Move controller manager build function to pkg/epp/server so we can better test it

Author: hzxuzhonghu

Diff for: cmd/epp/main.go

@@ -30,20 +30,12 @@ import (
 	"go.uber.org/zap/zapcore"
 	"google.golang.org/grpc"
 	healthPb "google.golang.org/grpc/health/grpc_health_v1"
-	corev1 "k8s.io/api/core/v1"
-	"k8s.io/apimachinery/pkg/fields"
-	"k8s.io/apimachinery/pkg/runtime"
-	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
-	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/client-go/rest"
 	"k8s.io/component-base/metrics/legacyregistry"
 	ctrl "sigs.k8s.io/controller-runtime"
-	"sigs.k8s.io/controller-runtime/pkg/cache"
-	"sigs.k8s.io/controller-runtime/pkg/client"
 	"sigs.k8s.io/controller-runtime/pkg/log/zap"
 	"sigs.k8s.io/controller-runtime/pkg/manager"
 	"sigs.k8s.io/controller-runtime/pkg/metrics/filters"
-	"sigs.k8s.io/gateway-api-inference-extension/api/v1alpha2"
 	"sigs.k8s.io/gateway-api-inference-extension/internal/runnable"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/backend"
 	"sigs.k8s.io/gateway-api-inference-extension/pkg/epp/backend/vllm"
@@ -101,15 +93,9 @@ var (
 			"are assumed to be named tls.crt and tls.key, respectively. If not set, and secureServing is enabled, "+
 			"then a self-signed certificate is used.")
 
-	scheme   = runtime.NewScheme()
 	setupLog = ctrl.Log.WithName("setup")
 )
 
-func init() {
-	utilruntime.Must(clientgoscheme.AddToScheme(scheme))
-	utilruntime.Must(v1alpha2.AddToScheme(scheme))
-}
-
 func main() {
 	if err := run(); err != nil {
 		os.Exit(1)
@@ -144,34 +130,9 @@ func run() error {
 		return err
 	}
 
-	mgr, err := ctrl.NewManager(cfg, ctrl.Options{
-		Scheme: scheme,
-		Cache: cache.Options{
-			ByObject: map[client.Object]cache.ByObject{
-				&corev1.Pod{}: {
-					Namespaces: map[string]cache.Config{
-						*poolNamespace: {},
-					},
-				},
-				&v1alpha2.InferencePool{}: {
-					Namespaces: map[string]cache.Config{
-						*poolNamespace: {
-							FieldSelector: fields.SelectorFromSet(fields.Set{
-								"metadata.name": *poolName,
-							}),
-						},
-					},
-				},
-				&v1alpha2.InferenceModel{}: {
-					Namespaces: map[string]cache.Config{
-						*poolNamespace: {},
-					},
-				},
-			},
-		},
-	})
+	mgr, err := runserver.NewDefaultManager(*poolNamespace, *poolName)
 	if err != nil {
-		setupLog.Error(err, "Failed to create controller manager", "config", cfg)
+		setupLog.Error(err, "Failed to create controller manager")
 		return err
 	}