DaemonSet updates

It implements https://github.com/kubernetes/community/blob/master/contributors/design-proposals/daemonset-update.md
Feature https://github.com/kubernetes/features/issues/124

pkg/controller/daemon/util/daemonset_util.go

@@ -0,0 +1,62 @@
+/*
+Copyright 2017 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 util
+
+import (
+	"fmt"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/v1"
+	extensions "k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
+	labelsutil "k8s.io/kubernetes/pkg/util/labels"
+)
+
+// GetPodTemplateWithHash returns copy of provided template with additional
+// label which contains hash of provided template
+func GetPodTemplateWithGeneration(template v1.PodTemplateSpec, generation int64) v1.PodTemplateSpec {
+	obj, _ := api.Scheme.DeepCopy(template)
+	newTemplate := obj.(v1.PodTemplateSpec)
+	templateGenerationStr := fmt.Sprint(generation)
+	newTemplate.ObjectMeta.Labels = labelsutil.CloneAndAddLabel(
+		template.ObjectMeta.Labels,
+		extensions.DaemonSetTemplateGenerationKey,
+		templateGenerationStr,
+	)
+	return newTemplate
+}
+
+// IsPodUpdate checks if pod contains label with provided hash
+func IsPodUpdated(dsTemplateGeneration int64, pod *v1.Pod) bool {
+	podTemplateGeneration, generationExists := pod.ObjectMeta.Labels[extensions.DaemonSetTemplateGenerationKey]
+	dsTemplateGenerationStr := fmt.Sprint(dsTemplateGeneration)
+	return generationExists && podTemplateGeneration == dsTemplateGenerationStr
+}
+
+// SplitByAvailablePods splits provided daemon set pods by availabilty
+func SplitByAvailablePods(minReadySeconds int32, pods []*v1.Pod) ([]*v1.Pod, []*v1.Pod) {
+	unavailablePods := []*v1.Pod{}
+	availablePods := []*v1.Pod{}
+	for _, pod := range pods {
+		if v1.IsPodAvailable(pod, minReadySeconds, metav1.Now()) {
+			availablePods = append(availablePods, pod)
+		} else {
+			unavailablePods = append(unavailablePods, pod)
+		}
+	}
+	return availablePods, unavailablePods
+}