From 0c730b99979efba71586660dfae30bb905873248 Mon Sep 17 00:00:00 2001
From: Rashad Sirajudeen <rashad.20@cse.mrt.ac.lk>
Date: Fri, 19 Apr 2024 15:43:15 +0530
Subject: [PATCH] dove into the layers, making progress

---
 pkg/client/create_builder.go | 101 ++++++++++++++++++++++-------------
 1 file changed, 63 insertions(+), 38 deletions(-)

diff --git a/pkg/client/create_builder.go b/pkg/client/create_builder.go
index d8f2c210e..1d28d64f9 100644
--- a/pkg/client/create_builder.go
+++ b/pkg/client/create_builder.go
@@ -21,7 +21,6 @@ import (
 	"github.com/buildpacks/pack/internal/builder"
 	"github.com/buildpacks/pack/internal/paths"
 	"github.com/buildpacks/pack/internal/style"
-	"github.com/buildpacks/pack/pkg/blob"
 	"github.com/buildpacks/pack/pkg/buildpack"
 	"github.com/buildpacks/pack/pkg/image"
 )
@@ -223,7 +222,7 @@ func (c *Client) fetchLifecycle(ctx context.Context, config pubbldr.LifecycleCon
 			return nil, err
 		}
 		var lifecycleImage imgutil.Image
-		var blob blob.Blob
+		// var blob blob.Blob
 		imageName := buildpack.ParsePackageLocator(config.URI)
 		c.logger.Debugf("Downloading lifecycle image: %s", style.Symbol(imageName))
 
@@ -234,50 +233,76 @@ func (c *Client) fetchLifecycle(ctx context.Context, config pubbldr.LifecycleCon
 		}
 
 		// Good till this point
-
-		lifecycleImageTar := filepath.Join(relativeBaseDir, "lifecycle-image.tar")
-		lifecycleImageReader, err := c.docker.ImageSave(context.Background(), []string{lifecycleImage.Name()})
-		if err != nil {
-			return nil, err
-		}
-		defer lifecycleImageReader.Close()
-		lifecycleImageWriter, err := os.Create(lifecycleImageTar)
+		layers, err := lifecycleImage.UnderlyingImage().Layers()
 		if err != nil {
 			return nil, err
 		}
-		defer lifecycleImageWriter.Close()
-		if _, err = io.Copy(lifecycleImageWriter, lifecycleImageReader); err != nil {
-			return nil, err
-		}
-		lifecycleLayerName, err := LifecycleLayerName(lifecycleImageTar)
-		if err != nil {
-			return nil, err
-		}
-		if lifecycleLayerName == "" {
-			return nil, errors.New("failed to find lifecycle layer")
-		}
 
-		lifecycleLayerTar, err := LifecycleLayerTar(lifecycleImageTar, lifecycleLayerName)
-		if err != nil {
-			return nil, err
-		}
-
-		strippedTar, err := stripTopLevelDir(lifecycleLayerTar)
-		if err != nil {
-			return nil, err
-		}
+		for _, layer := range layers {
+			diffID, err := layer.DiffID()
+			if err != nil {
+				return nil, err
+			}
+			layerContent, err := lifecycleImage.GetLayer(diffID.String())
+			if err != nil {
+				panic(err)
+			}
+			defer layerContent.Close()
+
+			// Extract the layer tarball
+			tarReader := tar.NewReader(layerContent)
+			fmt.Println("--------------------------")
+			fmt.Print(diffID)
+			fmt.Println("--------------------------")
+
+			for {
+				header, err := tarReader.Next()
+				if err == io.EOF {
+					break // End of archive
+				}
+				if err != nil {
+					panic(err)
+				}
 
-		blob, err = c.downloader.Download(ctx, strippedTar)
-		if err != nil {
-			return nil, errors.Wrap(err, "downloading lifecycle")
-		}
+				if header.Name == "cnb" && header.Typeflag == tar.TypeDir {
+					fmt.Println(header.Name)
+				}
+			}
+			fmt.Println("--------------------------")
 
-		lifecycle, err := builder.NewLifecycle(blob)
-		if err != nil {
-			return nil, errors.Wrap(err, "invalid lifecycle")
 		}
 
-		return lifecycle, nil
+		// lifecycleImageTar := filepath.Join(relativeBaseDir, "lifecycle-image.tar")
+		// lifecycleImageReader, err := c.docker.ImageSave(context.Background(), []string{lifecycleImage.Name()})
+		// if err != nil {
+		// 	return nil, err
+		// }
+		// defer lifecycleImageReader.Close()
+		// lifecycleImageWriter, err := os.Create(lifecycleImageTar)
+		// if err != nil {
+		// 	return nil, err
+		// }
+		// defer lifecycleImageWriter.Close()
+		// if _, err = io.Copy(lifecycleImageWriter, lifecycleImageReader); err != nil {
+		// 	return nil, err
+		// }
+		// lifecycleLayerName, err := LifecycleLayerName(lifecycleImageTar)
+		// if err != nil {
+		// 	return nil, err
+		// }
+		// if lifecycleLayerName == "" {
+		// 	return nil, errors.New("failed to find lifecycle layer")
+		// }
+
+		// lifecycleLayerTar, err := LifecycleLayerTar(lifecycleImageTar, lifecycleLayerName)
+		// if err != nil {
+		// 	return nil, err
+		// }
+
+		// uri, err = stripTopLevelDir(lifecycleLayerTar)
+		// if err != nil {
+		// 	return nil, err
+		// }
 
 	case config.Version != "":
 		v, err := semver.NewVersion(config.Version)