vendor: revendor metrics-server, custom-metrics-apiserver

vendor/k8s.io/apiserver/pkg/server/healthz/healthz.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"fmt"
 	"net/http"
+	"reflect"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -29,7 +30,7 @@ import (
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/endpoints/metrics"
 	"k8s.io/apiserver/pkg/server/httplog"
-	"k8s.io/klog"
+	"k8s.io/klog/v2"
 )
 
 // HealthChecker is a named healthz checker.
@@ -81,6 +82,43 @@ func (l *log) Check(_ *http.Request) error {
 	return fmt.Errorf("logging blocked")
 }
 
+type cacheSyncWaiter interface {
+	WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool
+}
+
+type informerSync struct {
+	cacheSyncWaiter cacheSyncWaiter
+}
+
+var _ HealthChecker = &informerSync{}
+
+// NewInformerSyncHealthz returns a new HealthChecker that will pass only if all informers in the given cacheSyncWaiter sync.
+func NewInformerSyncHealthz(cacheSyncWaiter cacheSyncWaiter) HealthChecker {
+	return &informerSync{
+		cacheSyncWaiter: cacheSyncWaiter,
+	}
+}
+
+func (i *informerSync) Name() string {
+	return "informer-sync"
+}
+
+func (i *informerSync) Check(_ *http.Request) error {
+	stopCh := make(chan struct{})
+	// Close stopCh to force checking if informers are synced now.
+	close(stopCh)
+
+	informersByStarted := make(map[bool][]string)
+	for informerType, started := range i.cacheSyncWaiter.WaitForCacheSync(stopCh) {
+		informersByStarted[started] = append(informersByStarted[started], informerType.String())
+	}
+
+	if notStarted := informersByStarted[false]; len(notStarted) > 0 {
+		return fmt.Errorf("%d informers not started yet: %v", len(notStarted), notStarted)
+	}
+	return nil
+}
+
 // NamedCheck returns a healthz checker for the given name and function.
 func NamedCheck(name string, check func(r *http.Request) error) HealthChecker {
 	return &healthzCheck{name, check}
@@ -131,6 +169,8 @@ func InstallPathHandler(mux mux, path string, checks ...HealthChecker) {
 			/* subresource = */ path,
 			/* scope = */ "",
 			/* component = */ "",
+			/* deprecated */ false,
+			/* removedRelease */ "",
 			handleRootHealthz(checks...)))
 	for _, check := range checks {
 		mux.Handle(fmt.Sprintf("%s/%v", path, check.Name()), adaptCheckToHandler(check.Check))
@@ -170,35 +210,38 @@ func getExcludedChecks(r *http.Request) sets.String {
 // handleRootHealthz returns an http.HandlerFunc that serves the provided checks.
 func handleRootHealthz(checks ...HealthChecker) http.HandlerFunc {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		failed := false
 		excluded := getExcludedChecks(r)
-		var verboseOut bytes.Buffer
+		// failedVerboseLogOutput is for output to the log.  It indicates detailed failed output information for the log.
+		var failedVerboseLogOutput bytes.Buffer
+		var failedChecks []string
+		var individualCheckOutput bytes.Buffer
 		for _, check := range checks {
 			// no-op the check if we've specified we want to exclude the check
 			if excluded.Has(check.Name()) {
 				excluded.Delete(check.Name())
-				fmt.Fprintf(&verboseOut, "[+]%v excluded: ok\n", check.Name())
+				fmt.Fprintf(&individualCheckOutput, "[+]%s excluded: ok\n", check.Name())
 				continue
 			}
 			if err := check.Check(r); err != nil {
 				// don't include the error since this endpoint is public.  If someone wants more detail
 				// they should have explicit permission to the detailed checks.
-				klog.V(4).Infof("healthz check %v failed: %v", check.Name(), err)
-				fmt.Fprintf(&verboseOut, "[-]%v failed: reason withheld\n", check.Name())
-				failed = true
+				fmt.Fprintf(&individualCheckOutput, "[-]%s failed: reason withheld\n", check.Name())
+				// but we do want detailed information for our log
+				fmt.Fprintf(&failedVerboseLogOutput, "[-]%s failed: %v\n", check.Name(), err)
+				failedChecks = append(failedChecks, check.Name())
 			} else {
-				fmt.Fprintf(&verboseOut, "[+]%v ok\n", check.Name())
+				fmt.Fprintf(&individualCheckOutput, "[+]%s ok\n", check.Name())
 			}
 		}
 		if excluded.Len() > 0 {
-			fmt.Fprintf(&verboseOut, "warn: some health checks cannot be excluded: no matches for %v\n", formatQuoted(excluded.List()...))
-			klog.Warningf("cannot exclude some health checks, no health checks are installed matching %v",
+			fmt.Fprintf(&individualCheckOutput, "warn: some health checks cannot be excluded: no matches for %s\n", formatQuoted(excluded.List()...))
+			klog.Warningf("cannot exclude some health checks, no health checks are installed matching %s",
 				formatQuoted(excluded.List()...))
 		}
 		// always be verbose on failure
-		if failed {
-			klog.V(2).Infof("%vhealthz check failed", verboseOut.String())
-			http.Error(httplog.Unlogged(r, w), fmt.Sprintf("%vhealthz check failed", verboseOut.String()), http.StatusInternalServerError)
+		if len(failedChecks) > 0 {
+			klog.V(2).Infof("healthz check failed: %s\n%v", strings.Join(failedChecks, ","), failedVerboseLogOutput.String())
+			http.Error(httplog.Unlogged(r, w), fmt.Sprintf("%shealthz check failed", individualCheckOutput.String()), http.StatusInternalServerError)
 			return
 		}
 
@@ -209,7 +252,7 @@ func handleRootHealthz(checks ...HealthChecker) http.HandlerFunc {
 			return
 		}
 
-		verboseOut.WriteTo(w)
+		individualCheckOutput.WriteTo(w)
 		fmt.Fprint(w, "healthz check passed\n")
 	})
 }