Nydusify: get nydus-image/nydusd path from env

So that allow specifying the path from env by make command.

Signed-off-by: Yan Song <[email protected]>

contrib/nydusify/pkg/nydusify/convert.go

@@ -45,6 +45,14 @@ type MergeOption struct {
 	PrefetchPatterns string
 }
 
+func getBuilder() string {
+	builderPath := os.Getenv(envNydusBuilder)
+	if builderPath == "" {
+		builderPath = "nydus-image"
+	}
+	return builderPath
+}
+
 // Unpack a OCI formatted tar stream into a directory.
 func unpackOciTar(ctx context.Context, dst string, reader io.Reader) error {
 	ds, err := compression.DecompressStream(reader)
@@ -218,12 +226,8 @@ func Convert(ctx context.Context, src io.Reader, opt ConvertOption) (io.ReadClos
 	bootstrapPath := filepath.Join(workDir, "bootstrap")
 	blobPath := filepath.Join(workDir, "blob")
 
-	builderPath := os.Getenv(envNydusBuilder)
-	if builderPath == "" {
-		builderPath = "nydus-image"
-	}
 	if err := tool.Convert(tool.ConvertOption{
-		BuilderPath: builderPath,
+		BuilderPath: getBuilder(),
 
 		BootstrapPath:    bootstrapPath,
 		BlobPath:         blobPath,
@@ -294,7 +298,7 @@ func Merge(ctx context.Context, layers []Layer, opt MergeOption) (reader io.Read
 	targetBootstrapPath := filepath.Join(workDir, "bootstrap")
 
 	if err := tool.Merge(tool.MergeOption{
-		BuilderPath: "nydus-image",
+		BuilderPath: getBuilder(),
 
 		SourceBootstrapPaths: sourceBootstrapPaths,
 		TargetBootstrapPath:  targetBootstrapPath,

contrib/nydusify/pkg/nydusify/convert_test.go

@@ -23,6 +23,8 @@ import (
 	"github.com/dragonflyoss/image-service/contrib/nydusify/pkg/nydusify/tool"
 )
 
+const envNydusdPath = "NYDUS_NYDUSD"
+
 func hugeString(size int) string {
 	var buf strings.Builder
 	buf.Grow(size)
@@ -172,9 +174,13 @@ func convertLayer(t *testing.T, source io.ReadCloser, chunkDict, workDir string)
 func verify(t *testing.T, workDir string) {
 	mountDir := filepath.Join(workDir, "mnt")
 	blobDir := filepath.Join(workDir, "blobs")
+	nydusdPath := os.Getenv(envNydusdPath)
+	if nydusdPath == "" {
+		nydusdPath = "nydusd"
+	}
 	config := tool.NydusdConfig{
 		EnablePrefetch: true,
-		NydusdPath:     "nydusd",
+		NydusdPath:     nydusdPath,
 		BootstrapPath:  filepath.Join(workDir, "bootstrap"),
 		ConfigPath:     filepath.Join(workDir, "nydusd-config.json"),
 		BackendType:    "localfs",