Wait for kine to be ready during startup

So k0s will not continue with its startup sequence, and will exit with
an error message indicating that kine was not okay.

Signed-off-by: Tom Wieczorek <[email protected]>

pkg/component/controller/kine.go

@@ -25,20 +25,21 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/k0sproject/k0s/internal/pkg/dir"
+	"github.com/k0sproject/k0s/internal/pkg/users"
 	"github.com/k0sproject/k0s/pkg/apis/k0s/v1beta1"
+	"github.com/k0sproject/k0s/pkg/assets"
 	"github.com/k0sproject/k0s/pkg/component/manager"
 	"github.com/k0sproject/k0s/pkg/config"
 	"github.com/k0sproject/k0s/pkg/config/kine"
+	"github.com/k0sproject/k0s/pkg/constant"
 	"github.com/k0sproject/k0s/pkg/etcd"
-	clientv3 "go.etcd.io/etcd/client/v3"
+	"github.com/k0sproject/k0s/pkg/supervisor"
 
-	"github.com/sirupsen/logrus"
+	"k8s.io/apimachinery/pkg/util/wait"
 
-	"github.com/k0sproject/k0s/internal/pkg/dir"
-	"github.com/k0sproject/k0s/internal/pkg/users"
-	"github.com/k0sproject/k0s/pkg/assets"
-	"github.com/k0sproject/k0s/pkg/constant"
-	"github.com/k0sproject/k0s/pkg/supervisor"
+	"github.com/sirupsen/logrus"
+	clientv3 "go.etcd.io/etcd/client/v3"
 )
 
 // Kine implement the component interface to run kine
@@ -131,7 +132,26 @@ func (k *Kine) Start(ctx context.Context) error {
 		GID: k.gid,
 	}
 
-	return k.supervisor.Supervise()
+	if err := k.supervisor.Supervise(); err != nil {
+		return err
+	}
+
+	var err error
+	waitErr := wait.PollUntilContextTimeout(ctx, 350*time.Millisecond, 2*time.Minute, true, func(ctx context.Context) (bool, error) {
+		ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
+		defer cancel()
+		err = k.ready(ctx)
+		return err == nil, nil
+	})
+
+	if waitErr != nil {
+		if err != nil {
+			return fmt.Errorf("%w (%w)", waitErr, err)
+		}
+		return waitErr
+	}
+
+	return nil
 }
 
 // Stop stops kine
@@ -144,15 +164,18 @@ const hcKey = "/k0s-health-check"
 const hcValue = "value"
 
 func (k *Kine) Ready() error {
-	ctx, cancel := context.WithTimeout(context.TODO(), 1*time.Second)
-	defer cancel()
+	return k.ready(context.TODO())
+}
 
+func (k *Kine) ready(ctx context.Context) error {
+	ctx, cancel := context.WithTimeout(ctx, 1*time.Second)
+	defer cancel()
 	ok, err := k.bypassClient.Write(ctx, hcKey, hcValue, 64*time.Second)
 	if err != nil {
 		return fmt.Errorf("kine-etcd-health: %w", err)
 	}
 	if !ok {
-		logrus.Warningf("kine-etcd-health: health-check value was not written")
+		return errors.New("kine-etcd-health: health-check value was not written")
 	}
 
 	v, err := k.bypassClient.Read(ctx, hcKey)