tidy code

Signed-off-by: Kuromesi <[email protected]>

pkg/ext-proc/main.go

@@ -207,7 +207,7 @@ func startExternalProcessorServer(
 ) *grpc.Server {
 	svr := grpc.NewServer()
 
-	var orchestrator *scheduling.FilterOrchestratorImpl
+	var orchestrator scheduling.FilterOrchestrator
 	if *enableFilterConfiguration {
 		orchestrator = scheduling.NewFilterOrchestrator(datastore)
 	}

pkg/ext-proc/scheduling/orchestrate.go

@@ -19,6 +19,21 @@ func NewFilterOrchestrator(datastore *backend.K8sDatastore) *FilterOrchestratorI
 	}
 }
 
+func NewDefaultFilterOrchestrator() *DefaultFilterOrchestrator {
+	return &DefaultFilterOrchestrator{}
+}
+
+// DefaultFilterOrchestrator is a filter orchestrator that returns the default filter chain
+type DefaultFilterOrchestrator struct{}
+
+var _ FilterOrchestrator = &DefaultFilterOrchestrator{}
+
+func (DefaultFilterOrchestrator) Orchestrate() FilterChain {
+	return defaultFilter
+}
+
+// FilterOrchestratorImpl is a filter orchestrator that reads the filter configuration
+// from configmap and orchestrate the filter chain
 type FilterOrchestratorImpl struct {
 	datastore    *backend.K8sDatastore
 	lastUpdated  string

pkg/ext-proc/scheduling/scheduler.go

@@ -94,7 +94,7 @@ func NewScheduler(pmp PodMetricsProvider, opts ...SchedulerOption) *Scheduler {
 	s := &Scheduler{
 		podMetricsProvider: pmp,
 		filter:             defaultFilter,
-		filterOrchestrator: &FilterOrchestratorImpl{},
+		filterOrchestrator: NewDefaultFilterOrchestrator(),
 	}
 
 	for _, opt := range opts {
@@ -105,7 +105,9 @@ func NewScheduler(pmp PodMetricsProvider, opts ...SchedulerOption) *Scheduler {
 
 func WithOrchestrator(orchestrator FilterOrchestrator) SchedulerOption {
 	return func(s *Scheduler) {
-		s.filterOrchestrator = orchestrator
+		if orchestrator != nil {
+			s.filterOrchestrator = orchestrator
+		}
 	}
 }