[WIP] [YUNIKORN-2180] Clean up scheduler state initialization

- Moved all state initialization code into context
- Unified primary and secondary scheduler caches
- Properly handle orphaned pods (those referring to unknown nodes)
- TODO: Missing tests

pkg/cache/amprotocol.go

@@ -24,45 +24,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-// app management protocol defines all the APIs needed for app management,
-// this is the protocol between scheduler cache and app management plugins
-type ApplicationManagementProtocol interface {
-	// returns app that already existed in the cache,
-	// or nil, false if app with the given appID is not found
-	GetApplication(appID string) *Application
-
-	// add app to the context, app manager needs to provide all
-	// necessary app metadata through this call. If this a existing app
-	// for recovery, the AddApplicationRequest#Recovery must be true.
-	AddApplication(request *AddApplicationRequest) *Application
-
-	// remove application from the context
-	// returns an error if for some reason the app cannot be removed,
-	// e.g the given app is not found in current context.
-	RemoveApplication(appID string) error
-
-	// add task to the context, if add is successful,
-	AddTask(request *AddTaskRequest) *Task
-
-	// remove task from the app
-	// return an error if for some reason the task cannot be removed
-	// e.g app that owns this task is not found in context.
-	RemoveTask(appID, taskID string)
-
-	// notify the context that an app is completed,
-	// this will trigger some consequent operations for the given app
-	NotifyApplicationComplete(appID string)
-
-	// notify the context that an app has failed,
-	// this will trigger some consequent operations for the given app
-	NotifyApplicationFail(appID string)
-
-	// notify the context that an task is completed,
-	// this will trigger some consequent operations for a given task,
-	// e.g release the allocations that assigned for this task.
-	NotifyTaskComplete(appID, taskID string)
-}
-
 type AddApplicationRequest struct {
 	Metadata ApplicationMetadata
 }

pkg/cache/application.go

@@ -326,8 +326,12 @@ func (app *Application) SetState(state string) {
 	app.sm.SetState(state)
 }
 
+func (app *Application) TriggerAppSubmission() error {
+	return app.handle(NewSubmitApplicationEvent(app.applicationID))
+}
+
 func (app *Application) TriggerAppRecovery() error {
-	return app.handle(NewSimpleApplicationEvent(app.applicationID, RecoverApplication))
+	return app.handle(NewRecoverApplicationEvent(app.applicationID))
 }
 
 // Schedule is called in every scheduling interval,
@@ -339,12 +343,6 @@ func (app *Application) TriggerAppRecovery() error {
 // return true if the app needs scheduling or false if not
 func (app *Application) Schedule() bool {
 	switch app.GetApplicationState() {
-	case ApplicationStates().New:
-		ev := NewSubmitApplicationEvent(app.GetApplicationID())
-		if err := app.handle(ev); err != nil {
-			log.Log(log.ShimCacheApplication).Warn("failed to handle SUBMIT app event",
-				zap.Error(err))
-		}
 	case ApplicationStates().Accepted:
 		// once the app is accepted by the scheduler core,
 		// the next step is to send requests for scheduling
@@ -404,7 +402,7 @@ func (app *Application) scheduleTasks(taskScheduleCondition func(t *Task) bool)
 	}
 }
 
-func (app *Application) handleSubmitApplicationEvent() {
+func (app *Application) handleSubmitApplicationEvent() error {
 	log.Log(log.ShimCacheApplication).Info("handle app submission",
 		zap.Stringer("app", app),
 		zap.String("clusterID", conf.GetSchedulerConf().ClusterID))
@@ -433,9 +431,10 @@ func (app *Application) handleSubmitApplicationEvent() {
 		log.Log(log.ShimCacheApplication).Warn("failed to submit app", zap.Error(err))
 		dispatcher.Dispatch(NewFailApplicationEvent(app.applicationID, err.Error()))
 	}
+	return err
 }
 
-func (app *Application) handleRecoverApplicationEvent() {
+func (app *Application) handleRecoverApplicationEvent() error {
 	log.Log(log.ShimCacheApplication).Info("handle app recovering",
 		zap.Stringer("app", app),
 		zap.String("clusterID", conf.GetSchedulerConf().ClusterID))
@@ -464,6 +463,7 @@ func (app *Application) handleRecoverApplicationEvent() {
 		log.Log(log.ShimCacheApplication).Warn("failed to recover app", zap.Error(err))
 		dispatcher.Dispatch(NewFailApplicationEvent(app.applicationID, err.Error()))
 	}
+	return err
 }
 
 func (app *Application) skipReservationStage() bool {

pkg/cache/application_state.go

@@ -166,6 +166,13 @@ func NewSubmitApplicationEvent(appID string) SubmitApplicationEvent {
 	}
 }
 
+func NewRecoverApplicationEvent(appID string) SubmitApplicationEvent {
+	return SubmitApplicationEvent{
+		applicationID: appID,
+		event:         RecoverApplication,
+	}
+}
+
 func (se SubmitApplicationEvent) GetEvent() string {
 	return se.event.String()
 }
@@ -517,11 +524,11 @@ func newAppState() *fsm.FSM { //nolint:funlen
 			},
 			SubmitApplication.String(): func(_ context.Context, event *fsm.Event) {
 				app := event.Args[0].(*Application) //nolint:errcheck
-				app.handleSubmitApplicationEvent()
+				event.Err = app.handleSubmitApplicationEvent()
 			},
 			RecoverApplication.String(): func(_ context.Context, event *fsm.Event) {
 				app := event.Args[0].(*Application) //nolint:errcheck
-				app.handleRecoverApplicationEvent()
+				event.Err = app.handleRecoverApplicationEvent()
 			},
 			RejectApplication.String(): func(_ context.Context, event *fsm.Event) {
 				app := event.Args[0].(*Application) //nolint:errcheck