feat: export images using Transfer api

Signed-off-by: Jian Zeng <anonymousknight96@gmail.com>

pkg/transfer/archive/exporter.go

@@ -20,12 +20,19 @@ import (
 	"context"
 	"io"
 
+	"github.com/containerd/typeurl/v2"
+	v1 "github.com/opencontainers/image-spec/specs-go/v1"
+
+	"github.com/containerd/containerd/api/types"
 	transfertypes "github.com/containerd/containerd/api/types/transfer"
+	"github.com/containerd/containerd/content"
+	"github.com/containerd/containerd/images"
+	"github.com/containerd/containerd/images/archive"
 	"github.com/containerd/containerd/log"
 	"github.com/containerd/containerd/pkg/streaming"
 	"github.com/containerd/containerd/pkg/transfer/plugins"
 	tstreaming "github.com/containerd/containerd/pkg/transfer/streaming"
-	"github.com/containerd/typeurl/v2"
+	"github.com/containerd/containerd/platforms"
 )
 
 func init() {
@@ -34,24 +41,65 @@ func init() {
 	plugins.Register(&transfertypes.ImageImportStream{}, &ImageImportStream{})
 }
 
-// NewImageExportStream returns a image importer via tar stream
-// TODO: Add export options
-func NewImageExportStream(stream io.WriteCloser, mediaType string) *ImageExportStream {
+type ExportOptions struct {
+	Images               []string
+	Platforms            []v1.Platform
+	AllPlatforms         bool
+	SkipDockerManifest   bool
+	SkipNonDistributable bool
+}
+
+// NewImageExportStream returns an image exporter via tar stream
+func NewImageExportStream(stream io.WriteCloser, mediaType string, opts ExportOptions) *ImageExportStream {
 	return &ImageExportStream{
 		stream:    stream,
 		mediaType: mediaType,
+
+		images:               opts.Images,
+		platforms:            opts.Platforms,
+		allPlatforms:         opts.AllPlatforms,
+		skipDockerManifest:   opts.SkipDockerManifest,
+		skipNonDistributable: opts.SkipNonDistributable,
 	}
 }
 
 type ImageExportStream struct {
 	stream    io.WriteCloser
 	mediaType string
+
+	images               []string
+	platforms            []v1.Platform
+	allPlatforms         bool
+	skipDockerManifest   bool
+	skipNonDistributable bool
 }
 
 func (iis *ImageExportStream) ExportStream(context.Context) (io.WriteCloser, string, error) {
 	return iis.stream, iis.mediaType, nil
 }
 
+func (iis *ImageExportStream) Export(ctx context.Context, is images.Store, cs content.Store) error {
+	var opts []archive.ExportOpt
+	for _, img := range iis.images {
+		opts = append(opts, archive.WithImage(is, img))
+	}
+	if len(iis.platforms) > 0 {
+		opts = append(opts, archive.WithPlatform(platforms.Ordered(iis.platforms...)))
+	} else {
+		opts = append(opts, archive.WithPlatform(platforms.DefaultStrict()))
+	}
+	if iis.allPlatforms {
+		opts = append(opts, archive.WithAllPlatforms())
+	}
+	if iis.skipDockerManifest {
+		opts = append(opts, archive.WithSkipDockerManifest())
+	}
+	if iis.skipNonDistributable {
+		opts = append(opts, archive.WithSkipNonDistributableBlobs())
+	}
+	return archive.Export(ctx, cs, iis.stream, opts...)
+}
+
 func (iis *ImageExportStream) MarshalAny(ctx context.Context, sm streaming.StreamCreator) (typeurl.Any, error) {
 	sid := tstreaming.GenerateID("export")
 	stream, err := sm.Create(ctx, sid)
@@ -67,9 +115,22 @@ func (iis *ImageExportStream) MarshalAny(ctx context.Context, sm streaming.Strea
 		iis.stream.Close()
 	}()
 
+	var specified []*types.Platform
+	for _, p := range iis.platforms {
+		specified = append(specified, &types.Platform{
+			OS:           p.OS,
+			Architecture: p.Architecture,
+			Variant:      p.Variant,
+		})
+	}
 	s := &transfertypes.ImageExportStream{
-		Stream:    sid,
-		MediaType: iis.mediaType,
+		Stream:               sid,
+		MediaType:            iis.mediaType,
+		Images:               iis.images,
+		Platforms:            specified,
+		AllPlatforms:         iis.allPlatforms,
+		SkipDockerManifest:   iis.skipDockerManifest,
+		SkipNonDistributable: iis.skipNonDistributable,
 	}
 
 	return typeurl.MarshalAny(s)
@@ -87,8 +148,22 @@ func (iis *ImageExportStream) UnmarshalAny(ctx context.Context, sm streaming.Str
 		return err
 	}
 
+	var specified []v1.Platform
+	for _, p := range s.Platforms {
+		specified = append(specified, v1.Platform{
+			OS:           p.OS,
+			Architecture: p.Architecture,
+			Variant:      p.Variant,
+		})
+	}
+
 	iis.stream = tstreaming.WriteByteStream(ctx, stream)
 	iis.mediaType = s.MediaType
+	iis.images = s.Images
+	iis.platforms = specified
+	iis.allPlatforms = s.AllPlatforms
+	iis.skipDockerManifest = s.SkipDockerManifest
+	iis.skipNonDistributable = s.SkipNonDistributable
 
 	return nil
 }