kubeadm upgrade plan: component config state table

This change enables kubeadm upgrade plan to print a state table with
information regarding known component config API groups. Most importantly this
information includes current and preferred version for each group and an
indication if a manual user upgrade is required.

Signed-off-by: Rostislav M. Georgiev <[email protected]>

Author: rosti

cmd/kubeadm/app/apis/output/types.go

@@ -48,6 +48,26 @@ type ComponentUpgradePlan struct {
 	NewVersion     string
 }
 
+// ComponentConfigVersionState describes the current and desired version of a component config
+type ComponentConfigVersionState struct {
+	// Group points to the Kubernetes API group that covers the config
+	Group string
+
+	// CurrentVersion is the currently active component config version
+	// NOTE: This can be empty in case the config was not found on the cluster or it was unsupported
+	// kubeadm generated version
+	CurrentVersion string
+
+	// PreferredVersion is the component config version that is currently preferred by kubeadm for use.
+	// NOTE: As of today, this is the only version supported by kubeadm.
+	PreferredVersion string
+
+	// ManualUpgradeRequired indicates if users need to manually upgrade their component config versions. This happens if
+	// the CurrentVersion of the config is user supplied (or modified) and no longer supported. Users should upgrade
+	// their component configs to PreferredVersion or any other supported component config version.
+	ManualUpgradeRequired bool
+}
+
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
 
 // UpgradePlan represents information about upgrade plan for the output
@@ -56,4 +76,6 @@ type UpgradePlan struct {
 	metav1.TypeMeta
 
 	Components []ComponentUpgradePlan
+
+	ConfigVersions []ComponentConfigVersionState
 }

cmd/kubeadm/app/apis/output/v1alpha1/types.go

@@ -48,6 +48,26 @@ type ComponentUpgradePlan struct {
 	NewVersion     string `json:"newVersion"`
 }
 
+// ComponentConfigVersionState describes the current and desired version of a component config
+type ComponentConfigVersionState struct {
+	// Group points to the Kubernetes API group that covers the config
+	Group string `json:"group"`
+
+	// CurrentVersion is the currently active component config version
+	// NOTE: This can be empty in case the config was not found on the cluster or it was unsupported
+	// kubeadm generated version
+	CurrentVersion string `json:"currentVersion"`
+
+	// PreferredVersion is the component config version that is currently preferred by kubeadm for use.
+	// NOTE: As of today, this is the only version supported by kubeadm.
+	PreferredVersion string `json:"preferredVersion"`
+
+	// ManualUpgradeRequired indicates if users need to manually upgrade their component config versions. This happens if
+	// the CurrentVersion of the config is user supplied (or modified) and no longer supported. Users should upgrade
+	// their component configs to PreferredVersion or any other supported component config version.
+	ManualUpgradeRequired bool `json:"manualUpgradeRequired"`
+}
+
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
 
 // UpgradePlan represents information about upgrade plan for the output
@@ -56,4 +76,6 @@ type UpgradePlan struct {
 	metav1.TypeMeta
 
 	Components []ComponentUpgradePlan `json:"components"`
+
+	ConfigVersions []ComponentConfigVersionState `json:"configVersions"`
 }

cmd/kubeadm/app/apis/output/v1alpha1/zz_generated.conversion.go

@@ -38,6 +38,7 @@ go_library(
         "//staging/src/k8s.io/apimachinery/pkg/util/version:go_default_library",
         "//staging/src/k8s.io/client-go/discovery/fake:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/github.com/lithammer/dedent:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
         "//vendor/github.com/pmezard/go-difflib/difflib:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",

cmd/kubeadm/app/apis/output/v1alpha1/zz_generated.deepcopy.go

@@ -19,20 +19,25 @@ package upgrade
 import (
 	"fmt"
 	"io"
+	"io/ioutil"
 	"os"
 	"sort"
 	"strings"
 	"text/tabwriter"
 
+	"github.com/lithammer/dedent"
 	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 
 	"k8s.io/apimachinery/pkg/util/version"
+	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/klog/v2"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	outputapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/output"
+	"k8s.io/kubernetes/cmd/kubeadm/app/componentconfigs"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/upgrade"
+	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 )
 
 type planFlags struct {
@@ -79,6 +84,13 @@ func runPlan(flags *planFlags, args []string) error {
 		return errors.Wrap(err, "[upgrade/versions] FATAL")
 	}
 
+	// Fetch the current state of the component configs
+	klog.V(1).Infoln("[upgrade/plan] analysing component config version states")
+	configVersionStates, err := getComponentConfigVersionStates(&cfg.ClusterConfiguration, client, flags.cfgPath)
+	if err != nil {
+		return errors.WithMessage(err, "[upgrade/versions] FATAL")
+	}
+
 	// No upgrades available
 	if len(availUpgrades) == 0 {
 		klog.V(1).Infoln("[upgrade/plan] Awesome, you're up-to-date! Enjoy!")
@@ -92,8 +104,17 @@ func runPlan(flags *planFlags, args []string) error {
 			return err
 		}
 
+		// Actually, this is needed for machine readable output only.
+		// printUpgradePlan won't output the configVersionStates as it will simply print the same table several times
+		// in the human readable output if it did so
+		plan.ConfigVersions = configVersionStates
+
 		printUpgradePlan(&up, plan, unstableVersionFlag, isExternalEtcd, os.Stdout)
 	}
+
+	// Finally, print the component config state table
+	printComponentConfigVersionStates(configVersionStates, os.Stdout)
+
 	return nil
 }
 
@@ -165,6 +186,24 @@ func genUpgradePlan(up *upgrade.Upgrade, isExternalEtcd bool) (*outputapi.Upgrad
 	return &outputapi.UpgradePlan{Components: components}, unstableVersionFlag, nil
 }
 
+func getComponentConfigVersionStates(cfg *kubeadmapi.ClusterConfiguration, client clientset.Interface, cfgPath string) ([]outputapi.ComponentConfigVersionState, error) {
+	docmap := kubeadmapi.DocumentMap{}
+
+	if cfgPath != "" {
+		bytes, err := ioutil.ReadFile(cfgPath)
+		if err != nil {
+			return nil, errors.Wrapf(err, "unable to read config file %q", cfgPath)
+		}
+
+		docmap, err = kubeadmutil.SplitYAMLDocuments(bytes)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return componentconfigs.GetVersionStates(cfg, client, docmap)
+}
+
 // printUpgradePlan prints a UX-friendly overview of what versions are available to upgrade to
 func printUpgradePlan(up *upgrade.Upgrade, plan *outputapi.UpgradePlan, unstableVersionFlag string, isExternalEtcd bool, w io.Writer) {
 	// The tab writer writes to the "real" writer w
@@ -218,8 +257,7 @@ func printUpgradePlan(up *upgrade.Upgrade, plan *outputapi.UpgradePlan, unstable
 		fmt.Fprintln(w, "")
 	}
 
-	fmt.Fprintln(w, "_____________________________________________________________________")
-	fmt.Fprintln(w, "")
+	printLineSeparator(w)
 }
 
 // sortedSliceFromStringIntMap returns a slice of the keys in the map sorted alphabetically
@@ -231,3 +269,52 @@ func sortedSliceFromStringIntMap(strMap map[string]uint16) []string {
 	sort.Strings(strSlice)
 	return strSlice
 }
+
+func strOrDash(s string) string {
+	if s != "" {
+		return s
+	}
+	return "-"
+}
+
+func yesOrNo(b bool) string {
+	if b {
+		return "yes"
+	}
+	return "no"
+}
+
+func printLineSeparator(w io.Writer) {
+	fmt.Fprintln(w, "_____________________________________________________________________")
+	fmt.Fprintln(w, "")
+}
+
+func printComponentConfigVersionStates(versionStates []outputapi.ComponentConfigVersionState, w io.Writer) {
+	if len(versionStates) == 0 {
+		fmt.Fprintln(w, "No information available on component configs.")
+		return
+	}
+
+	fmt.Fprintln(w, dedent.Dedent(`
+		The table below shows the current state of component configs as understood by this version of kubeadm.
+		Configs that have a "yes" mark in the "MANUAL UPGRADE REQUIRED" column require manual config upgrade or
+		resetting to kubeadm defaults before a successful upgrade can be performed. The version to manually
+		upgrade to is denoted in the "PREFERRED VERSION" column.
+	`))
+
+	tabw := tabwriter.NewWriter(w, 10, 4, 3, ' ', 0)
+	fmt.Fprintln(tabw, "API GROUP\tCURRENT VERSION\tPREFERRED VERSION\tMANUAL UPGRADE REQUIRED")
+
+	for _, state := range versionStates {
+		fmt.Fprintf(tabw,
+			"%s\t%s\t%s\t%s\n",
+			state.Group,
+			strOrDash(state.CurrentVersion),
+			strOrDash(state.PreferredVersion),
+			yesOrNo(state.ManualUpgradeRequired),
+		)
+	}
+
+	tabw.Flush()
+	printLineSeparator(w)
+}

cmd/kubeadm/app/apis/output/zz_generated.deepcopy.go

@@ -15,6 +15,7 @@ go_library(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/v1beta2:go_default_library",
+        "//cmd/kubeadm/app/apis/output:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
         "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",
@@ -51,6 +52,7 @@ go_test(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/v1beta2:go_default_library",
+        "//cmd/kubeadm/app/apis/output:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
         "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",