Add initial container implementation.

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/server/container_create.go

@@ -17,14 +17,84 @@ limitations under the License.
 package server
 
 import (
-	"errors"
+	"fmt"
+	"time"
 
+	"github.com/golang/glog"
 	"golang.org/x/net/context"
 
 	"k8s.io/kubernetes/pkg/kubelet/api/v1alpha1/runtime"
+
+	"github.com/kubernetes-incubator/cri-containerd/pkg/metadata"
 )
 
 // CreateContainer creates a new container in the given PodSandbox.
-func (c *criContainerdService) CreateContainer(ctx context.Context, r *runtime.CreateContainerRequest) (*runtime.CreateContainerResponse, error) {
-	return nil, errors.New("not implemented")
+func (c *criContainerdService) CreateContainer(ctx context.Context, r *runtime.CreateContainerRequest) (retRes *runtime.CreateContainerResponse, retErr error) {
+	glog.V(2).Infof("CreateContainer within sandbox %q with container config %+v and sandbox config %+v",
+		r.GetPodSandboxId(), r.GetConfig(), r.GetSandboxConfig())
+	defer func() {
+		if retErr == nil {
+			glog.V(2).Infof("CreateContainer returns container id %q", retRes.GetContainerId())
+		}
+	}()
+
+	config := r.GetConfig()
+	sandboxConfig := r.GetSandboxConfig()
+	sandbox, err := c.getSandbox(r.GetPodSandboxId())
+	if err != nil {
+		return nil, fmt.Errorf("failed to find sandbox id %q: %v", r.GetPodSandboxId(), err)
+	}
+
+	// Generate unique id and name for the container and reserve the name.
+	// Reserve the container name to avoid concurrent `CreateContainer` request creating
+	// the same container.
+	id := generateID()
+	name := makeContainerName(config.GetMetadata(), sandboxConfig.GetMetadata())
+	if err := c.containerNameIndex.Reserve(name, id); err != nil {
+		return nil, fmt.Errorf("failed to reserve container name %q: %v", name, err)
+	}
+	defer func() {
+		// Release the name if the function returns with an error.
+		if retErr != nil {
+			c.containerNameIndex.ReleaseByName(name)
+		}
+	}()
+
+	// Create initial container metadata.
+	meta := metadata.ContainerMetadata{
+		ID:        id,
+		Name:      name,
+		SandboxID: sandbox.ID,
+		Config:    config,
+	}
+
+	// TODO(random-liu): [P0] Prepare container rootfs.
+
+	// TODO(random-liu): [P0] Set ImageRef in ContainerMetadata with image id.
+
+	// Create container root directory.
+	containerRootDir := getContainerRootDir(c.rootDir, id)
+	if err := c.os.MkdirAll(containerRootDir, 0755); err != nil {
+		return nil, fmt.Errorf("failed to create container root directory %q: %v",
+			containerRootDir, err)
+	}
+	defer func() {
+		if retErr != nil {
+			// Cleanup the container root directory.
+			if err := c.os.RemoveAll(containerRootDir); err != nil {
+				glog.Errorf("Failed to remove container root directory %q: %v",
+					containerRootDir, err)
+			}
+		}
+	}()
+
+	// Update container CreatedAt.
+	meta.CreatedAt = time.Now().UnixNano()
+	// Add container into container store.
+	if err := c.containerStore.Create(meta); err != nil {
+		return nil, fmt.Errorf("failed to add container metadata %+v into store: %v",
+			meta, err)
+	}
+
+	return &runtime.CreateContainerResponse{ContainerId: id}, nil
 }