Add scaffold for Yunikorn batch scheduler

pkg/batchscheduler/scheduler_manager.go

@@ -24,12 +24,14 @@ import (
 
 	"github.com/kubeflow/spark-operator/pkg/batchscheduler/interface"
 	"github.com/kubeflow/spark-operator/pkg/batchscheduler/volcano"
+	"github.com/kubeflow/spark-operator/pkg/batchscheduler/yunikorn"
 )
 
 type schedulerInitializeFunc func(config *rest.Config) (schedulerinterface.BatchScheduler, error)
 
 var schedulerContainers = map[string]schedulerInitializeFunc{
-	volcano.GetPluginName(): volcano.New,
+	volcano.GetPluginName():  volcano.New,
+	yunikorn.GetPluginName(): yunikorn.New,
 }
 
 func GetRegisteredNames() []string {

pkg/batchscheduler/yunikorn/yunikorn_scheduler.go

@@ -0,0 +1,37 @@
+package yunikorn
+
+import (
+	"k8s.io/client-go/rest"
+
+	"github.com/kubeflow/spark-operator/pkg/apis/sparkoperator.k8s.io/v1beta2"
+	schedulerinterface "github.com/kubeflow/spark-operator/pkg/batchscheduler/interface"
+)
+
+type YunikornBatchScheduler struct{}
+
+func GetPluginName() string {
+	return "yunikorn"
+}
+
+func (y *YunikornBatchScheduler) Name() string {
+	return GetPluginName()
+}
+
+func New(config *rest.Config) (schedulerinterface.BatchScheduler, error) {
+	return &YunikornBatchScheduler{}, nil
+}
+
+func (y *YunikornBatchScheduler) ShouldSchedule(app *v1beta2.SparkApplication) bool {
+	// Yunikorn doesn't require any additional resources to be created before scheduling
+	// since it gets all the information it needs from pod annotations
+	return true
+}
+
+func (y *YunikornBatchScheduler) CleanupOnCompletion(app *v1beta2.SparkApplication) error {
+	// No additional resources are created so nothing to clean up
+	return nil
+}
+
+func (y *YunikornBatchScheduler) DoBatchSchedulingOnSubmission(app *v1beta2.SparkApplication) error {
+	return nil
+}