Deployment to stop adding pod-template-hash labels/selector on adoption

This commit is contained in:
Janet Kuo 2018-03-23 15:50:16 -07:00
parent 9bd4f12c33
commit 647d8d8a22
2 changed files with 0 additions and 100 deletions

View File

@ -29,7 +29,6 @@ go_library(
"//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/labels:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/types:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/util/errors:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/util/rand:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
"//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",

View File

@ -28,7 +28,6 @@ import (
"k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
utilerrors "k8s.io/apimachinery/pkg/util/errors"
"k8s.io/apimachinery/pkg/util/rand"
"k8s.io/kubernetes/pkg/controller"
deploymentutil "k8s.io/kubernetes/pkg/controller/deployment/util"
@ -117,11 +116,6 @@ func (dc *DeploymentController) checkPausedConditions(d *extensions.Deployment)
// Note that currently the deployment controller is using caches to avoid querying the server for reads.
// This may lead to stale reads of replica sets, thus incorrect deployment status.
func (dc *DeploymentController) getAllReplicaSetsAndSyncRevision(d *extensions.Deployment, rsList []*extensions.ReplicaSet, podMap map[types.UID]*v1.PodList, createIfNotExisted bool) (*extensions.ReplicaSet, []*extensions.ReplicaSet, error) {
// List the deployment's RSes & Pods and apply pod-template-hash info to deployment's adopted RSes/Pods
rsList, err := dc.rsAndPodsWithHashKeySynced(d, rsList, podMap)
if err != nil {
return nil, nil, fmt.Errorf("error labeling replica sets and pods with pod-template-hash: %v", err)
}
_, allOldRSs := deploymentutil.FindOldReplicaSets(d, rsList)
// Get new replica set with the updated revision number
@ -133,99 +127,6 @@ func (dc *DeploymentController) getAllReplicaSetsAndSyncRevision(d *extensions.D
return newRS, allOldRSs, nil
}
// rsAndPodsWithHashKeySynced returns the RSes and pods the given deployment
// targets, with pod-template-hash information synced.
//
// rsList should come from getReplicaSetsForDeployment(d).
// podMap should come from getPodMapForDeployment(d, rsList).
func (dc *DeploymentController) rsAndPodsWithHashKeySynced(d *extensions.Deployment, rsList []*extensions.ReplicaSet, podMap map[types.UID]*v1.PodList) ([]*extensions.ReplicaSet, error) {
var syncedRSList []*extensions.ReplicaSet
for _, rs := range rsList {
// Add pod-template-hash information if it's not in the RS.
// Otherwise, new RS produced by Deployment will overlap with pre-existing ones
// that aren't constrained by the pod-template-hash.
syncedRS, err := dc.addHashKeyToRSAndPods(rs, podMap[rs.UID], d.Status.CollisionCount)
if err != nil {
return nil, err
}
syncedRSList = append(syncedRSList, syncedRS)
}
return syncedRSList, nil
}
// addHashKeyToRSAndPods adds pod-template-hash information to the given rs, if it's not already there, with the following steps:
// 1. Add hash label to the rs's pod template, and make sure the controller sees this update so that no orphaned pods will be created
// 2. Add hash label to all pods this rs owns, wait until replicaset controller reports rs.Status.FullyLabeledReplicas equal to the desired number of replicas
// 3. Add hash label to the rs's label and selector
func (dc *DeploymentController) addHashKeyToRSAndPods(rs *extensions.ReplicaSet, podList *v1.PodList, collisionCount *int32) (*extensions.ReplicaSet, error) {
// If the rs already has the new hash label in its selector, it's done syncing
if labelsutil.SelectorHasLabel(rs.Spec.Selector, extensions.DefaultDeploymentUniqueLabelKey) {
return rs, nil
}
hash, err := deploymentutil.GetReplicaSetHash(rs, collisionCount)
if err != nil {
return nil, err
}
// 1. Add hash template label to the rs. This ensures that any newly created pods will have the new label.
updatedRS, err := deploymentutil.UpdateRSWithRetries(dc.client.ExtensionsV1beta1().ReplicaSets(rs.Namespace), dc.rsLister, rs.Namespace, rs.Name,
func(updated *extensions.ReplicaSet) error {
// Precondition: the RS doesn't contain the new hash in its pod template label.
if updated.Spec.Template.Labels[extensions.DefaultDeploymentUniqueLabelKey] == hash {
return utilerrors.ErrPreconditionViolated
}
updated.Spec.Template.Labels = labelsutil.AddLabel(updated.Spec.Template.Labels, extensions.DefaultDeploymentUniqueLabelKey, hash)
return nil
})
if err != nil {
return nil, fmt.Errorf("error updating replica set %s/%s pod template label with template hash: %v", rs.Namespace, rs.Name, err)
}
// Make sure rs pod template is updated so that it won't create pods without the new label (orphaned pods).
if updatedRS.Generation > updatedRS.Status.ObservedGeneration {
// TODO: Revisit if we really need to wait here as opposed to returning and
// potentially unblocking this worker (can wait up to 1min before timing out).
if err = deploymentutil.WaitForReplicaSetUpdated(dc.rsLister, updatedRS.Generation, updatedRS.Namespace, updatedRS.Name); err != nil {
return nil, fmt.Errorf("error waiting for replica set %s/%s to be observed by controller: %v", updatedRS.Namespace, updatedRS.Name, err)
}
glog.V(4).Infof("Observed the update of replica set %s/%s's pod template with hash %s.", rs.Namespace, rs.Name, hash)
}
// 2. Update all pods managed by the rs to have the new hash label, so they will be correctly adopted.
if err := deploymentutil.LabelPodsWithHash(podList, dc.client, dc.podLister, rs.Namespace, rs.Name, hash); err != nil {
return nil, fmt.Errorf("error in adding template hash label %s to pods %+v: %s", hash, podList, err)
}
// We need to wait for the replicaset controller to observe the pods being
// labeled with pod template hash. Because previously we've called
// WaitForReplicaSetUpdated, the replicaset controller should have dropped
// FullyLabeledReplicas to 0 already, we only need to wait it to increase
// back to the number of replicas in the spec.
// TODO: Revisit if we really need to wait here as opposed to returning and
// potentially unblocking this worker (can wait up to 1min before timing out).
if err := deploymentutil.WaitForPodsHashPopulated(dc.rsLister, updatedRS.Generation, updatedRS.Namespace, updatedRS.Name); err != nil {
return nil, fmt.Errorf("Replica set %s/%s: error waiting for replicaset controller to observe pods being labeled with template hash: %v", updatedRS.Namespace, updatedRS.Name, err)
}
// 3. Update rs label and selector to include the new hash label
// Copy the old selector, so that we can scrub out any orphaned pods
updatedRS, err = deploymentutil.UpdateRSWithRetries(dc.client.ExtensionsV1beta1().ReplicaSets(rs.Namespace), dc.rsLister, rs.Namespace, rs.Name, func(updated *extensions.ReplicaSet) error {
// Precondition: the RS doesn't contain the new hash in its label and selector.
if updated.Labels[extensions.DefaultDeploymentUniqueLabelKey] == hash && updated.Spec.Selector.MatchLabels[extensions.DefaultDeploymentUniqueLabelKey] == hash {
return utilerrors.ErrPreconditionViolated
}
updated.Labels = labelsutil.AddLabel(updated.Labels, extensions.DefaultDeploymentUniqueLabelKey, hash)
updated.Spec.Selector = labelsutil.AddLabelToSelector(updated.Spec.Selector, extensions.DefaultDeploymentUniqueLabelKey, hash)
return nil
})
// If the RS isn't actually updated, that's okay, we'll retry in the
// next sync loop since its selector isn't updated yet.
if err != nil {
return nil, fmt.Errorf("error updating ReplicaSet %s/%s label and selector with template hash: %v", updatedRS.Namespace, updatedRS.Name, err)
}
// TODO: look for orphaned pods and label them in the background somewhere else periodically
return updatedRS, nil
}
// Returns a replica set that matches the intent of the given deployment. Returns nil if the new replica set doesn't exist yet.
// 1. Get existing new RS (the RS that the given deployment targets, whose pod template is the same as deployment's).
// 2. If there's existing new RS, update its revision number if it's smaller than (maxOldRevision + 1), where maxOldRevision is the max revision number among all old RSes.