fix(chartfile): add extra checks for chart name

Add extra checks in linter for chart names. Looks for invalid characters.

Signed-off-by: Lex Huismans <lexhuismans@outlook.com>

pkg/lint/rules/chartfile.go

@@ -21,6 +21,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
+	"regexp"
 
 	"github.com/Masterminds/semver/v3"
 	"github.com/asaskevich/govalidator"
@@ -104,9 +105,14 @@ func validateChartYamlFormat(chartFileError error) error {
 }
 
 func validateChartName(cf *chart.Metadata) error {
+	var validNameRegex = regexp.MustCompile(`^[a-z0-9](([-a-z0-9]*)?)$`)
+
 	if cf.Name == "" {
 		return errors.New("name is required")
 	}
+	if !validNameRegex.MatchString(cf.Name) {
+		return errors.New(fmt.Sprintf("invalid release name, must match regex %s", validNameRegex.String()))
+	}
 	return nil
 }
 

pkg/lint/rules/chartfile_test.go

@@ -30,11 +30,13 @@ import (
 )
 
 const (
+	goodChartDir       = "testdata/goodone"
 	badChartDir        = "testdata/badchartfile"
 	anotherBadChartDir = "testdata/anotherbadchartfile"
 )
 
 var (
+	goodChartFilePath        = filepath.Join(goodChartDir, "Chart.yaml")
 	badChartFilePath         = filepath.Join(badChartDir, "Chart.yaml")
 	nonExistingChartFilePath = filepath.Join(os.TempDir(), "Chart.yaml")
 )
@@ -65,9 +67,15 @@ func TestValidateChartYamlFormat(t *testing.T) {
 }
 
 func TestValidateChartName(t *testing.T) {
-	err := validateChartName(badChart)
+	badNameChart, _ := chartutil.LoadChartfile(goodChartFilePath)
-	if err == nil {
+	badName := &badNameChart.Name
-		t.Errorf("validateChartName to return a linter error, got no error")
+
+	for _, name := range []string{"", "with-Capital", "with_underscore"} {
+		*badName = name
+		err := validateChartName(badNameChart)
+		if err == nil {
+			t.Errorf("validateChartName to return a linter error for chart name %s, got no error", name)
+		}
 	}
 }