A mapping from predicates/priorities to pluing configuration.

This PR only implements the mapping, but does not use it. A followup PR will use this mapping to produce a framework configuration that redirects mapped predicates/priorites to be exected as plugins.

pkg/scheduler/framework/plugins/default_registry.go

@@ -17,6 +17,9 @@ limitations under the License.
 package plugins
 
 import (
+	"fmt"
+
+	"k8s.io/kubernetes/pkg/scheduler/apis/config"
 	noop "k8s.io/kubernetes/pkg/scheduler/framework/plugins/noop"
 	framework "k8s.io/kubernetes/pkg/scheduler/framework/v1alpha1"
 )
@@ -31,3 +34,47 @@ func NewDefaultRegistry() framework.Registry {
 		noop.Name: noop.New,
 	}
 }
+
+// ConfigProducerArgs contains arguments that are passed to the producer.
+// As we add more predicates/priorities to framework plugins mappings, more arguments
+// may be added here.
+type ConfigProducerArgs struct {
+	// Weight used for priority functions.
+	Weight int32
+}
+
+// ConfigProducer produces a framework's configuration.
+type ConfigProducer func(args ConfigProducerArgs) (config.Plugins, []config.PluginConfig)
+
+// ConfigProducerRegistry tracks mappings from predicates/priorities to framework config producers.
+type ConfigProducerRegistry struct {
+	// maps that associate predicates/priorities with framework plugin configurations.
+	PredicateToConfigProducer map[string]ConfigProducer
+	PriorityToConfigProducer  map[string]ConfigProducer
+}
+
+// NewConfigProducerRegistry creates a new producer registry.
+func NewConfigProducerRegistry() *ConfigProducerRegistry {
+	return &ConfigProducerRegistry{
+		PredicateToConfigProducer: make(map[string]ConfigProducer),
+		PriorityToConfigProducer:  make(map[string]ConfigProducer),
+	}
+}
+
+func registerProducer(name string, producer ConfigProducer, producersMap map[string]ConfigProducer) error {
+	if _, exist := producersMap[name]; exist {
+		return fmt.Errorf("already registered %q", name)
+	}
+	producersMap[name] = producer
+	return nil
+}
+
+// RegisterPredicate registers a config producer for a predicate.
+func (f *ConfigProducerRegistry) RegisterPredicate(name string, producer ConfigProducer) error {
+	return registerProducer(name, producer, f.PredicateToConfigProducer)
+}
+
+// RegisterPriority registers a framework config producer for a priority.
+func (f *ConfigProducerRegistry) RegisterPriority(name string, producer ConfigProducer) error {
+	return registerProducer(name, producer, f.PriorityToConfigProducer)
+}