client: make ImageImportResult an interface

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

client/image_import.go

@@ -2,18 +2,24 @@ package client
 
 import (
 	"context"
+	"io"
 	"net/url"
 
 	"github.com/distribution/reference"
 )
 
+// ImageImportResult holds the response body returned by the daemon for image import.
+type ImageImportResult interface {
+	io.ReadCloser
+}
+
 // ImageImport creates a new image based on the source options.
 // It returns the JSON content in the response body.
 func (cli *Client) ImageImport(ctx context.Context, source ImageImportSource, ref string, options ImageImportOptions) (ImageImportResult, error) {
 	if ref != "" {
 		// Check if the given image name can be resolved
 		if _, err := reference.ParseNormalizedNamed(ref); err != nil {
-			return ImageImportResult{}, err
+			return nil, err
 		}
 	}
 
@@ -40,7 +46,32 @@ func (cli *Client) ImageImport(ctx context.Context, source ImageImportSource, re
 
 	resp, err := cli.postRaw(ctx, "/images/create", query, source.Source, nil)
 	if err != nil {
-		return ImageImportResult{}, err
+		return nil, err
 	}
-	return ImageImportResult{rc: resp.Body}, nil
+	return &imageImportResult{body: resp.Body}, nil
+}
+
+// ImageImportResult holds the response body returned by the daemon for image import.
+type imageImportResult struct {
+	// body must be closed to avoid a resource leak
+	body io.ReadCloser
+}
+
+var (
+	_ io.ReadCloser     = (*imageImportResult)(nil)
+	_ ImageImportResult = (*imageImportResult)(nil)
+)
+
+func (r *imageImportResult) Read(p []byte) (int, error) {
+	if r == nil || r.body == nil {
+		return 0, io.EOF
+	}
+	return r.body.Read(p)
+}
+
+func (r *imageImportResult) Close() error {
+	if r == nil || r.body == nil {
+		return nil
+	}
+	return r.body.Close()
 }

client/image_import_opts.go

@@ -19,22 +19,3 @@ type ImageImportOptions struct {
 	Changes  []string         // Changes are the raw changes to apply to this image
 	Platform ocispec.Platform // Platform is the target platform of the image
 }
-
-// ImageImportResult holds the response body returned by the daemon for image import.
-type ImageImportResult struct {
-	rc io.ReadCloser
-}
-
-func (r ImageImportResult) Read(p []byte) (n int, err error) {
-	if r.rc == nil {
-		return 0, io.EOF
-	}
-	return r.rc.Read(p)
-}
-
-func (r ImageImportResult) Close() error {
-	if r.rc == nil {
-		return nil
-	}
-	return r.rc.Close()
-}

vendor/github.com/moby/moby/client/image_import.go

@@ -2,18 +2,24 @@ package client
 
 import (
 	"context"
+	"io"
 	"net/url"
 
 	"github.com/distribution/reference"
 )
 
+// ImageImportResult holds the response body returned by the daemon for image import.
+type ImageImportResult interface {
+	io.ReadCloser
+}
+
 // ImageImport creates a new image based on the source options.
 // It returns the JSON content in the response body.
 func (cli *Client) ImageImport(ctx context.Context, source ImageImportSource, ref string, options ImageImportOptions) (ImageImportResult, error) {
 	if ref != "" {
 		// Check if the given image name can be resolved
 		if _, err := reference.ParseNormalizedNamed(ref); err != nil {
-			return ImageImportResult{}, err
+			return nil, err
 		}
 	}
 
@@ -40,7 +46,32 @@ func (cli *Client) ImageImport(ctx context.Context, source ImageImportSource, re
 
 	resp, err := cli.postRaw(ctx, "/images/create", query, source.Source, nil)
 	if err != nil {
-		return ImageImportResult{}, err
+		return nil, err
 	}
-	return ImageImportResult{rc: resp.Body}, nil
+	return &imageImportResult{body: resp.Body}, nil
+}
+
+// ImageImportResult holds the response body returned by the daemon for image import.
+type imageImportResult struct {
+	// body must be closed to avoid a resource leak
+	body io.ReadCloser
+}
+
+var (
+	_ io.ReadCloser     = (*imageImportResult)(nil)
+	_ ImageImportResult = (*imageImportResult)(nil)
+)
+
+func (r *imageImportResult) Read(p []byte) (int, error) {
+	if r == nil || r.body == nil {
+		return 0, io.EOF
+	}
+	return r.body.Read(p)
+}
+
+func (r *imageImportResult) Close() error {
+	if r == nil || r.body == nil {
+		return nil
+	}
+	return r.body.Close()
 }

vendor/github.com/moby/moby/client/image_import_opts.go

@@ -19,22 +19,3 @@ type ImageImportOptions struct {
 	Changes  []string         // Changes are the raw changes to apply to this image
 	Platform ocispec.Platform // Platform is the target platform of the image
 }
-
-// ImageImportResult holds the response body returned by the daemon for image import.
-type ImageImportResult struct {
-	rc io.ReadCloser
-}
-
-func (r ImageImportResult) Read(p []byte) (n int, err error) {
-	if r.rc == nil {
-		return 0, io.EOF
-	}
-	return r.rc.Read(p)
-}
-
-func (r ImageImportResult) Close() error {
-	if r.rc == nil {
-		return nil
-	}
-	return r.rc.Close()
-}