check image readiness during restart

fix #303
Signed-off-by: yanxuean <yan.xuean@zte.com.cn>

pkg/server/restart.go

@@ -33,6 +33,8 @@ import (
 	"golang.org/x/net/context"
 	"k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime"
 
+	imagemanage "github.com/containerd/containerd/images"
+	"github.com/containerd/containerd/platforms"
 	cio "github.com/kubernetes-incubator/cri-containerd/pkg/server/io"
 	containerstore "github.com/kubernetes-incubator/cri-containerd/pkg/store/container"
 	imagestore "github.com/kubernetes-incubator/cri-containerd/pkg/store/image"
@@ -101,6 +103,11 @@ func (c *criContainerdService) recover(ctx context.Context) error {
 		return fmt.Errorf("failed to load images: %v", err)
 	}
 	for _, image := range images {
+		if _, err := c.client.SnapshotService(c.config.ContainerdConfig.Snapshotter).Stat(ctx, image.ChainID); err != nil {
+			glog.Warningf("Failed to check top snapshot %+v: %v", image, err)
+			continue
+		}
+
 		glog.V(4).Infof("Loaded image %+v", image)
 		if err := c.imageStore.Add(image); err != nil {
 			return fmt.Errorf("failed to add image %q to store: %v", image.ID, err)
@@ -342,6 +349,10 @@ func loadImages(ctx context.Context, cImages []containerd.Image, provider conten
 		// imgs len must be > 0, or else the entry will not be created in
 		// previous loop.
 		i := imgs[0]
+		if ok, _, _, _, err := imagemanage.Check(ctx, provider, i.Target(), platforms.Default()); !ok || err != nil {
+			glog.Warningf("Failed to check image readiness for %q: %v", i.Name(), err)
+			continue
+		}
 		info, err := getImageInfo(ctx, i, provider)
 		if err != nil {
 			glog.Warningf("Failed to get image info for %q: %v", i.Name(), err)