// CreateOrUpdate attempts to update the current etcd state with the provided
// allocation.
func (e *Etcd) CreateOrUpdate(snapshot *api.RangeAllocation) error {
e.lock.Lock()
defer e.lock.Unlock()
last := ""
err := e.helper.GuaranteedUpdate(e.baseKey, &api.RangeAllocation{}, true,
tools.SimpleUpdate(func(input runtime.Object) (output runtime.Object, err error) {
existing := input.(*api.RangeAllocation)
switch {
case len(snapshot.ResourceVersion) != 0 && len(existing.ResourceVersion) != 0:
if snapshot.ResourceVersion != existing.ResourceVersion {
return nil, k8serr.NewConflict(e.kind, "", fmt.Errorf("the provided resource version does not match"))
}
case len(existing.ResourceVersion) != 0:
return nil, k8serr.NewConflict(e.kind, "", fmt.Errorf("another caller has already initialized the resource"))
}
last = snapshot.ResourceVersion
return snapshot, nil
}),
)
if err != nil {
return etcderr.InterpretUpdateError(err, e.kind, "")
}
err = e.alloc.Restore(snapshot.Range, snapshot.Data)
if err == nil {
e.last = last
}
return err
}
// setPodHostAndAnnotations sets the given pod's host to 'machine' iff it was previously 'oldMachine' and merges
// the provided annotations with those of the pod.
// Returns the current state of the pod, or an error.
func (r *BindingREST) setPodHostAndAnnotations(ctx api.Context, podID, oldMachine, machine string, annotations map[string]string) (finalPod *api.Pod, err error) {
podKey, err := r.store.KeyFunc(ctx, podID)
if err != nil {
return nil, err
}
err = r.store.Helper.GuaranteedUpdate(podKey, &api.Pod{}, false, tools.SimpleUpdate(func(obj runtime.Object) (runtime.Object, error) {
pod, ok := obj.(*api.Pod)
if !ok {
return nil, fmt.Errorf("unexpected object: %#v", obj)
}
if pod.DeletionTimestamp != nil {
return nil, fmt.Errorf("pod %s is being deleted, cannot be assigned to a host", pod.Name)
}
if pod.Spec.NodeName != oldMachine {
return nil, fmt.Errorf("pod %v is already assigned to node %q", pod.Name, pod.Spec.NodeName)
}
pod.Spec.NodeName = machine
if pod.Annotations == nil {
pod.Annotations = make(map[string]string)
}
for k, v := range annotations {
pod.Annotations[k] = v
}
finalPod = pod
return pod, nil
}))
return finalPod, err
}
// tryUpdate performs a read-update to persist the latest snapshot state of allocation.
func (e *Etcd) tryUpdate(fn func() error) error {
err := e.helper.GuaranteedUpdate(e.baseKey, &api.RangeAllocation{}, true,
tools.SimpleUpdate(func(input runtime.Object) (output runtime.Object, err error) {
existing := input.(*api.RangeAllocation)
if len(existing.ResourceVersion) == 0 {
return nil, fmt.Errorf("cannot allocate resources of type %s at this time", e.kind)
}
if existing.ResourceVersion != e.last {
if err := e.alloc.Restore(existing.Range, existing.Data); err != nil {
return nil, err
}
if err := fn(); err != nil {
return nil, err
}
}
e.last = existing.ResourceVersion
rangeSpec, data := e.alloc.Snapshot()
existing.Range = rangeSpec
existing.Data = data
return existing, nil
}),
)
return etcderr.InterpretUpdateError(err, e.kind, "")
}