files: improve error for uncompressed Helm .tar archives

files/error.go

@@ -38,6 +38,7 @@ var (
 	ErrInvalidHelmChartCode                        = "meshkit-11292"
 	ErrInvalidDockerComposeCode                    = "meshkit-11293"
 	ErrInvalidKustomizationCode                    = "meshkit-11294"
+	ErrUncompressedTarCode                         = "meshkit-11305"
 	ErrFileTypeNotSupportedForDesignConversionCode = "meshkit-11300"
 )
 
@@ -260,6 +261,22 @@ func ErrInvalidHelmChart(fileName string, err error) error {
 	return errors.New(ErrInvalidHelmChartCode, errors.Critical, sdescription, ldescription, probableCause, remedy)
 }
 
+// ErrUncompressedTar returns an error explaining that Helm requires
+// compressed tarballs (tgz / tar.gz) and that an uncompressed .tar was provided.
+func ErrUncompressedTar(fileName string, err error) error {
+	return errors.New(
+		ErrUncompressedTarCode,
+		errors.Critical,
+		[]string{fmt.Sprintf("The file '%s' appears to be an uncompressed TAR archive.", fileName)},
+		[]string{fmt.Sprintf("Helm expects chart archives to be compressed (e.g., .tgz or .tar.gz). Error details: %s", err.Error())},
+		[]string{"The archive was created as an uncompressed .tar, but Helm requires compressed archives."},
+		[]string{
+			"Compress the .tar file to .tgz or .tar.gz and try again.",
+			"Create the Helm chart archive using 'helm package' or gzip the archive before uploading.",
+		},
+	)
+}
+
 func ErrInvalidDockerCompose(fileName string, err error) error {
 	sdescription := []string{
 		fmt.Sprintf("The file '%s' is not a valid Docker Compose file.", fileName),

files/identification.go

@@ -3,11 +3,13 @@ package files
 import (
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"os"
 	"path/filepath"
 	"strings"
+	"compress/gzip"
 
 	"github.com/meshery/meshkit/encoding"
 	"github.com/meshery/meshkit/models/oci"
@@ -298,11 +300,16 @@ func ParseFileAsHelmChart(file SanitizedFile) (*chart.Chart, error) {
 		return nil, fmt.Errorf("Invalid file extension %s", file.FileExt)
 	}
 
-	// Use Helm's loader.LoadDir to load the chart
-	// This function automatically handles nested directories and locates Chart.yaml
+	// Use Helm's loader.LoadArchive to load the chart
+	// This function expects a gzipped tar archive for charts (tgz / tar.gz)
 	chart, err := loader.LoadArchive(bytes.NewReader(file.RawData))
 	if err != nil {
-		return nil, fmt.Errorf("failed to load Helm chart  %v", err)
+		// If the file extension was an uncompressed .tar and the loader failed
+		// due to gzip/invalid header, provide a human friendly hint.
+		if file.FileExt == ".tar" && errors.Is(err, gzip.ErrHeader) {
+			return nil, ErrUncompressedTar(file.FileName, err)
+		}
+		return nil, ErrInvalidHelmChart(file.FileName, err)
 	}
 
 	// Validate the chart (optional but recommended)

files/tests/sanitization_test.go

@@ -1,6 +1,8 @@
 package files_test
 
 import (
+	"archive/tar"
+	"bytes"
 	"os"
 	"path/filepath"
 	"testing"
@@ -192,3 +194,55 @@ func TestSanitizeFile(t *testing.T) {
 		})
 	}
 }
+
+// Test that providing an uncompressed .tar containing a Helm chart yields the
+// helpful ErrUncompressedTarProvided (which uses ErrInvalidHelmChartCode).
+func TestUncompressedHelmTarError(t *testing.T) {
+	// Build an in-memory uncompressed tar with a Chart.yaml
+	var buf bytes.Buffer
+	tw := tar.NewWriter(&buf)
+	chartYAML := []byte("apiVersion: v2\nname: test-chart\nversion: 0.1.0\n")
+	hdr := &tar.Header{
+		Name: "Chart.yaml",
+		Mode: 0600,
+		Size: int64(len(chartYAML)),
+	}
+	if err := tw.WriteHeader(hdr); err != nil {
+		t.Fatalf("failed to write tar header: %v", err)
+	}
+	if _, err := tw.Write(chartYAML); err != nil {
+		t.Fatalf("failed to write chart content: %v", err)
+	}
+	if err := tw.Close(); err != nil {
+		t.Fatalf("failed to close tar writer: %v", err)
+	}
+
+	tempDir, err := os.MkdirTemp("", "temp-tests")
+	if err != nil {
+		t.Fatalf("failed to create temp directory: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	validExts := map[string]bool{
+		".json": true,
+		".yml":  true,
+		".yaml": true,
+		".tar":  true,
+		".tgz":  true,
+		".gz":   true,
+		".zip":  true,
+	}
+
+	sanitized, err := files.SanitizeFile(buf.Bytes(), "uncompressed-helm.tar", tempDir, validExts)
+	if err != nil {
+		t.Fatalf("unexpected sanitize error: %v", err)
+	}
+
+	_, err = files.ParseFileAsHelmChart(sanitized)
+	if err == nil {
+		t.Fatalf("expected error when parsing uncompressed tar as helm chart, got nil")
+	}
+	if errors.GetCode(err) != files.ErrUncompressedTarCode {
+		t.Fatalf("expected error code %s, got %s (err: %v)", files.ErrUncompressedTarCode, errors.GetCode(err), err)
+	}
+}