rm: map keyspace service-limit errors to 403/500

Signed-off-by: okjiang <819421878@qq.com>

Author: okJiang

pkg/mcs/resourcemanager/server/apis/v1/api.go

@@ -376,7 +376,11 @@ func (s *Service) setKeyspaceServiceLimit(c *gin.Context) {
 	}
 	keyspaceID := rmserver.ExtractKeyspaceID(keyspaceIDValue)
 	if err := s.manager.SetKeyspaceServiceLimit(keyspaceID, req.ServiceLimit); err != nil {
-		c.String(http.StatusBadRequest, err.Error())
+		if rmserver.IsMetadataWriteDisabledError(err) {
+			c.String(http.StatusForbidden, err.Error())
+			return
+		}
+		c.String(http.StatusInternalServerError, err.Error())
 		return
 	}
 	c.String(http.StatusOK, "Success!")

pkg/mcs/resourcemanager/server/write_role.go

@@ -1,4 +1,4 @@
-// Copyright 2025 TiKV Project Authors.
+// Copyright 2026 TiKV Project Authors.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -39,3 +39,8 @@ func (r ResourceGroupWriteRole) AllowsStateWrite() bool {
 }
 
 var errMetadataWriteDisabled = errors.New("metadata write is disabled")
+
+// IsMetadataWriteDisabledError reports whether err is a metadata-write-disabled error.
+func IsMetadataWriteDisabledError(err error) bool {
+	return errors.ErrorEqual(err, errMetadataWriteDisabled)
+}