Support metadata producer with underlying data.

plugin/pkg/scheduler/factory/plugins.go

@@ -46,6 +46,9 @@ type PluginFactoryArgs struct {
 	FailureDomains                 []string
 }
 
+// MetadataProducerFactory produces MetadataProducer from the given args.
+type MetadataProducerFactory func(PluginFactoryArgs) algorithm.MetadataProducer
+
 // A FitPredicateFactory produces a FitPredicate from the given args.
 type FitPredicateFactory func(PluginFactoryArgs) algorithm.FitPredicate
 
@@ -73,6 +76,8 @@ var (
 	fitPredicateMap      = make(map[string]FitPredicateFactory)
 	priorityFunctionMap  = make(map[string]PriorityConfigFactory)
 	algorithmProviderMap = make(map[string]AlgorithmProviderConfig)
+	// Registered metadata producers
+	priorityMetadataProducer MetadataProducerFactory
 )
 
 const (
@@ -148,6 +153,12 @@ func IsFitPredicateRegistered(name string) bool {
 	return ok
 }
 
+func RegisterPriorityMetadataProducerFactory(factory MetadataProducerFactory) {
+	schedulerFactoryMutex.Lock()
+	defer schedulerFactoryMutex.Unlock()
+	priorityMetadataProducer = factory
+}
+
 // DEPRECATED
 // Use Map-Reduce pattern for priority functions.
 // Registers a priority function with the algorithm registry. Returns the name,
@@ -283,6 +294,16 @@ func getFitPredicateFunctions(names sets.String, args PluginFactoryArgs) (map[st
 	return predicates, nil
 }
 
+func getPriorityMetadataProducer(args PluginFactoryArgs) (algorithm.MetadataProducer, error) {
+	schedulerFactoryMutex.Lock()
+	defer schedulerFactoryMutex.Unlock()
+
+	if priorityMetadataProducer == nil {
+		return algorithm.EmptyMetadataProducer, nil
+	}
+	return priorityMetadataProducer(args), nil
+}
+
 func getPriorityFunctionConfigs(names sets.String, args PluginFactoryArgs) ([]algorithm.PriorityConfig, error) {
 	schedulerFactoryMutex.Lock()
 	defer schedulerFactoryMutex.Unlock()