Backoff correctly when adopting replica sets/pods

pkg/controller/deployment/util/replicaset_util.go

@@ -0,0 +1,79 @@
+/*
+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 util
+
+import (
+	"fmt"
+
+	"github.com/golang/glog"
+
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/v1"
+	extensions "k8s.io/kubernetes/pkg/apis/extensions/v1beta1"
+	"k8s.io/kubernetes/pkg/client/cache"
+	unversionedextensions "k8s.io/kubernetes/pkg/client/clientset_generated/release_1_5/typed/extensions/v1beta1"
+	"k8s.io/kubernetes/pkg/client/retry"
+	errorsutil "k8s.io/kubernetes/pkg/util/errors"
+	labelsutil "k8s.io/kubernetes/pkg/util/labels"
+)
+
+// TODO: use client library instead when it starts to support update retries
+//       see https://github.com/kubernetes/kubernetes/issues/21479
+type updateRSFunc func(rs *extensions.ReplicaSet) error
+
+// UpdateRSWithRetries updates a RS with given applyUpdate function. Note that RS not found error is ignored.
+// The returned bool value can be used to tell if the RS is actually updated.
+func UpdateRSWithRetries(rsClient unversionedextensions.ReplicaSetInterface, rsLister *cache.StoreToReplicaSetLister, namespace, name string, applyUpdate updateRSFunc) (*extensions.ReplicaSet, error) {
+	var rs *extensions.ReplicaSet
+
+	retryErr := retry.RetryOnConflict(retry.DefaultBackoff, func() error {
+		var err error
+		rs, err = rsLister.ReplicaSets(namespace).Get(name)
+		if err != nil {
+			return err
+		}
+		obj, deepCopyErr := api.Scheme.DeepCopy(rs)
+		if deepCopyErr != nil {
+			return deepCopyErr
+		}
+		rs = obj.(*extensions.ReplicaSet)
+		// Apply the update, then attempt to push it to the apiserver.
+		if applyErr := applyUpdate(rs); applyErr != nil {
+			return applyErr
+		}
+		rs, err = rsClient.Update(rs)
+		return err
+	})
+
+	// Ignore the precondition violated error, but the RS isn't updated.
+	if retryErr == errorsutil.ErrPreconditionViolated {
+		glog.V(4).Infof("Replica set %s/%s precondition doesn't hold, skip updating it.", namespace, name)
+		retryErr = nil
+	}
+
+	return rs, retryErr
+}
+
+// GetReplicaSetHash returns the pod template hash of a ReplicaSet's pod template space
+func GetReplicaSetHash(rs *extensions.ReplicaSet) string {
+	meta := rs.Spec.Template.ObjectMeta
+	meta.Labels = labelsutil.CloneAndRemoveLabel(meta.Labels, extensions.DefaultDeploymentUniqueLabelKey)
+	return fmt.Sprintf("%d", GetPodTemplateSpecHash(v1.PodTemplateSpec{
+		ObjectMeta: meta,
+		Spec:       rs.Spec.Template.Spec,
+	}))
+}