Fix: Ignore alias validation error for index load

Signed-off-by: George Jenkins <gvjenkins@gmail.com>
(cherry picked from commit 68294fd)

pkg/repo/index.go

@@ -366,7 +366,7 @@ func loadIndex(data []byte, source string) (*IndexFile, error) {
 			if cvs[idx].APIVersion == "" {
 				cvs[idx].APIVersion = chart.APIVersionV1
 			}
-			if err := cvs[idx].Validate(); err != nil {
+			if err := cvs[idx].Validate(); ignoreSkippableChartValidationError(err) != nil {
 				log.Printf("skipping loading invalid entry for chart %q %q from %s: %s", name, cvs[idx].Version, source, err)
 				cvs = append(cvs[:idx], cvs[idx+1:]...)
 			}
@@ -392,3 +392,23 @@ func jsonOrYamlUnmarshal(b []byte, i interface{}) error {
 	}
 	return yaml.UnmarshalStrict(b, i)
 }
+
+// ignoreSkippableChartValidationError inspect the given error and returns nil if
+// the error isn't important for index loading
+//
+// In particular, charts may introduce validations that don't impact repository indexes
+// And repository indexes may be generated by older/non-complient software, which doesn't
+// conform to all validations.
+func ignoreSkippableChartValidationError(err error) error {
+	verr, ok := err.(chart.ValidationError)
+	if !ok {
+		return err
+	}
+
+	// https://github.com/helm/helm/issues/12748 (JFrog repository strips alias field)
+	if strings.HasPrefix(verr.Error(), "validation: more than one dependency with name or alias") {
+		return nil
+	}
+
+	return err
+}

pkg/repo/index_test.go

@@ -20,6 +20,7 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"fmt"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -596,3 +597,50 @@ func TestAddFileIndexEntriesNil(t *testing.T) {
 		}
 	}
 }
+
+func TestIgnoreSkippableChartValidationError(t *testing.T) {
+	type TestCase struct {
+		Input        error
+		ErrorSkipped bool
+	}
+	testCases := map[string]TestCase{
+		"nil": {
+			Input: nil,
+		},
+		"generic_error": {
+			Input: fmt.Errorf("foo"),
+		},
+		"non_skipped_validation_error": {
+			Input: chart.ValidationError("chart.metadata.type must be application or library"),
+		},
+		"skipped_validation_error": {
+			Input:        chart.ValidationErrorf("more than one dependency with name or alias %q", "foo"),
+			ErrorSkipped: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			result := ignoreSkippableChartValidationError(tc.Input)
+
+			if tc.Input == nil {
+				if result != nil {
+					t.Error("")
+				}
+				return
+			}
+
+			if tc.ErrorSkipped {
+				if result != nil {
+					t.Error("")
+				}
+				return
+			}
+
+			if tc.Input != result {
+				t.Error("")
+			}
+
+		})
+	}
+}