cell: Fail hive configuration on duplicate flags

When a hive declares the same configuration multiple times, only one of them will take effect. In order to prevent resultant bugs, instead detect and prevent such configuration in the first place. Signed-off-by: Joe Stringer <[email protected]>
cilium · Jan 18, 2025 · 6956598 · 6956598
1 parent 605c141
commit 6956598
Showing 1 changed file with 8 additions and 1 deletion.
diff --git a/cell/config.go b/cell/config.go
@@ -149,8 +149,15 @@ func (c *config[Cfg]) Apply(cont container, _ rootContainer) error {
 
 	// Register the flags to the global set of all flags.
 	err := cont.Invoke(
-		func(allFlags *pflag.FlagSet) {
+		func(allFlags *pflag.FlagSet) error {
+			var err error
+			flags.VisitAll(func(flag *pflag.Flag) {
+				if allFlags.Lookup(flag.Name) != nil {
+					err = fmt.Errorf("Duplicate flag %s", flag.Name)
+				}
+			})
 			allFlags.AddFlagSet(flags)
+			return err
 		})
 	if err != nil {
 		return err