kubeadm: restructure upgradeVariables

Author: Dmitry Rozhkov

cmd/kubeadm/app/cmd/upgrade/apply.go

@@ -153,37 +153,37 @@ func runApply(flags *applyFlags) error {
 	// Start with the basics, verify that the cluster is healthy and get the configuration from the cluster (using the ConfigMap)
 	klog.V(1).Infof("[upgrade/apply] verifying health of cluster")
 	klog.V(1).Infof("[upgrade/apply] retrieving configuration from cluster")
-	upgradeVars, err := enforceRequirements(flags.applyPlanFlags, flags.dryRun, flags.newK8sVersionStr)
+	client, versionGetter, cfg, err := enforceRequirements(flags.applyPlanFlags, flags.dryRun, flags.newK8sVersionStr)
 	if err != nil {
 		return err
 	}
 
 	if len(flags.criSocket) != 0 {
 		fmt.Println("[upgrade/apply] Respecting the --cri-socket flag that is set with higher priority than the config file.")
-		upgradeVars.cfg.NodeRegistration.CRISocket = flags.criSocket
+		cfg.NodeRegistration.CRISocket = flags.criSocket
 	}
 
 	// Validate requested and validate actual version
 	klog.V(1).Infof("[upgrade/apply] validating requested and actual version")
-	if err := configutil.NormalizeKubernetesVersion(&upgradeVars.cfg.ClusterConfiguration); err != nil {
+	if err := configutil.NormalizeKubernetesVersion(&cfg.ClusterConfiguration); err != nil {
 		return err
 	}
 
 	// Use normalized version string in all following code.
-	flags.newK8sVersionStr = upgradeVars.cfg.KubernetesVersion
+	flags.newK8sVersionStr = cfg.KubernetesVersion
 	k8sVer, err := version.ParseSemantic(flags.newK8sVersionStr)
 	if err != nil {
 		return errors.Errorf("unable to parse normalized version %q as a semantic version", flags.newK8sVersionStr)
 	}
 	flags.newK8sVersion = k8sVer
 
-	if err := features.ValidateVersion(features.InitFeatureGates, upgradeVars.cfg.FeatureGates, upgradeVars.cfg.KubernetesVersion); err != nil {
+	if err := features.ValidateVersion(features.InitFeatureGates, cfg.FeatureGates, cfg.KubernetesVersion); err != nil {
 		return err
 	}
 
 	// Enforce the version skew policies
 	klog.V(1).Infof("[upgrade/version] enforcing version skew policies")
-	if err := EnforceVersionPolicies(flags, upgradeVars.versionGetter); err != nil {
+	if err := EnforceVersionPolicies(flags, versionGetter); err != nil {
 		return errors.Wrap(err, "[upgrade/version] FATAL")
 	}
 
@@ -194,12 +194,14 @@ func runApply(flags *applyFlags) error {
 		}
 	}
 
+	waiter := getWaiter(flags.dryRun, client)
+
 	// Use a prepuller implementation based on creating DaemonSets
 	// and block until all DaemonSets are ready; then we know for sure that all control plane images are cached locally
 	klog.V(1).Infof("[upgrade/apply] creating prepuller")
-	prepuller := upgrade.NewDaemonSetPrepuller(upgradeVars.client, upgradeVars.waiter, &upgradeVars.cfg.ClusterConfiguration)
+	prepuller := upgrade.NewDaemonSetPrepuller(client, waiter, &cfg.ClusterConfiguration)
 	componentsToPrepull := constants.MasterComponents
-	if upgradeVars.cfg.Etcd.External == nil && flags.etcdUpgrade {
+	if cfg.Etcd.External == nil && flags.etcdUpgrade {
 		componentsToPrepull = append(componentsToPrepull, constants.Etcd)
 	}
 	if err := upgrade.PrepullImagesInParallel(prepuller, flags.imagePullTimeout, componentsToPrepull); err != nil {
@@ -208,13 +210,13 @@ func runApply(flags *applyFlags) error {
 
 	// Now; perform the upgrade procedure
 	klog.V(1).Infof("[upgrade/apply] performing upgrade")
-	if err := PerformControlPlaneUpgrade(flags, upgradeVars.client, upgradeVars.waiter, upgradeVars.cfg); err != nil {
+	if err := PerformControlPlaneUpgrade(flags, client, waiter, cfg); err != nil {
 		return errors.Wrap(err, "[upgrade/apply] FATAL")
 	}
 
 	// Upgrade RBAC rules and addons.
 	klog.V(1).Infof("[upgrade/postupgrade] upgrading RBAC rules and addons")
-	if err := upgrade.PerformPostUpgradeTasks(upgradeVars.client, upgradeVars.cfg, flags.newK8sVersion, flags.dryRun); err != nil {
+	if err := upgrade.PerformPostUpgradeTasks(client, cfg, flags.newK8sVersion, flags.dryRun); err != nil {
 		return errors.Wrap(err, "[upgrade/postupgrade] FATAL post-upgrade error")
 	}
 

cmd/kubeadm/app/cmd/upgrade/common.go

@@ -42,31 +42,22 @@ import (
 	kubeconfigutil "k8s.io/kubernetes/cmd/kubeadm/app/util/kubeconfig"
 )
 
-// upgradeVariables holds variables needed for performing an upgrade or planning to do so
-// TODO - Restructure or rename upgradeVariables
-type upgradeVariables struct {
-	client        clientset.Interface
-	cfg           *kubeadmapi.InitConfiguration
-	versionGetter upgrade.VersionGetter
-	waiter        apiclient.Waiter
-}
-
 // enforceRequirements verifies that it's okay to upgrade and then returns the variables needed for the rest of the procedure
-func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion string) (*upgradeVariables, error) {
+func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion string) (clientset.Interface, upgrade.VersionGetter, *kubeadmapi.InitConfiguration, error) {
 
 	client, err := getClient(flags.kubeConfigPath, dryRun)
 	if err != nil {
-		return nil, errors.Wrapf(err, "couldn't create a Kubernetes client from file %q", flags.kubeConfigPath)
+		return nil, nil, nil, errors.Wrapf(err, "couldn't create a Kubernetes client from file %q", flags.kubeConfigPath)
 	}
 
 	// Check if the cluster is self-hosted
 	if upgrade.IsControlPlaneSelfHosted(client) {
-		return nil, errors.Errorf("cannot upgrade a self-hosted control plane")
+		return nil, nil, nil, errors.Errorf("cannot upgrade a self-hosted control plane")
 	}
 
 	// Run healthchecks against the cluster
 	if err := upgrade.CheckClusterHealth(client, flags.ignorePreflightErrorsSet); err != nil {
-		return nil, errors.Wrap(err, "[upgrade/health] FATAL")
+		return nil, nil, nil, errors.Wrap(err, "[upgrade/health] FATAL")
 	}
 
 	// Fetch the configuration from a file or ConfigMap and validate it
@@ -84,7 +75,7 @@ func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion strin
 			fmt.Println("")
 			err = errors.Errorf("the ConfigMap %q in the %s namespace used for getting configuration information was not found", constants.KubeadmConfigConfigMap, metav1.NamespaceSystem)
 		}
-		return nil, errors.Wrap(err, "[upgrade/config] FATAL")
+		return nil, nil, nil, errors.Wrap(err, "[upgrade/config] FATAL")
 	}
 
 	// If a new k8s version should be set, apply the change before printing the config
@@ -96,7 +87,7 @@ func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion strin
 	if flags.featureGatesString != "" {
 		cfg.FeatureGates, err = features.NewFeatureGate(&features.InitFeatureGates, flags.featureGatesString)
 		if err != nil {
-			return nil, errors.Wrap(err, "[upgrade/config] FATAL")
+			return nil, nil, nil, errors.Wrap(err, "[upgrade/config] FATAL")
 		}
 	}
 
@@ -105,22 +96,16 @@ func enforceRequirements(flags *applyPlanFlags, dryRun bool, newK8sVersion strin
 		for _, m := range msg {
 			fmt.Printf("[upgrade/config] %s\n", m)
 		}
-		return nil, errors.New("[upgrade/config] FATAL. Unable to upgrade a cluster using deprecated feature-gate flags. Please see the release notes")
+		return nil, nil, nil, errors.New("[upgrade/config] FATAL. Unable to upgrade a cluster using deprecated feature-gate flags. Please see the release notes")
 	}
 
 	// If the user told us to print this information out; do it!
 	if flags.printConfig {
 		printConfiguration(&cfg.ClusterConfiguration, os.Stdout)
 	}
 
-	return &upgradeVariables{
-		client: client,
-		cfg:    cfg,
-		// Use a real version getter interface that queries the API server, the kubeadm client and the Kubernetes CI system for latest versions
-		versionGetter: upgrade.NewOfflineVersionGetter(upgrade.NewKubeVersionGetter(client, os.Stdout), newK8sVersion),
-		// Use the waiter conditionally based on the dryrunning variable
-		waiter: getWaiter(dryRun, client),
-	}, nil
+	// Use a real version getter interface that queries the API server, the kubeadm client and the Kubernetes CI system for latest versions
+	return client, upgrade.NewOfflineVersionGetter(upgrade.NewKubeVersionGetter(client, os.Stdout), cfg.KubernetesVersion), cfg, nil
 }
 
 // printConfiguration prints the external version of the API to yaml

cmd/kubeadm/app/cmd/upgrade/plan.go

@@ -90,7 +90,7 @@ func runPlan(flags *planFlags) error {
 	// Start with the basics, verify that the cluster is healthy, build a client and a versionGetter. Never dry-run when planning.
 	klog.V(1).Infof("[upgrade/plan] verifying health of cluster")
 	klog.V(1).Infof("[upgrade/plan] retrieving configuration from cluster")
-	upgradeVars, err := enforceRequirements(flags.applyPlanFlags, false, flags.newK8sVersionStr)
+	client, versionGetter, cfg, err := enforceRequirements(flags.applyPlanFlags, false, flags.newK8sVersionStr)
 	if err != nil {
 		return err
 	}
@@ -99,20 +99,20 @@ func runPlan(flags *planFlags) error {
 
 	// Currently this is the only method we have for distinguishing
 	// external etcd vs static pod etcd
-	isExternalEtcd := upgradeVars.cfg.Etcd.External != nil
+	isExternalEtcd := cfg.Etcd.External != nil
 	if isExternalEtcd {
 		client, err := etcdutil.New(
-			upgradeVars.cfg.Etcd.External.Endpoints,
-			upgradeVars.cfg.Etcd.External.CAFile,
-			upgradeVars.cfg.Etcd.External.CertFile,
-			upgradeVars.cfg.Etcd.External.KeyFile)
+			cfg.Etcd.External.Endpoints,
+			cfg.Etcd.External.CAFile,
+			cfg.Etcd.External.CertFile,
+			cfg.Etcd.External.KeyFile)
 		if err != nil {
 			return err
 		}
 		etcdClient = client
 	} else {
 		// Connects to local/stacked etcd existing in the cluster
-		client, err := etcdutil.NewFromCluster(upgradeVars.client, upgradeVars.cfg.CertificatesDir)
+		client, err := etcdutil.NewFromCluster(client, cfg.CertificatesDir)
 		if err != nil {
 			return err
 		}
@@ -121,7 +121,7 @@ func runPlan(flags *planFlags) error {
 
 	// Compute which upgrade possibilities there are
 	klog.V(1).Infof("[upgrade/plan] computing upgrade possibilities")
-	availUpgrades, err := upgrade.GetAvailableUpgrades(upgradeVars.versionGetter, flags.allowExperimentalUpgrades, flags.allowRCUpgrades, etcdClient, upgradeVars.cfg.DNS.Type, upgradeVars.client)
+	availUpgrades, err := upgrade.GetAvailableUpgrades(versionGetter, flags.allowExperimentalUpgrades, flags.allowRCUpgrades, etcdClient, cfg.DNS.Type, client)
 	if err != nil {
 		return errors.Wrap(err, "[upgrade/versions] FATAL")
 	}