feat: WATCH_NAMESPACE support multi namespace

Signed-off-by: drivebyer <wuyangmuc@gmail.com>

main.go

@@ -19,6 +19,8 @@ package main
 import (
 	"flag"
 	"os"
+	"sigs.k8s.io/controller-runtime/pkg/cache"
+	"strings"
 
 	redisv1beta1 "github.com/OT-CONTAINER-KIT/redis-operator/api/v1beta1"
 	redisv1beta2 "github.com/OT-CONTAINER-KIT/redis-operator/api/v1beta2"
@@ -29,7 +31,6 @@ import (
 	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
 	ctrl "sigs.k8s.io/controller-runtime"
-	"sigs.k8s.io/controller-runtime/pkg/cache"
 	"sigs.k8s.io/controller-runtime/pkg/healthz"
 	"sigs.k8s.io/controller-runtime/pkg/log/zap"
 	"sigs.k8s.io/controller-runtime/pkg/metrics/server"
@@ -86,8 +87,13 @@ func main() {
 		LeaderElectionID:       "6cab913b.redis.opstreelabs.in",
 	}
 
-	if ns := os.Getenv("WATCH_NAMESPACE"); ns != "" {
-		options.Cache.DefaultNamespaces = map[string]cache.Config{ns: {}}
+	if namespaces := strings.TrimSpace(os.Getenv("WATCH_NAMESPACE")); namespaces != "" {
+		options.Cache.DefaultNamespaces = map[string]cache.Config{}
+		for _, ns := range strings.Split(namespaces, ",") {
+			if ns = strings.TrimSpace(ns); ns != "" {
+				options.Cache.DefaultNamespaces[ns] = cache.Config{}
+			}
+		}
 	}
 
 	mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), options)