kubeadm: pass io.Writer and "patches dir" to WriteConfigToDisk()

With phases/kubelet/WriteConfigToDisk() about to support patches
it is required that the function accepts an io.Writer
where the PatchManager can output to and also a patch directory.

Modify all call sites of the function WriteConfigToDisk()
to properly prepare an pass an io.Writer and patches dir to it.
This results in command phases for init/join/upgrade to pass
the root io.Writer (usually stdout) and the patchesDir populated
either via the config file or --patches flag.

cmd/kubeadm/app/cmd/phases/init/kubelet.go

@@ -74,7 +74,7 @@ func runKubeletStart(c workflow.RunData) error {
 	}
 
 	// Write the kubelet configuration file to disk.
-	if err := kubeletphase.WriteConfigToDisk(&data.Cfg().ClusterConfiguration, data.KubeletDir()); err != nil {
+	if err := kubeletphase.WriteConfigToDisk(&data.Cfg().ClusterConfiguration, data.KubeletDir(), data.PatchesDir(), data.OutputWriter()); err != nil {
 		return errors.Wrap(err, "error writing kubelet configuration to disk")
 	}
 

cmd/kubeadm/app/cmd/phases/join/kubelet.go

@@ -174,7 +174,7 @@ func runKubeletStartJoinPhase(c workflow.RunData) (returnErr error) {
 	}
 
 	// Write the configuration for the kubelet (using the bootstrap token credentials) to disk so the kubelet can start
-	if err := kubeletphase.WriteConfigToDisk(&initCfg.ClusterConfiguration, data.KubeletDir()); err != nil {
+	if err := kubeletphase.WriteConfigToDisk(&initCfg.ClusterConfiguration, data.KubeletDir(), data.PatchesDir(), data.OutputWriter()); err != nil {
 		return err
 	}
 

cmd/kubeadm/app/cmd/phases/upgrade/node/data.go

@@ -17,6 +17,8 @@ limitations under the License.
 package node
 
 import (
+	"io"
+
 	"k8s.io/apimachinery/pkg/util/sets"
 	clientset "k8s.io/client-go/kubernetes"
 
@@ -35,4 +37,5 @@ type Data interface {
 	IgnorePreflightErrors() sets.String
 	PatchesDir() string
 	KubeConfigPath() string
+	OutputWriter() io.Writer
 }

cmd/kubeadm/app/cmd/phases/upgrade/node/kubeletconfig.go

@@ -73,7 +73,7 @@ func runKubeletConfigPhase() func(c workflow.RunData) error {
 		// TODO: Checkpoint the current configuration first so that if something goes wrong it can be recovered
 
 		// Store the kubelet component configuration.
-		if err = kubeletphase.WriteConfigToDisk(&cfg.ClusterConfiguration, kubeletDir); err != nil {
+		if err = kubeletphase.WriteConfigToDisk(&cfg.ClusterConfiguration, kubeletDir, data.PatchesDir(), data.OutputWriter()); err != nil {
 			return err
 		}
 

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

@@ -168,7 +168,7 @@ func runApply(flags *applyFlags, args []string) error {
 
 	// Upgrade RBAC rules and addons.
 	klog.V(1).Infoln("[upgrade/postupgrade] upgrading RBAC rules and addons")
-	if err := upgrade.PerformPostUpgradeTasks(client, cfg, flags.dryRun); err != nil {
+	if err := upgrade.PerformPostUpgradeTasks(client, cfg, flags.patchesDir, flags.dryRun, flags.applyPlanFlags.out); err != nil {
 		return errors.Wrap(err, "[upgrade/postupgrade] FATAL post-upgrade error")
 	}
 

cmd/kubeadm/app/cmd/upgrade/node.go

@@ -17,6 +17,7 @@ limitations under the License.
 package upgrade
 
 import (
+	"io"
 	"os"
 
 	"github.com/pkg/errors"
@@ -63,10 +64,11 @@ type nodeData struct {
 	patchesDir            string
 	ignorePreflightErrors sets.String
 	kubeConfigPath        string
+	outputWriter          io.Writer
 }
 
 // newCmdNode returns the cobra command for `kubeadm upgrade node`
-func newCmdNode() *cobra.Command {
+func newCmdNode(out io.Writer) *cobra.Command {
 	nodeOptions := newNodeOptions()
 	nodeRunner := workflow.NewRunner()
 
@@ -92,7 +94,7 @@ func newCmdNode() *cobra.Command {
 	// sets the data builder function, that will be used by the runner
 	// both when running the entire workflow or single phases
 	nodeRunner.SetDataInitializer(func(cmd *cobra.Command, args []string) (workflow.RunData, error) {
-		return newNodeData(cmd, args, nodeOptions)
+		return newNodeData(cmd, args, nodeOptions, out)
 	})
 
 	// binds the Runner to kubeadm upgrade node command by altering
@@ -123,7 +125,7 @@ func addUpgradeNodeFlags(flagSet *flag.FlagSet, nodeOptions *nodeOptions) {
 // newNodeData returns a new nodeData struct to be used for the execution of the kubeadm upgrade node workflow.
 // This func takes care of validating nodeOptions passed to the command, and then it converts
 // options into the internal InitConfiguration type that is used as input all the phases in the kubeadm upgrade node workflow
-func newNodeData(cmd *cobra.Command, args []string, options *nodeOptions) (*nodeData, error) {
+func newNodeData(cmd *cobra.Command, args []string, options *nodeOptions, out io.Writer) (*nodeData, error) {
 	client, err := getClient(options.kubeConfigPath, options.dryRun)
 	if err != nil {
 		return nil, errors.Wrapf(err, "couldn't create a Kubernetes client from file %q", options.kubeConfigPath)
@@ -168,6 +170,7 @@ func newNodeData(cmd *cobra.Command, args []string, options *nodeOptions) (*node
 		patchesDir:            options.patchesDir,
 		ignorePreflightErrors: ignorePreflightErrorsSet,
 		kubeConfigPath:        options.kubeConfigPath,
+		outputWriter:          out,
 	}, nil
 }
 
@@ -215,3 +218,7 @@ func (d *nodeData) IgnorePreflightErrors() sets.String {
 func (d *nodeData) KubeConfigPath() string {
 	return d.kubeConfigPath
 }
+
+func (d *nodeData) OutputWriter() io.Writer {
+	return d.outputWriter
+}

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

@@ -60,7 +60,7 @@ func NewCmdUpgrade(out io.Writer) *cobra.Command {
 	cmd.AddCommand(newCmdApply(flags))
 	cmd.AddCommand(newCmdPlan(flags))
 	cmd.AddCommand(newCmdDiff(out))
-	cmd.AddCommand(newCmdNode())
+	cmd.AddCommand(newCmdNode(out))
 	return cmd
 }
 

cmd/kubeadm/app/phases/kubelet/config.go

@@ -18,6 +18,7 @@ package kubelet
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 
@@ -38,7 +39,7 @@ import (
 
 // WriteConfigToDisk writes the kubelet config object down to a file
 // Used at "kubeadm init" and "kubeadm upgrade" time
-func WriteConfigToDisk(cfg *kubeadmapi.ClusterConfiguration, kubeletDir string) error {
+func WriteConfigToDisk(cfg *kubeadmapi.ClusterConfiguration, kubeletDir, patchesDir string, output io.Writer) error {
 	kubeletCfg, ok := cfg.ComponentConfigs[componentconfigs.KubeletGroup]
 	if !ok {
 		return errors.New("no kubelet component config found")

cmd/kubeadm/app/phases/upgrade/postupgrade.go

@@ -19,6 +19,7 @@ package upgrade
 import (
 	"context"
 	"fmt"
+	"io"
 	"os"
 	"strings"
 
@@ -48,7 +49,7 @@ import (
 
 // PerformPostUpgradeTasks runs nearly the same functions as 'kubeadm init' would do
 // Note that the mark-control-plane phase is left out, not needed, and no token is created as that doesn't belong to the upgrade
-func PerformPostUpgradeTasks(client clientset.Interface, cfg *kubeadmapi.InitConfiguration, dryRun bool) error {
+func PerformPostUpgradeTasks(client clientset.Interface, cfg *kubeadmapi.InitConfiguration, patchesDir string, dryRun bool, out io.Writer) error {
 	errs := []error{}
 
 	// Upload currently used configuration to the cluster
@@ -64,7 +65,7 @@ func PerformPostUpgradeTasks(client clientset.Interface, cfg *kubeadmapi.InitCon
 	}
 
 	// Write the new kubelet config down to disk and the env file if needed
-	if err := writeKubeletConfigFiles(client, cfg, dryRun); err != nil {
+	if err := writeKubeletConfigFiles(client, cfg, patchesDir, dryRun, out); err != nil {
 		errs = append(errs, err)
 	}
 
@@ -158,7 +159,7 @@ func PerformPostUpgradeTasks(client clientset.Interface, cfg *kubeadmapi.InitCon
 	return errorsutil.NewAggregate(errs)
 }
 
-func writeKubeletConfigFiles(client clientset.Interface, cfg *kubeadmapi.InitConfiguration, dryRun bool) error {
+func writeKubeletConfigFiles(client clientset.Interface, cfg *kubeadmapi.InitConfiguration, patchesDir string, dryRun bool, out io.Writer) error {
 	kubeletDir, err := GetKubeletDir(dryRun)
 	if err != nil {
 		// The error here should never occur in reality, would only be thrown if /tmp doesn't exist on the machine.
@@ -166,7 +167,7 @@ func writeKubeletConfigFiles(client clientset.Interface, cfg *kubeadmapi.InitCon
 	}
 	errs := []error{}
 	// Write the configuration for the kubelet down to disk so the upgraded kubelet can start with fresh config
-	if err := kubeletphase.WriteConfigToDisk(&cfg.ClusterConfiguration, kubeletDir); err != nil {
+	if err := kubeletphase.WriteConfigToDisk(&cfg.ClusterConfiguration, kubeletDir, patchesDir, out); err != nil {
 		errs = append(errs, errors.Wrap(err, "error writing kubelet configuration to file"))
 	}