Skip no-op updates in eksctl utils update-authentication-mode

pkg/ctl/utils/export_test.go

@@ -3,3 +3,5 @@ package utils
 func ValidateLoggingFlags(toEnable, toDisable []string) error {
 	return validateLoggingFlags(toEnable, toDisable)
 }
+
+var UpdateAuthenticationModeForCluster = updateAuthenticationModeForCluster

pkg/ctl/utils/update_authentication_mode.go

@@ -13,6 +13,7 @@ import (
 
 	api "github.com/weaveworks/eksctl/pkg/apis/eksctl.io/v1alpha5"
 	"github.com/weaveworks/eksctl/pkg/ctl/cmdutils"
+	"github.com/weaveworks/eksctl/pkg/eks"
 	"github.com/weaveworks/eksctl/pkg/eks/waiter"
 )
 
@@ -51,12 +52,23 @@ func doUpdateAuthenticationMode(cmd *cmdutils.Cmd, authenticationMode string) er
 		return err
 	}
 
+	return updateAuthenticationModeForCluster(ctx, clusterProvider, cmd.ClusterConfig)
+}
+
+func updateAuthenticationModeForCluster(ctx context.Context, clusterProvider *eks.ClusterProvider, clusterConfig *api.ClusterConfig) error {
+	authenticationMode := clusterConfig.AccessConfig.AuthenticationMode
+	clusterName := clusterConfig.Metadata.Name
+
+	if cluster := clusterProvider.GetClusterState(); cluster.AccessConfig != nil && cluster.AccessConfig.AuthenticationMode == authenticationMode {
+		logger.Info("authentication mode is already %s on cluster %s, skipping update", authenticationMode, clusterName)
+		return nil
+	}
+
 	logger.Info("setting cluster's authentication mode to %s", authenticationMode)
-	clusterName := cmd.ClusterConfig.Metadata.Name
 	output, err := clusterProvider.AWSProvider.EKS().UpdateClusterConfig(ctx, &awseks.UpdateClusterConfigInput{
 		Name: &clusterName,
 		AccessConfig: &ekstypes.UpdateAccessConfigRequest{
-			AuthenticationMode: cmd.ClusterConfig.AccessConfig.AuthenticationMode,
+			AuthenticationMode: authenticationMode,
 		},
 	})
 	if err != nil {
@@ -79,7 +91,7 @@ func doUpdateAuthenticationMode(cmd *cmdutils.Cmd, authenticationMode string) er
 		return fmt.Errorf("failed to update cluster authentication mode: %s", e.UpdateError)
 
 	case nil:
-		logger.Info("authentication mode was successfully updated to %s on cluster %s", cmd.ClusterConfig.AccessConfig.AuthenticationMode, clusterName)
+		logger.Info("authentication mode was successfully updated to %s on cluster %s", authenticationMode, clusterName)
 		return nil
 
 	default:

pkg/ctl/utils/update_authentication_mode_test.go

@@ -1,8 +1,19 @@
 package utils_test
 
 import (
+	"context"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	awseks "github.com/aws/aws-sdk-go-v2/service/eks"
+	ekstypes "github.com/aws/aws-sdk-go-v2/service/eks/types"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
+	"github.com/stretchr/testify/mock"
+
+	api "github.com/weaveworks/eksctl/pkg/apis/eksctl.io/v1alpha5"
+	"github.com/weaveworks/eksctl/pkg/ctl/utils"
+	"github.com/weaveworks/eksctl/pkg/eks"
+	"github.com/weaveworks/eksctl/pkg/testutils/mockprovider"
 )
 
 var _ = Describe("update authentication mode", func() {
@@ -37,4 +48,70 @@ var _ = Describe("update authentication mode", func() {
 			args:        []string{"--authentication-mode", "CONFIG_MAP", "--config-file", "../../../examples/01-simple-cluster.yaml"},
 		}),
 	)
+
+	Describe("updating the cluster", func() {
+		const clusterName = "test"
+
+		makeClusterProvider := func(currentMode ekstypes.AuthenticationMode) (*mockprovider.MockProvider, *eks.ClusterProvider) {
+			provider := mockprovider.NewMockProvider()
+			return provider, &eks.ClusterProvider{
+				AWSProvider: provider,
+				Status: &eks.ProviderStatus{
+					ClusterInfo: &eks.ClusterInfo{
+						Cluster: &ekstypes.Cluster{
+							Name: aws.String(clusterName),
+							AccessConfig: &ekstypes.AccessConfigResponse{
+								AuthenticationMode: currentMode,
+							},
+						},
+					},
+				},
+			}
+		}
+
+		makeClusterConfig := func(desiredMode ekstypes.AuthenticationMode) *api.ClusterConfig {
+			clusterConfig := api.NewClusterConfig()
+			clusterConfig.Metadata.Name = clusterName
+			clusterConfig.AccessConfig.AuthenticationMode = desiredMode
+			return clusterConfig
+		}
+
+		When("the cluster already has the desired authentication mode", func() {
+			It("skips the update", func() {
+				provider, clusterProvider := makeClusterProvider(ekstypes.AuthenticationModeApiAndConfigMap)
+
+				err := utils.UpdateAuthenticationModeForCluster(context.Background(), clusterProvider, makeClusterConfig(ekstypes.AuthenticationModeApiAndConfigMap))
+				Expect(err).NotTo(HaveOccurred())
+				provider.MockEKS().AssertNotCalled(GinkgoT(), "UpdateClusterConfig", mock.Anything, mock.Anything)
+			})
+		})
+
+		When("the cluster has a different authentication mode", func() {
+			It("updates the cluster with the desired mode", func() {
+				provider, clusterProvider := makeClusterProvider(ekstypes.AuthenticationModeConfigMap)
+
+				updateID := aws.String("update-1")
+				provider.MockEKS().On("UpdateClusterConfig", mock.Anything, mock.MatchedBy(func(input *awseks.UpdateClusterConfigInput) bool {
+					return *input.Name == clusterName && input.AccessConfig.AuthenticationMode == ekstypes.AuthenticationModeApiAndConfigMap
+				})).Return(&awseks.UpdateClusterConfigOutput{
+					Update: &ekstypes.Update{
+						Id: updateID,
+					},
+				}, nil).Once()
+				provider.MockEKS().On("DescribeUpdate", mock.Anything, mock.MatchedBy(func(input *awseks.DescribeUpdateInput) bool {
+					return *input.UpdateId == *updateID
+				}), mock.Anything).Return(&awseks.DescribeUpdateOutput{
+					Update: &ekstypes.Update{
+						Id:     updateID,
+						Type:   ekstypes.UpdateTypeAccessConfigUpdate,
+						Status: ekstypes.UpdateStatusSuccessful,
+					},
+				}, nil).Once()
+
+				err := utils.UpdateAuthenticationModeForCluster(context.Background(), clusterProvider, makeClusterConfig(ekstypes.AuthenticationModeApiAndConfigMap))
+				Expect(err).NotTo(HaveOccurred())
+				provider.MockEKS().AssertExpectations(GinkgoT())
+			})
+		})
+	})
 })