Merge pull request #1880 from AkihiroSuda/refactor-importer

importer: refactor and fix GC

cmd/ctr/commands/images/export.go

@@ -5,6 +5,7 @@ import (
 	"os"
 
 	"github.com/containerd/containerd/cmd/ctr/commands"
+	oci "github.com/containerd/containerd/images/oci"
 	"github.com/containerd/containerd/reference"
 	digest "github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
@@ -13,11 +14,14 @@ import (
 )
 
 var exportCommand = cli.Command{
-	Name:        "export",
-	Usage:       "export an image",
-	ArgsUsage:   "[flags] <out> <image>",
-	Description: "export an image to a tar stream",
+	Name:      "export",
+	Usage:     "export an image",
+	ArgsUsage: "[flags] <out> <image>",
+	Description: `Export an image to a tar stream.
+Currently, only OCI format is supported.
+`,
 	Flags: []cli.Flag{
+		// TODO(AkihiroSuda): make this map[string]string as in moby/moby#33355?
 		cli.StringFlag{
 			Name:  "oci-ref-name",
 			Value: "",
@@ -78,7 +82,7 @@ var exportCommand = cli.Command{
 				return nil
 			}
 		}
-		r, err := client.Export(ctx, desc)
+		r, err := client.Export(ctx, &oci.V1Exporter{}, desc)
 		if err != nil {
 			return err
 		}

cmd/ctr/commands/images/import.go

@@ -5,37 +5,66 @@ import (
 	"io"
 	"os"
 
-	"github.com/containerd/containerd"
 	"github.com/containerd/containerd/cmd/ctr/commands"
+	"github.com/containerd/containerd/images"
+	oci "github.com/containerd/containerd/images/oci"
 	"github.com/containerd/containerd/log"
 	"github.com/urfave/cli"
 )
 
 var importCommand = cli.Command{
-	Name:        "import",
-	Usage:       "import an image",
-	ArgsUsage:   "[flags] <ref> <in>",
-	Description: "import an image from a tar stream",
-	Flags: []cli.Flag{
+	Name:      "import",
+	Usage:     "import images",
+	ArgsUsage: "[flags] <in>",
+	Description: `Import images from a tar stream.
+Implemented formats:
+- oci.v1     (default)
+
+
+For oci.v1 format, you need to specify --oci-name because an OCI archive contains image refs (tags)
+but does not contain the base image name.
+
+e.g.
+  $ ctr images import --format oci.v1 --oci-name foo/bar foobar.tar
+
+If foobar.tar contains an OCI ref named "latest" and anonymous ref "sha256:deadbeef", the command will create
+"foo/bar:latest" and "foo/bar@sha256:deadbeef" images in the containerd store.
+`,
+	Flags: append([]cli.Flag{
 		cli.StringFlag{
-			Name:  "ref-object",
-			Value: "",
-			Usage: "reference object e.g. tag@digest (default: use the object specified in ref)",
+			Name:  "format",
+			Value: "oci.v1",
+			Usage: "image format. See DESCRIPTION.",
 		},
-		commands.LabelFlag,
-	},
+		cli.StringFlag{
+			Name:  "oci-name",
+			Value: "unknown/unknown",
+			Usage: "prefix added to either oci.v1 ref annotation or digest",
+		},
+		// TODO(AkihiroSuda): support commands.LabelFlag (for all children objects)
+	}, commands.SnapshotterFlags...),
+
 	Action: func(context *cli.Context) error {
 		var (
-			ref       = context.Args().First()
-			in        = context.Args().Get(1)
-			refObject = context.String("ref-object")
-			labels    = commands.LabelArgs(context.StringSlice("label"))
+			in            = context.Args().First()
+			imageImporter images.Importer
 		)
+
+		switch format := context.String("format"); format {
+		case "oci.v1":
+			imageImporter = &oci.V1Importer{
+				ImageName: context.String("oci-name"),
+			}
+		default:
+			return fmt.Errorf("unknown format %s", format)
+		}
+
 		client, ctx, cancel, err := commands.NewClient(context)
 		if err != nil {
 			return err
 		}
 		defer cancel()
+
 		var r io.ReadCloser
 		if in == "-" {
 			r = os.Stdin
@@ -45,12 +74,7 @@ var importCommand = cli.Command{
 				return err
 			}
 		}
-		img, err := client.Import(ctx,
-			ref,
-			r,
-			containerd.WithRefObject(refObject),
-			containerd.WithImportLabels(labels),
-		)
+		imgs, err := client.Import(ctx, imageImporter, r)
 		if err != nil {
 			return err
 		}
@@ -58,12 +82,17 @@ var importCommand = cli.Command{
 			return err
 		}
 
-		log.G(ctx).WithField("image", ref).Debug("unpacking")
+		log.G(ctx).Debugf("unpacking %d images", len(imgs))
 
-		// TODO: Show unpack status
-		fmt.Printf("unpacking %s...", img.Target().Digest)
-		err = img.Unpack(ctx, context.String("snapshotter"))
-		fmt.Println("done")
-		return err
+		for _, img := range imgs {
+			// TODO: Show unpack status
+			fmt.Printf("unpacking %s (%s)...", img.Name(), img.Target().Digest)
+			err = img.Unpack(ctx, context.String("snapshotter"))
+			if err != nil {
+				return err
+			}
+			fmt.Println("done")
+		}
+		return nil
 	},
 }