func (t *tracker) addList(obj runtime.Object, replaceExisting bool) error { list, err := meta.ExtractList(obj) if err != nil { return err } errs := runtime.DecodeList(list, t.decoder) if len(errs) > 0 { return errs[0] } for _, obj := range list { err := t.add(obj, replaceExisting) if err != nil { return err } } return nil }
// TODO: check for watch expired error and retry watch from latest point? Same issue exists for Until. func ListWatchUntil(timeout time.Duration, lw ListerWatcher, conditions ...watch.ConditionFunc) (*watch.Event, error) { if len(conditions) == 0 { return nil, nil } list, err := lw.List(api.ListOptions{}) if err != nil { return nil, err } initialItems, err := meta.ExtractList(list) if err != nil { return nil, err } // use the initial items as simulated "adds" var lastEvent *watch.Event currIndex := 0 passedConditions := 0 for _, condition := range conditions { // check the next condition against the previous event and short circuit waiting for the next watch if lastEvent != nil { done, err := condition(*lastEvent) if err != nil { return lastEvent, err } if done { passedConditions = passedConditions + 1 continue } } ConditionSucceeded: for currIndex < len(initialItems) { lastEvent = &watch.Event{Type: watch.Added, Object: initialItems[currIndex]} currIndex++ done, err := condition(*lastEvent) if err != nil { return lastEvent, err } if done { passedConditions = passedConditions + 1 break ConditionSucceeded } } } if passedConditions == len(conditions) { return lastEvent, nil } remainingConditions := conditions[passedConditions:] metaObj, err := meta.ListAccessor(list) if err != nil { return nil, err } currResourceVersion := metaObj.GetResourceVersion() watchInterface, err := lw.Watch(api.ListOptions{ResourceVersion: currResourceVersion}) if err != nil { return nil, err } return watch.Until(timeout, watchInterface, remainingConditions...) }
// ListAndWatch first lists all items and get the resource version at the moment of call, // and then use the resource version to watch. // It returns error if ListAndWatch didn't even try to initialize watch. func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error { glog.V(3).Infof("Listing and watching %v from %s", r.expectedType, r.name) var resourceVersion string resyncCh, cleanup := r.resyncChan() defer cleanup() // Explicitly set "0" as resource version - it's fine for the List() // to be served from cache and potentially be delayed relative to // etcd contents. Reflector framework will catch up via Watch() eventually. options := api.ListOptions{ResourceVersion: "0"} list, err := r.listerWatcher.List(options) if err != nil { return fmt.Errorf("%s: Failed to list %v: %v", r.name, r.expectedType, err) } listMetaInterface, err := meta.ListAccessor(list) if err != nil { return fmt.Errorf("%s: Unable to understand list result %#v: %v", r.name, list, err) } resourceVersion = listMetaInterface.GetResourceVersion() items, err := meta.ExtractList(list) if err != nil { return fmt.Errorf("%s: Unable to understand list result %#v (%v)", r.name, list, err) } if err := r.syncWith(items, resourceVersion); err != nil { return fmt.Errorf("%s: Unable to sync list result: %v", r.name, err) } r.setLastSyncResourceVersion(resourceVersion) resyncerrc := make(chan error, 1) go func() { for { select { case <-resyncCh: case <-stopCh: return } glog.V(4).Infof("%s: forcing resync", r.name) if err := r.store.Resync(); err != nil { resyncerrc <- err return } cleanup() resyncCh, cleanup = r.resyncChan() } }() for { timemoutseconds := int64(minWatchTimeout.Seconds() * (rand.Float64() + 1.0)) options = api.ListOptions{ ResourceVersion: resourceVersion, // We want to avoid situations of hanging watchers. Stop any wachers that do not // receive any events within the timeout window. TimeoutSeconds: &timemoutseconds, } w, err := r.listerWatcher.Watch(options) if err != nil { switch err { case io.EOF: // watch closed normally case io.ErrUnexpectedEOF: glog.V(1).Infof("%s: Watch for %v closed with unexpected EOF: %v", r.name, r.expectedType, err) default: utilruntime.HandleError(fmt.Errorf("%s: Failed to watch %v: %v", r.name, r.expectedType, err)) } // If this is "connection refused" error, it means that most likely apiserver is not responsive. // It doesn't make sense to re-list all objects because most likely we will be able to restart // watch where we ended. // If that's the case wait and resend watch request. if urlError, ok := err.(*url.Error); ok { if opError, ok := urlError.Err.(*net.OpError); ok { if errno, ok := opError.Err.(syscall.Errno); ok && errno == syscall.ECONNREFUSED { time.Sleep(time.Second) continue } } } return nil } if err := r.watchHandler(w, &resourceVersion, resyncerrc, stopCh); err != nil { if err != errorStopRequested { glog.Warningf("%s: watch of %v ended with: %v", r.name, r.expectedType, err) } return nil } } }