-	kubernetesMinorVersionFloat, err := strconv.ParseFloat(serverVersion.Minor, 64)
-	if err != nil {
-		return errors.New("failed to convert Kubernetes server minor version to float")
-	}
-
-	if math.Abs(deschedulerMinorVersionFloat-kubernetesMinorVersionFloat) > 3 {
+	deschedulerMinor := float64(deschedulerVersion.Minor())
+	serverMinor := float64(serverVersion.Minor())
+	if math.Abs(deschedulerMinor-serverMinor) > 3 {
 		return fmt.Errorf(
-			"descheduler minor version %v is not supported on your version of Kubernetes %v.%v. "+
+			"descheduler version %v may not be supported on your version of Kubernetes %v."+
 				"See compatibility docs for more info: https://github.com/kubernetes-sigs/descheduler#compatibility-matrix",
-			deschedulerMinorVersion,
-			serverVersion.Major,
-			serverVersion.Minor,
+			deschedulerVersion.String(),
+			serverVersionInfo.String(),
 		)
 	}
 

pkg/descheduler/descheduler_test.go

@@ -250,49 +250,55 @@ func TestRootCancelWithNoInterval(t *testing.T) {
 
 func TestValidateVersionCompatibility(t *testing.T) {
 	type testCase struct {
-		name             string
-		deschedulerMinor string
-		serverMinor      string
-		expectError      bool
+		name               string
+		deschedulerVersion string
+		serverVersion      string
+		expectError        bool
 	}
 	testCases := []testCase{
 		{
-			name:             "no error when descheduler minor equals to server minor",
-			deschedulerMinor: "26.0",
-			serverMinor:      "26",
-			expectError:      false,
+			name:               "no error when descheduler minor equals to server minor",
+			deschedulerVersion: "v0.26",
+			serverVersion:      "v1.26.1",
+			expectError:        false,
 		},
 		{
-			name:             "no error when descheduler minor is 3 behind server minor",
-			deschedulerMinor: "23.0",
-			serverMinor:      "26",
-			expectError:      false,
+			name:               "no error when descheduler minor is 3 behind server minor",
+			deschedulerVersion: "0.23",
+			serverVersion:      "v1.26.1",
+			expectError:        false,
 		},
 		{
-			name:             "no error when descheduler minor is 3 ahead of server minor",
-			deschedulerMinor: "26.0",
-			serverMinor:      "23",
-			expectError:      false,
+			name:               "no error when descheduler minor is 3 ahead of server minor",
+			deschedulerVersion: "v0.26",
+			serverVersion:      "v1.26.1",
+			expectError:        false,
 		},
 		{
-			name:             "error when descheduler minor is 4 behind server minor",
-			deschedulerMinor: "22.0",
-			serverMinor:      "26",
-			expectError:      true,
+			name:               "error when descheduler minor is 4 behind server minor",
+			deschedulerVersion: "v0.22",
+			serverVersion:      "v1.26.1",
+			expectError:        true,
 		},
 		{
-			name:             "error when descheduler minor is 4 ahead of server minor",
-			deschedulerMinor: "27.0",
-			serverMinor:      "23",
-			expectError:      true,
+			name:               "error when descheduler minor is 4 ahead of server minor",
+			deschedulerVersion: "v0.27",
+			serverVersion:      "v1.23.1",
+			expectError:        true,
+		},
+		{
+			name:               "no error when using managed provider version",
+			deschedulerVersion: "v0.25",
+			serverVersion:      "v1.25.12-eks-2d98532",
+			expectError:        false,
 		},
 	}
 	client := fakeclientset.NewSimpleClientset()
 	fakeDiscovery, _ := client.Discovery().(*fakediscovery.FakeDiscovery)
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			fakeDiscovery.FakedServerVersion = &apiversion.Info{Major: "1", Minor: tc.serverMinor}
-			deschedulerVersion := deschedulerversion.Info{Major: "0", Minor: tc.deschedulerMinor}
+			fakeDiscovery.FakedServerVersion = &apiversion.Info{GitVersion: tc.serverVersion}
+			deschedulerVersion := deschedulerversion.Info{GitVersion: tc.deschedulerVersion}
 			err := validateVersionCompatibility(fakeDiscovery, deschedulerVersion)
 
 			hasError := err != nil