containerd nginx in golang

container.go

package main

import (
	"context"
	"fmt"
	"log"
	"syscall"
	"time"

	// "github.com/containerd/cgroups/v3"
	// "github.com/containerd/cgroups/v3/cgroup1"
	cgroupsv2 "github.com/containerd/cgroups/v3/cgroup2"

	"github.com/containerd/containerd"
	"github.com/containerd/containerd/cio"
	"github.com/containerd/containerd/namespaces"
	"github.com/containerd/containerd/oci"
	"github.com/opencontainers/runtime-spec/specs-go"
	//sandboxstore "github.com/containerd/cri/pkg/store/sandbox"
	//"github.com/containerd/typeurl"
	//specs "github.com/opencontainers/runtime-spec/specs-go"
)

func init() {
	// typeurl.Register(&sandboxstore.Metadata{},
	// 	"github.com/containerd/cri/pkg/store/sandbox", "Metadata")
}

func main() {
	if err := nginxExample(); err != nil {
		log.Fatal(err)
	}
}

func nginxExample() error {

	client, err := containerd.New("/run/containerd/containerd.sock")
	if err != nil {
		return err
	}
	defer client.Close()

	ctx := namespaces.WithNamespace(context.Background(), "example")

	image, err := client.Pull(ctx, "docker.io/library/nginx:latest", containerd.WithPullUnpack)
	if err != nil {
		return err
	}

	//client.Containers()

	containerId := "mynginx-1"
	hostname := "srashid2"
	container, err := client.NewContainer(
		ctx,
		containerId,
		containerd.WithImage(image),
		containerd.WithNewSnapshot("nginx-1", image),
		containerd.WithNewSpec(
			oci.WithImageConfig(image),
			oci.WithHostHostsFile,
			oci.WithHostResolvconf,
			oci.WithHostNamespace(specs.NetworkNamespace),
			oci.WithEnv([]string{fmt.Sprintf("HOSTNAME=%s", hostname)}),
			//oci.WithImageConfigArgs(image, launchSpec.Cmd),
		),
	)
	if err != nil {
		return err
	}
	defer container.Delete(ctx, containerd.WithSnapshotCleanup)

	fmt.Println("NewTask")
	task, err := container.NewTask(ctx, cio.NewCreator(cio.WithStdio))
	if err != nil {
		fmt.Printf("NewTask error %v", err)
		return err
	}
	defer task.Delete(ctx)

	fmt.Println("Waiting")
	exitStatusC, err := task.Wait(ctx)
	if err != nil {
		fmt.Printf("Wait error %v", err)
		fmt.Println(err)
	}

	if err := task.Start(ctx); err != nil {
		fmt.Printf("Start error %v", err)
		return err
	}

	groupPath, err := cgroupsv2.PidGroupPath(int(task.Pid()))
	if err != nil {
		fmt.Printf("Start error %v", err)
		return err
	}
	cgroup2, err := cgroupsv2.Load(groupPath)
	if err != nil {
		fmt.Printf("Start error %v", err)
		return err
	}
	stat, err := cgroup2.Stat()
	if err != nil {
		fmt.Printf("Start error %v", err)
		return err
	}

	fmt.Printf("Stat %s\n", stat.CPU)
	time.Sleep(5 * time.Second)

	if err := task.Kill(ctx, syscall.SIGTERM); err != nil {
		return err
	}

	status := <-exitStatusC
	code, _, err := status.Result()
	if err != nil {
		return err
	}
	fmt.Printf("nginx exited with status: %d\n", code)

	return nil
}