// updateRcWithRetries retries updating the given rc on conflict with the following steps:
// 1. Get latest resource
// 2. applyUpdate
// 3. Update the resource
func updateRcWithRetries(c client.Interface, namespace string, rc *api.ReplicationController, applyUpdate updateRcFunc) (*api.ReplicationController, error) {
// Deep copy the rc in case we failed on Get during retry loop
obj, err := api.Scheme.Copy(rc)
if err != nil {
return nil, fmt.Errorf("failed to deep copy rc before updating it: %v", err)
}
oldRc := obj.(*api.ReplicationController)
err = client.RetryOnConflict(client.DefaultBackoff, func() (e error) {
// Apply the update, then attempt to push it to the apiserver.
applyUpdate(rc)
if rc, e = c.ReplicationControllers(namespace).Update(rc); e == nil {
// rc contains the latest controller post update
return
}
updateErr := e
// Update the controller with the latest resource version, if the update failed we
// can't trust rc so use oldRc.Name.
if rc, e = c.ReplicationControllers(namespace).Get(oldRc.Name); e != nil {
// The Get failed: Value in rc cannot be trusted.
rc = oldRc
}
// Only return the error from update
return updateErr
})
// If the error is non-nil the returned controller cannot be trusted, if it is nil, the returned
// controller contains the applied update.
return rc, err
}
// updatePodWithRetries retries updating the given pod on conflict with the following steps:
// 1. Get latest resource
// 2. applyUpdate
// 3. Update the resource
func updatePodWithRetries(c client.Interface, namespace string, pod *api.Pod, applyUpdate updatePodFunc) (*api.Pod, error) {
// Deep copy the pod in case we failed on Get during retry loop
obj, err := api.Scheme.Copy(pod)
if err != nil {
return nil, fmt.Errorf("failed to deep copy pod before updating it: %v", err)
}
oldPod := obj.(*api.Pod)
err = client.RetryOnConflict(client.DefaultBackoff, func() (e error) {
// Apply the update, then attempt to push it to the apiserver.
applyUpdate(pod)
if pod, e = c.Pods(namespace).Update(pod); e == nil {
return
}
updateErr := e
if pod, e = c.Pods(namespace).Get(oldPod.Name); e != nil {
pod = oldPod
}
// Only return the error from update
return updateErr
})
// If the error is non-nil the returned pod cannot be trusted, if it is nil, the returned
// controller contains the applied update.
return pod, err
}