Refactor, breaking API changes

Refactor api, DownloadImage is now DownloadAndUnpackImage and can specify
the prefered unpack method.
We should be now api stable for v0.x branch

api/download.go

@@ -18,9 +18,10 @@ const defaultRegistryBase = "https://registry-1.docker.io"
 type DownloadOpts struct {
 	RegistryBase string
 	KeepLayers   bool
+	UnpackMode   string
 }
 
-func DownloadImage(sourceImage, output string, opts *DownloadOpts) error {
+func DownloadAndUnpackImage(sourceImage, output string, opts *DownloadOpts) error {
 
 	if opts.RegistryBase == "" {
 		opts.RegistryBase = defaultRegistryBase
@@ -113,7 +114,7 @@ func DownloadImage(sourceImage, output string, opts *DownloadOpts) error {
 
 	jww.INFO.Println("Unpacking...")
 
-	err = export.UnPackLayers(layers_sha, output)
+	err = export.UnPackLayers(layers_sha, output, opts.UnpackMode)
 	if err != nil {
 		jww.INFO.Fatal(err)
 		return err

api/export.go

@@ -16,27 +16,21 @@ type Export struct {
 	Path    string
 }
 
-func (e *Export) ExtractLayers() error {
+func (e *Export) ExtractLayers(unpackmode string) error {
 
 	jww.INFO.Println("Extracting layers...")
 
 	for _, entry := range e.Entries {
 		jww.INFO.Println("  - ", entry.LayerTarPath)
-		err := entry.ExtractLayerDir()
+		err := entry.ExtractLayerDir(unpackmode)
 		if err != nil {
 			return err
 		}
 	}
 	return nil
 }
 
-func (e *Export) UnPackLayers(order []string, layerDir string) error {
-
-	unpackmode := os.Getenv("UNPACK_MODE")
-	if unpackmode == "" {
-		unpackmode = "umoci"
-	}
-
+func (e *Export) UnPackLayers(order []string, layerDir string, unpackmode string) error {
 	err := os.MkdirAll(layerDir, 0755)
 	if err != nil {
 		return err

api/image.go

@@ -48,15 +48,11 @@ func (e *ExportedImage) RemoveLayerDir() error {
 	return os.RemoveAll(e.LayerDirPath)
 }
 
-func (e *ExportedImage) ExtractLayerDir() error {
+func (e *ExportedImage) ExtractLayerDir(unpackmode string) error {
 	err := os.MkdirAll(e.LayerDirPath, 0755)
 	if err != nil {
 		return err
 	}
-	unpackmode := os.Getenv("UNPACK_MODE")
-	if unpackmode == "" {
-		unpackmode = "umoci"
-	}
 
 	if err := ExtractLayer(&ExtractOpts{
 		Source:       e.LayerTarPath,

download.go

@@ -1,6 +1,8 @@
 package main
 
 import (
+	"os"
+
 	"github.com/codegangsta/cli"
 	"github.com/mudler/docker-companion/api"
 )
@@ -15,6 +17,9 @@ func downloadImage(c *cli.Context) error {
 	} else {
 		return cli.NewExitError("This command requires to argument: source-image output-folder(absolute)", 86)
 	}
-
-	return api.DownloadImage(sourceImage, output, &api.DownloadOpts{KeepLayers: c.Bool("keep")})
+	unpackmode := os.Getenv("UNPACK_MODE")
+	if unpackmode == "" {
+		unpackmode = "umoci"
+	}
+	return api.DownloadAndUnpackImage(sourceImage, output, &api.DownloadOpts{KeepLayers: c.Bool("keep"), UnpackMode: unpackmode})
 }

main.go

@@ -8,7 +8,7 @@ import (
 )
 
 // VERSION is the app version
-const VERSION = "0.4.3"
+const VERSION = "0.4.5"
 
 func main() {
 	app := cli.NewApp()