Part 1 of pr #33763: cleanup CheckServiceAffinity in preparation for

predicate injection support, Update metadata struct

plugin/pkg/scheduler/algorithm/predicates/utils.go

@@ -0,0 +1,64 @@
+/*
+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 predicates
+
+import "k8s.io/kubernetes/pkg/labels"
+import "k8s.io/kubernetes/pkg/api"
+
+// FindLabelsInSet gets as many key/value pairs as possible out of a label set.
+func FindLabelsInSet(labelsToKeep []string, selector labels.Set) map[string]string {
+	aL := make(map[string]string)
+	for _, l := range labelsToKeep {
+		if selector.Has(l) {
+			aL[l] = selector.Get(l)
+		}
+	}
+	return aL
+}
+
+// AddUnsetLabelsToMap backfills missing values with values we find in a map.
+func AddUnsetLabelsToMap(aL map[string]string, labelsToAdd []string, labelSet labels.Set) {
+	for _, l := range labelsToAdd {
+		// if the label is already there, dont overwrite it.
+		if _, exists := aL[l]; exists {
+			continue
+		}
+		// otherwise, backfill this label.
+		if labelSet.Has(l) {
+			aL[l] = labelSet.Get(l)
+		}
+	}
+}
+
+// FilterPodsByNamespace filters pods outside a namespace from the given list.
+func FilterPodsByNamespace(pods []*api.Pod, ns string) []*api.Pod {
+	filtered := []*api.Pod{}
+	for _, nsPod := range pods {
+		if nsPod.Namespace == ns {
+			filtered = append(filtered, nsPod)
+		}
+	}
+	return filtered
+}
+
+// CreateSelectorFromLabels is used to define a selector that corresponds to the keys in a map.
+func CreateSelectorFromLabels(aL map[string]string) labels.Selector {
+	if aL == nil || len(aL) == 0 {
+		return labels.Everything()
+	}
+	return labels.Set(aL).AsSelector()
+}