Add pkg/v1/stream.NewLayer to stream layer contents

.travis.yml

@@ -7,6 +7,7 @@ language:
 
 go:
   - "1.10"
+  - "1.11"
 
 git:
   depth: 1

pkg/crane/append.go

@@ -18,13 +18,12 @@ import (
 	"log"
 	"net/http"
 
-	"github.com/spf13/cobra"
-
 	"github.com/google/go-containerregistry/pkg/authn"
 	"github.com/google/go-containerregistry/pkg/name"
 	"github.com/google/go-containerregistry/pkg/v1/mutate"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 	"github.com/google/go-containerregistry/pkg/v1/tarball"
+	"github.com/spf13/cobra"
 )
 
 func init() { Root.AddCommand(NewCmdAppend()) }

pkg/v1/mutate/mutate.go

@@ -29,6 +29,7 @@ import (
 	"github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
 	"github.com/google/go-containerregistry/pkg/v1/partial"
+	"github.com/google/go-containerregistry/pkg/v1/stream"
 	"github.com/google/go-containerregistry/pkg/v1/tarball"
 	"github.com/google/go-containerregistry/pkg/v1/types"
 	"github.com/google/go-containerregistry/pkg/v1/v1util"
@@ -58,77 +59,14 @@ func Append(base v1.Image, adds ...Addendum) (v1.Image, error) {
 	if len(adds) == 0 {
 		return base, nil
 	}
-
 	if err := validate(adds); err != nil {
 		return nil, err
 	}
 
-	m, err := base.Manifest()
-	if err != nil {
-		return nil, err
-	}
-
-	cf, err := base.ConfigFile()
-	if err != nil {
-		return nil, err
-	}
-
-	image := &image{
-		Image:      base,
-		manifest:   m.DeepCopy(),
-		configFile: cf.DeepCopy(),
-		diffIDMap:  make(map[v1.Hash]v1.Layer),
-		digestMap:  make(map[v1.Hash]v1.Layer),
-	}
-
-	diffIDs := image.configFile.RootFS.DiffIDs
-	history := image.configFile.History
-
-	for _, add := range adds {
-		diffID, err := add.Layer.DiffID()
-		if err != nil {
-			return nil, err
-		}
-		diffIDs = append(diffIDs, diffID)
-		history = append(history, add.History)
-		image.diffIDMap[diffID] = add.Layer
-	}
-
-	manifestLayers := image.manifest.Layers
-
-	for _, add := range adds {
-		d := v1.Descriptor{
-			MediaType: types.DockerLayer,
-		}
-
-		if d.Size, err = add.Layer.Size(); err != nil {
-			return nil, err
-		}
-
-		if d.Digest, err = add.Layer.Digest(); err != nil {
-			return nil, err
-		}
-
-		manifestLayers = append(manifestLayers, d)
-		image.digestMap[d.Digest] = add.Layer
-	}
-
-	image.configFile.RootFS.DiffIDs = diffIDs
-	image.configFile.History = history
-	image.manifest.Layers = manifestLayers
-
-	rcfg, err := image.RawConfigFile()
-	if err != nil {
-		return nil, err
-	}
-	d, sz, err := v1.SHA256(bytes.NewBuffer(rcfg))
-	if err != nil {
-		return nil, err
-	}
-	image.manifest.Config.Digest = d
-	image.manifest.Config.Size = sz
-
-	return image, nil
+	return &image{
+		base: base,
+		adds: adds,
+	}, nil
 }
 
 // Config mutates the provided v1.Image to have the provided v1.Config
@@ -150,10 +88,8 @@ func configFile(base v1.Image, cfg *v1.ConfigFile) (v1.Image, error) {
 	}
 
 	image := &image{
-		Image:      base,
-		manifest:   m.DeepCopy(),
-		configFile: cfg,
-		digestMap:  make(map[v1.Hash]v1.Layer),
+		base:     base,
+		manifest: m.DeepCopy(),
 	}
 
 	rcfg, err := image.RawConfigFile()
@@ -166,6 +102,7 @@ func configFile(base v1.Image, cfg *v1.ConfigFile) (v1.Image, error) {
 	}
 	image.manifest.Config.Digest = d
 	image.manifest.Config.Size = sz
+	image.configFile = cfg
 	return image, nil
 }
 
@@ -183,16 +120,113 @@ func CreatedAt(base v1.Image, created v1.Time) (v1.Image, error) {
 }
 
 type image struct {
-	v1.Image
+	base v1.Image
+	adds []Addendum
+
+	computed   bool
 	configFile *v1.ConfigFile
 	manifest   *v1.Manifest
 	diffIDMap  map[v1.Hash]v1.Layer
 	digestMap  map[v1.Hash]v1.Layer
 }
 
+var _ v1.Image = (*image)(nil)
+
+func (i *image) MediaType() (types.MediaType, error) { return i.base.MediaType() }
+
+func (i *image) compute() error {
+	// Don't re-compute if already computed.
+	if i.computed {
+		return nil
+	}
+	cf, err := i.base.ConfigFile()
+	if err != nil {
+		return err
+	}
+	configFile := cf.DeepCopy()
+	diffIDs := configFile.RootFS.DiffIDs
+	history := configFile.History
+
+	diffIDMap := make(map[v1.Hash]v1.Layer)
+	digestMap := make(map[v1.Hash]v1.Layer)
+
+	for _, add := range i.adds {
+		diffID, err := add.Layer.DiffID()
+		if err != nil {
+			return err
+		}
+		diffIDs = append(diffIDs, diffID)
+		history = append(history, add.History)
+		diffIDMap[diffID] = add.Layer
+	}
+
+	m, err := i.base.Manifest()
+	if err != nil {
+		return err
+	}
+	manifest := m.DeepCopy()
+	manifestLayers := manifest.Layers
+	for _, add := range i.adds {
+		d := v1.Descriptor{
+			MediaType: types.DockerLayer,
+		}
+
+		var err error
+		if d.Size, err = add.Layer.Size(); err != nil {
+			return err
+		}
+
+		if d.Digest, err = add.Layer.Digest(); err != nil {
+			return err
+		}
+
+		manifestLayers = append(manifestLayers, d)
+		digestMap[d.Digest] = add.Layer
+	}
+
+	configFile.RootFS.DiffIDs = diffIDs
+	configFile.History = history
+
+	manifest.Layers = manifestLayers
+
+	rcfg, err := json.Marshal(configFile)
+	if err != nil {
+		return err
+	}
+	d, sz, err := v1.SHA256(bytes.NewBuffer(rcfg))
+	if err != nil {
+		return err
+	}
+	manifest.Config.Digest = d
+	manifest.Config.Size = sz
+
+	i.configFile = configFile
+	i.manifest = manifest
+	i.diffIDMap = diffIDMap
+	i.digestMap = digestMap
+	i.computed = true
+	return nil
+}
+
 // Layers returns the ordered collection of filesystem layers that comprise this image.
 // The order of the list is oldest/base layer first, and most-recent/top layer last.
 func (i *image) Layers() ([]v1.Layer, error) {
+	if err := i.compute(); err == stream.ErrNotComputed {
+		// Image contains a streamable layer which has not yet been
+		// consumed. Just return the layers we have in case the caller
+		// is going to consume the layers.
+		layers, err := i.base.Layers()
+		if err != nil {
+			return nil, err
+		}
+		for _, add := range i.adds {
+			layers = append(layers, add.Layer)
+		}
+		return layers, nil
+	} else if err != nil {
+		return nil, err
+	}
+
 	diffIDs, err := partial.DiffIDs(i)
 	if err != nil {
 		return nil, err
@@ -210,36 +244,57 @@ func (i *image) Layers() ([]v1.Layer, error) {
 
 // BlobSet returns an unordered collection of all the blobs in the image.
 func (i *image) BlobSet() (map[v1.Hash]struct{}, error) {
+	if err := i.compute(); err != nil {
+		return nil, err
+	}
 	return partial.BlobSet(i)
 }
 
 // ConfigName returns the hash of the image's config file.
 func (i *image) ConfigName() (v1.Hash, error) {
+	if err := i.compute(); err != nil {
+		return v1.Hash{}, err
+	}
 	return partial.ConfigName(i)
 }
 
 // ConfigFile returns this image's config file.
 func (i *image) ConfigFile() (*v1.ConfigFile, error) {
+	if err := i.compute(); err != nil {
+		return nil, err
+	}
 	return i.configFile, nil
 }
 
 // RawConfigFile returns the serialized bytes of ConfigFile()
 func (i *image) RawConfigFile() ([]byte, error) {
+	if err := i.compute(); err != nil {
+		return nil, err
+	}
 	return json.Marshal(i.configFile)
 }
 
 // Digest returns the sha256 of this image's manifest.
 func (i *image) Digest() (v1.Hash, error) {
+	if err := i.compute(); err != nil {
+		return v1.Hash{}, err
+	}
 	return partial.Digest(i)
 }
 
 // Manifest returns this image's Manifest object.
 func (i *image) Manifest() (*v1.Manifest, error) {
+	if err := i.compute(); err != nil {
+		return nil, err
+	}
 	return i.manifest, nil
 }
 
 // RawManifest returns the serialized bytes of Manifest()
 func (i *image) RawManifest() ([]byte, error) {
+	if err := i.compute(); err != nil {
+		return nil, err
+	}
 	return json.Marshal(i.manifest)
 }
 
@@ -254,7 +309,7 @@ func (i *image) LayerByDigest(h v1.Hash) (v1.Layer, error) {
 	if layer, ok := i.digestMap[h]; ok {
 		return layer, nil
 	}
-	return i.Image.LayerByDigest(h)
+	return i.base.LayerByDigest(h)
 }
 
 // LayerByDiffID is an analog to LayerByDigest, looking up by "diff id"
@@ -263,7 +318,7 @@ func (i *image) LayerByDiffID(h v1.Hash) (v1.Layer, error) {
 	if layer, ok := i.diffIDMap[h]; ok {
 		return layer, nil
 	}
-	return i.Image.LayerByDiffID(h)
+	return i.base.LayerByDiffID(h)
 }
 
 func validate(adds []Addendum) error {