Move import/export code to separate client file

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

client.go

@@ -19,7 +19,6 @@ package containerd
 import (
 	"context"
 	"fmt"
-	"io"
 	"net/http"
 	"runtime"
 	"strconv"
@@ -551,98 +550,3 @@ func (c *Client) Version(ctx context.Context) (Version, error) {
 		Revision: response.Revision,
 	}, nil
 }
-
-type importOpts struct {
-}
-
-// ImportOpt allows the caller to specify import specific options
-type ImportOpt func(c *importOpts) error
-
-func resolveImportOpt(opts ...ImportOpt) (importOpts, error) {
-	var iopts importOpts
-	for _, o := range opts {
-		if err := o(&iopts); err != nil {
-			return iopts, err
-		}
-	}
-	return iopts, nil
-}
-
-// Import imports an image from a Tar stream using reader.
-// Caller needs to specify importer. Future version may use oci.v1 as the default.
-// Note that unreferrenced blobs may be imported to the content store as well.
-func (c *Client) Import(ctx context.Context, importer images.Importer, reader io.Reader, opts ...ImportOpt) ([]Image, error) {
-	_, err := resolveImportOpt(opts...) // unused now
-	if err != nil {
-		return nil, err
-	}
-
-	ctx, done, err := c.WithLease(ctx)
-	if err != nil {
-		return nil, err
-	}
-	defer done(ctx)
-
-	imgrecs, err := importer.Import(ctx, c.ContentStore(), reader)
-	if err != nil {
-		// is.Update() is not called on error
-		return nil, err
-	}
-
-	is := c.ImageService()
-	var images []Image
-	for _, imgrec := range imgrecs {
-		if updated, err := is.Update(ctx, imgrec, "target"); err != nil {
-			if !errdefs.IsNotFound(err) {
-				return nil, err
-			}
-
-			created, err := is.Create(ctx, imgrec)
-			if err != nil {
-				return nil, err
-			}
-
-			imgrec = created
-		} else {
-			imgrec = updated
-		}
-
-		images = append(images, &image{
-			client: c,
-			i:      imgrec,
-		})
-	}
-	return images, nil
-}
-
-type exportOpts struct {
-}
-
-// ExportOpt allows the caller to specify export-specific options
-type ExportOpt func(c *exportOpts) error
-
-func resolveExportOpt(opts ...ExportOpt) (exportOpts, error) {
-	var eopts exportOpts
-	for _, o := range opts {
-		if err := o(&eopts); err != nil {
-			return eopts, err
-		}
-	}
-	return eopts, nil
-}
-
-// Export exports an image to a Tar stream.
-// OCI format is used by default.
-// It is up to caller to put "org.opencontainers.image.ref.name" annotation to desc.
-// TODO(AkihiroSuda): support exporting multiple descriptors at once to a single archive stream.
-func (c *Client) Export(ctx context.Context, exporter images.Exporter, desc ocispec.Descriptor, opts ...ExportOpt) (io.ReadCloser, error) {
-	_, err := resolveExportOpt(opts...) // unused now
-	if err != nil {
-		return nil, err
-	}
-	pr, pw := io.Pipe()
-	go func() {
-		pw.CloseWithError(exporter.Export(ctx, c.ContentStore(), desc, pw))
-	}()
-	return pr, nil
-}