Unpack local image (#277)

* [WIP] Unpack local docker images

* unpack local image

* PR feedback + missing new function call

Co-authored-by: Ettore Di Giacinto <mudler@users.noreply.github.com>

cmd/util.go

@@ -107,7 +107,7 @@ func NewUnpackCommand() *cobra.Command {
 				util.DefaultContext.Error("Invalid path %s", destination)
 				os.Exit(1)
 			}
-
+			local, _ := cmd.Flags().GetBool("local")
 			verify, _ := cmd.Flags().GetBool("verify")
 			user, _ := cmd.Flags().GetString("auth-username")
 			pass, _ := cmd.Flags().GetString("auth-password")
@@ -126,6 +126,7 @@ func NewUnpackCommand() *cobra.Command {
 				RegistryToken: registryToken,
 			}
 
+			if !local {
 				info, err := docker.DownloadAndExtractDockerImage(util.DefaultContext, image, destination, auth, verify)
 				if err != nil {
 					util.DefaultContext.Error(err.Error())
@@ -133,6 +134,14 @@ func NewUnpackCommand() *cobra.Command {
 				}
 				util.DefaultContext.Info(fmt.Sprintf("Pulled: %s %s", info.Target.Digest, info.Name))
 				util.DefaultContext.Info(fmt.Sprintf("Size: %s", units.BytesSize(float64(info.Target.Size))))
+			} else {
+				info, err := docker.ExtractDockerImage(util.DefaultContext, image, destination)
+				if err != nil {
+					util.DefaultContext.Error(err.Error())
+					os.Exit(1)
+				}
+				util.DefaultContext.Info(fmt.Sprintf("Size: %s", units.BytesSize(float64(info.Target.Size))))
+			}
 		},
 	}
 
@@ -143,6 +152,7 @@ func NewUnpackCommand() *cobra.Command {
 	c.Flags().String("auth-identity-token", "", "Authentication identity token")
 	c.Flags().String("auth-registry-token", "", "Authentication registry token")
 	c.Flags().Bool("verify", false, "Verify signed images to notary before to pull")
+	c.Flags().Bool("local", false, "Unpack local image")
 	return c
 }
 

pkg/helpers/docker/docker.go

@@ -33,6 +33,7 @@ import (
 	"github.com/google/go-containerregistry/pkg/authn"
 	"github.com/google/go-containerregistry/pkg/name"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
+	"github.com/google/go-containerregistry/pkg/v1/daemon"
 	"github.com/mudler/luet/pkg/api/core/bus"
 	"github.com/opencontainers/go-digest"
 	specs "github.com/opencontainers/image-spec/specs-go/v1"
@@ -192,3 +193,60 @@ func DownloadAndExtractDockerImage(ctx luettypes.Context, image, dest string, au
 		},
 	}, nil
 }
+
+func ExtractDockerImage(ctx luettypes.Context, local, dest string)(*images.Image, error) {
+	if !fileHelper.Exists(dest) {
+		if err := os.MkdirAll(dest, os.ModePerm); err != nil {
+			return nil, errors.Wrapf(err, "cannot create destination directory")
+		}
+	}
+
+	ref, err := name.ParseReference(local)
+	if err != nil {
+		return nil, err
+	}
+
+	img, err := daemon.Image(ref)
+	if err != nil {
+		return nil, err
+	}
+
+	m, err := img.Manifest()
+	if err != nil {
+		return nil, err
+	}
+
+	mt, err := img.MediaType()
+	if err != nil {
+		return nil, err
+	}
+
+	d, err := img.Digest()
+	if err != nil {
+		return nil, err
+	}
+
+	var c int64
+	c, _, err = luetimages.ExtractTo(
+		ctx,
+		img,
+		dest,
+		nil,
+	)
+
+	if err != nil {
+		return nil, err
+	}
+
+	bus.Manager.Publish(bus.EventImagePostUnPack, UnpackEventData{Image: local, Dest: dest})
+
+	return &images.Image{
+		Name:   local,
+		Labels: m.Annotations,
+		Target: specs.Descriptor{
+			MediaType: string(mt),
+			Digest:    digest.Digest(d.String()),
+			Size:      c,
+		},
+	}, nil
+}