Support metadata producer with underlying data.

plugin/pkg/scheduler/algorithm/priorities/metadata.go

@@ -0,0 +1,49 @@
+/*
+Copyright 2016 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package priorities
+
+import (
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/plugin/pkg/scheduler/schedulercache"
+)
+
+// priorityMetadata is a type that is passed as metadata for priority functions
+type priorityMetadata struct {
+	nonZeroRequest *schedulercache.Resource
+	podTolerations []api.Toleration
+	affinity       *api.Affinity
+}
+
+func PriorityMetadata(pod *api.Pod) interface{} {
+	// If we cannot compute metadata, just return nil
+	if pod == nil {
+		return nil
+	}
+	tolerations, err := getTolerationListFromPod(pod)
+	if err != nil {
+		return nil
+	}
+	affinity, err := api.GetAffinityFromPodAnnotations(pod.Annotations)
+	if err != nil {
+		return nil
+	}
+	return &priorityMetadata{
+		nonZeroRequest: getNonZeroRequests(pod),
+		podTolerations: tolerations,
+		affinity:       affinity,
+	}
+}

plugin/pkg/scheduler/algorithm/priorities/priorities.go

@@ -29,33 +29,6 @@ import (
 	"k8s.io/kubernetes/plugin/pkg/scheduler/schedulercache"
 )
 
-// priorityMetadata is a type that is passed as metadata for priority functions
-type priorityMetadata struct {
-	nonZeroRequest *schedulercache.Resource
-	podTolerations []api.Toleration
-	affinity       *api.Affinity
-}
-
-func PriorityMetadata(pod *api.Pod) interface{} {
-	// If we cannot compute metadata, just return nil
-	if pod == nil {
-		return nil
-	}
-	tolerations, err := getTolerationListFromPod(pod)
-	if err != nil {
-		return nil
-	}
-	affinity, err := api.GetAffinityFromPodAnnotations(pod.Annotations)
-	if err != nil {
-		return nil
-	}
-	return &priorityMetadata{
-		nonZeroRequest: getNonZeroRequests(pod),
-		podTolerations: tolerations,
-		affinity:       affinity,
-	}
-}
-
 func getNonZeroRequests(pod *api.Pod) *schedulercache.Resource {
 	result := &schedulercache.Resource{}
 	for i := range pod.Spec.Containers {

plugin/pkg/scheduler/algorithm/types.go

@@ -38,6 +38,9 @@ type PriorityMapFunction func(pod *api.Pod, meta interface{}, nodeInfo *schedule
 // TODO: Change interface{} to a specific type.
 type PriorityReduceFunction func(pod *api.Pod, result schedulerapi.HostPriorityList) error
 
+// MetdataProducer is a function that computes metadata for a given pod.
+type MetadataProducer func(pod *api.Pod) interface{}
+
 // DEPRECATED
 // Use Map-Reduce pattern for priority functions.
 type PriorityFunction func(pod *api.Pod, nodeNameToInfo map[string]*schedulercache.NodeInfo, nodes []*api.Node) (schedulerapi.HostPriorityList, error)
@@ -51,6 +54,10 @@ type PriorityConfig struct {
 	Weight   int
 }
 
+func EmptyMetadataProducer(pod *api.Pod) interface{} {
+	return nil
+}
+
 type PredicateFailureReason interface {
 	GetReason() string
 }