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/update.go

@@ -0,0 +1,137 @@
+/*
+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 daemon
+
+import (
+	"fmt"
+
+	"github.com/golang/glog"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	utilerrors "k8s.io/apimachinery/pkg/util/errors"
+	intstrutil "k8s.io/apimachinery/pkg/util/intstr"
+	"k8s.io/kubernetes/pkg/api/v1"
+	extensions "k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
+	"k8s.io/kubernetes/pkg/controller/daemon/util"
+)
+
+// rollingUpdate deletes old daemon set pods making sure that no more than
+// ds.Spec.UpdateStrategy.RollingUpdate.MaxUnavailable pods are unavailable
+func (dsc *DaemonSetsController) rollingUpdate(ds *extensions.DaemonSet) error {
+	newPods, oldPods, err := dsc.getAllDaemonSetPods(ds)
+	allPods := append(oldPods, newPods...)
+
+	maxUnavailable, numUnavailable, err := dsc.getUnavailableNumbers(ds, allPods)
+	if err != nil {
+		return fmt.Errorf("Couldn't get unavailable numbers: %v", err)
+	}
+	oldAvailablePods, oldUnavailablePods := util.SplitByAvailablePods(ds.Spec.MinReadySeconds, oldPods)
+
+	// for oldPods delete all not running pods
+	var podsToDelete []string
+	glog.V(4).Infof("Marking all unavailable old pods for deletion")
+	for _, pod := range oldUnavailablePods {
+		// Skip terminating pods. We won't delete them again
+		if pod.DeletionTimestamp != nil {
+			continue
+		}
+		glog.V(4).Infof("Marking pod %s/%s for deletion", ds.Name, pod.Name)
+		podsToDelete = append(podsToDelete, pod.Name)
+	}
+
+	glog.V(4).Infof("Marking old pods for deletion")
+	for _, pod := range oldAvailablePods {
+		if numUnavailable >= maxUnavailable {
+			glog.V(4).Infof("Number of unavailable DaemonSet pods: %d, is equal to or exceeds allowed maximum: %d", numUnavailable, maxUnavailable)
+			break
+		}
+		glog.V(4).Infof("Marking pod %s/%s for deletion", ds.Name, pod.Name)
+		podsToDelete = append(podsToDelete, pod.Name)
+		numUnavailable++
+	}
+	errors := dsc.syncNodes(ds, podsToDelete, []string{})
+	return utilerrors.NewAggregate(errors)
+}
+
+func (dsc *DaemonSetsController) getAllDaemonSetPods(ds *extensions.DaemonSet) ([]*v1.Pod, []*v1.Pod, error) {
+	var newPods []*v1.Pod
+	var oldPods []*v1.Pod
+
+	selector, err := metav1.LabelSelectorAsSelector(ds.Spec.Selector)
+	if err != nil {
+		return newPods, oldPods, err
+	}
+	daemonPods, err := dsc.podLister.Pods(ds.Namespace).List(selector)
+	if err != nil {
+		return newPods, oldPods, fmt.Errorf("Couldn't get list of pods for daemon set %#v: %v", ds, err)
+	}
+	for _, pod := range daemonPods {
+		if util.IsPodUpdated(ds.TemplateGeneration, pod) {
+			newPods = append(newPods, pod)
+		} else {
+			oldPods = append(oldPods, pod)
+		}
+	}
+	return newPods, oldPods, nil
+}
+
+func (dsc *DaemonSetsController) getUnavailableNumbers(ds *extensions.DaemonSet, allPods []*v1.Pod) (int, int, error) {
+	glog.V(4).Infof("Getting unavailable numbers")
+	// TODO: get nodeList once in syncDaemonSet and pass it to other functions
+	nodeList, err := dsc.nodeLister.List(labels.Everything())
+	if err != nil {
+		return -1, -1, fmt.Errorf("couldn't get list of nodes during rolling update of daemon set %#v: %v", ds, err)
+	}
+
+	nodeToDaemonPods, err := dsc.getNodesToDaemonPods(ds)
+	if err != nil {
+		return -1, -1, fmt.Errorf("couldn't get node to daemon pods mapping for daemon set %#v: %v", ds, err)
+	}
+
+	var numUnavailable, desiredNumberScheduled int
+	for i := range nodeList {
+		node := nodeList[i]
+		wantToRun, _, _, err := dsc.nodeShouldRunDaemonPod(node, ds)
+		if err != nil {
+			return -1, -1, err
+		}
+		if !wantToRun {
+			continue
+		}
+		desiredNumberScheduled++
+		daemonPods, exists := nodeToDaemonPods[node.Name]
+		if !exists {
+			numUnavailable++
+			continue
+		}
+		available := false
+		for _, pod := range daemonPods {
+			if v1.IsPodAvailable(pod, ds.Spec.MinReadySeconds, metav1.Now()) {
+				available = true
+				break
+			}
+		}
+		if !available {
+			numUnavailable++
+		}
+	}
+	maxUnavailable, err := intstrutil.GetValueFromIntOrPercent(ds.Spec.UpdateStrategy.RollingUpdate.MaxUnavailable, desiredNumberScheduled, true)
+	if err != nil {
+		return -1, -1, fmt.Errorf("Invalid value for MaxUnavailable: %v", err)
+	}
+	return maxUnavailable, numUnavailable, nil
+}