fix: artifact gzip fixed

pkg/artifact/layer.go

@@ -2,11 +2,10 @@ package artifact
 
 import (
 	"bytes"
-	"fmt"
+	"io"
+
 	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/partial"
 	"github.com/google/go-containerregistry/pkg/v1/types"
-	"io"
 )
 
 type Layer = v1.Layer
@@ -43,26 +42,6 @@ func (a *artifact) Uncompressed() (io.ReadCloser, error) {
 	return a.uncompressed()
 }
 
-func Gzipped(l Layer) (Layer, error) {
-	gziped, err := partial.UncompressedToLayer(l)
-	if err != nil {
-		return gziped, nil
-	}
-	return &compressed{Layer: l}, nil
-}
-
-type compressed struct {
-	Layer
-}
-
-func (a *compressed) MediaType() (types.MediaType, error) {
-	m, err := a.Layer.MediaType()
-	if err != nil {
-		return "", err
-	}
-	return types.MediaType(fmt.Sprintf("%s+gzip", m)), nil
-}
-
 func WithDescriptor(l Layer, descriptor v1.Descriptor) Layer {
 	return &artifactWithDescriptor{
 		desc:  descriptor,

pkg/artifact/layer__compressed.go

@@ -0,0 +1,63 @@
+package artifact
+
+import (
+	"fmt"
+	"io"
+	"sync"
+
+	containerregistryv1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/google/go-containerregistry/pkg/v1/partial"
+	"github.com/google/go-containerregistry/pkg/v1/types"
+)
+
+func Gzipped(l Layer) (Layer, error) {
+	return &compressedLayerWithoutDiff{Layer: l}, nil
+}
+
+type compressedLayerWithoutDiff struct {
+	Layer
+
+	once          sync.Once
+	hash          containerregistryv1.Hash
+	size          int64
+	hashSizeError error
+}
+
+func (a *compressedLayerWithoutDiff) MediaType() (types.MediaType, error) {
+	m, err := a.Layer.MediaType()
+	if err != nil {
+		return "", err
+	}
+	return types.MediaType(fmt.Sprintf("%s+gzip", m)), nil
+}
+
+func (ule *compressedLayerWithoutDiff) Compressed() (io.ReadCloser, error) {
+	u, err := partial.UncompressedToLayer(ule.Layer)
+	if err != nil {
+		return nil, err
+	}
+	return u.Compressed()
+}
+
+func (ule *compressedLayerWithoutDiff) Digest() (containerregistryv1.Hash, error) {
+	ule.calcSizeHash()
+	return ule.hash, ule.hashSizeError
+}
+
+// Size implements v1.Layer
+func (ule *compressedLayerWithoutDiff) Size() (int64, error) {
+	ule.calcSizeHash()
+	return ule.size, ule.hashSizeError
+}
+
+func (ule *compressedLayerWithoutDiff) calcSizeHash() {
+	ule.once.Do(func() {
+		var r io.ReadCloser
+		r, ule.hashSizeError = ule.Compressed()
+		if ule.hashSizeError != nil {
+			return
+		}
+		defer r.Close()
+		ule.hash, ule.size, ule.hashSizeError = containerregistryv1.SHA256(r)
+	})
+}

pkg/artifact/layer__uncompressed.go

@@ -4,59 +4,58 @@ import (
 	"io"
 	"sync"
 
-	v1 "github.com/google/go-containerregistry/pkg/v1"
+	containerregistryv1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/types"
 )
 
 type UncompressedLayer interface {
 	MediaType() (types.MediaType, error)
-
 	Uncompressed() (io.ReadCloser, error)
 }
 
-func NonCompressedLayer(u UncompressedLayer) v1.Layer {
-	return &nonCompressedLayer{
+func NonCompressedLayer(u UncompressedLayer) containerregistryv1.Layer {
+	return &uncompressedLayer{
 		UncompressedLayer: u,
 	}
 }
 
-type nonCompressedLayer struct {
+type uncompressedLayer struct {
 	UncompressedLayer
 
 	hashSizeError error
-	hash          v1.Hash
+	hash          containerregistryv1.Hash
 	size          int64
 	once          sync.Once
 }
 
-func (a *nonCompressedLayer) DiffID() (v1.Hash, error) {
+func (a *uncompressedLayer) DiffID() (containerregistryv1.Hash, error) {
 	a.calcSizeHash()
 
 	return a.hash, a.hashSizeError
 }
 
-func (a *nonCompressedLayer) Size() (int64, error) {
+func (a *uncompressedLayer) Size() (int64, error) {
 	a.calcSizeHash()
 
 	return a.size, a.hashSizeError
 }
 
-func (a *nonCompressedLayer) Digest() (v1.Hash, error) {
-	return a.DiffID()
-}
-
-func (a *nonCompressedLayer) Compressed() (io.ReadCloser, error) {
-	return a.Uncompressed()
-}
-
-func (a *nonCompressedLayer) calcSizeHash() {
+func (a *uncompressedLayer) calcSizeHash() {
 	a.once.Do(func() {
 		r, err := a.Uncompressed()
 		if err != nil {
 			a.hashSizeError = err
 			return
 		}
 		defer r.Close()
-		a.hash, a.size, a.hashSizeError = v1.SHA256(r)
+		a.hash, a.size, a.hashSizeError = containerregistryv1.SHA256(r)
 	})
 }
+
+func (a *uncompressedLayer) Digest() (containerregistryv1.Hash, error) {
+	return a.DiffID()
+}
+
+func (a *uncompressedLayer) Compressed() (io.ReadCloser, error) {
+	return a.Uncompressed()
+}