Namespace restricted mode (#147)

cli/errormessage/errormessage.go

@@ -0,0 +1,29 @@
+package errormessage
+
+import (
+	"errors"
+	"fmt"
+	regexpsyntax "regexp/syntax"
+
+	k8serrors "k8s.io/apimachinery/pkg/api/errors"
+)
+
+// formatError wraps error with a detailed message that is meant for the user.
+// While the errors are meant to be displayed, they are not meant to be exported as classes outsite of CLI.
+func FormatError(err error) error {
+	var errorNew error
+	if k8serrors.IsForbidden(err) {
+		errorNew = fmt.Errorf("Insufficient permissions: %w. Supply the required permission or control Mizu's access to namespaces by setting MizuNamespace in the config file or setting the tapped namespace with --set mizu-namespace=<NAMEPSACE>.", err)
+	} else if syntaxError, isSyntaxError := asRegexSyntaxError(err); isSyntaxError {
+		errorNew = fmt.Errorf("Regex %s is invalid: %w", syntaxError.Expr, err)
+	} else {
+		errorNew = err
+	}
+
+	return errorNew
+}
+
+func asRegexSyntaxError(err error) (*regexpsyntax.Error, bool) {
+	var syntaxError *regexpsyntax.Error
+	return syntaxError, errors.As(err, &syntaxError)
+}