// etcdWatch calls etcd's Watch function, and handles any errors. Meant to be called
// as a goroutine.
func (w *etcdWatcher) etcdWatch(client tools.EtcdClient, key string, resourceVersion uint64) {
defer util.HandleCrash()
defer close(w.etcdError)
if resourceVersion == 0 {
latest, err := etcdGetInitialWatchState(client, key, w.list, w.etcdIncoming)
if err != nil {
w.etcdError <- err
return
}
resourceVersion = latest + 1
}
_, err := client.Watch(key, resourceVersion, w.list, w.etcdIncoming, w.etcdStop)
if err != nil && err != etcd.ErrWatchStoppedByUser {
w.etcdError <- err
}
}
// etcdGetInitialWatchState turns an etcd Get request into a watch equivalent
func etcdGetInitialWatchState(client tools.EtcdClient, key string, recursive bool, incoming chan<- *etcd.Response) (resourceVersion uint64, err error) {
resp, err := client.Get(key, false, recursive)
if err != nil {
if !IsEtcdNotFound(err) {
glog.Errorf("watch was unable to retrieve the current index for the provided key (%q): %v", key, err)
return resourceVersion, err
}
if index, ok := etcdErrorIndex(err); ok {
resourceVersion = index
}
return resourceVersion, nil
}
resourceVersion = resp.EtcdIndex
convertRecursiveResponse(resp.Node, resp, incoming)
return
}
func (s *SchedulerServer) fetchFrameworkID(client tools.EtcdClient) (*mesos.FrameworkID, error) {
if s.FailoverTimeout > 0 {
if response, err := client.Get(meta.FrameworkIDKey, false, false); err != nil {
if !etcdstorage.IsEtcdNotFound(err) {
return nil, fmt.Errorf("unexpected failure attempting to load framework ID from etcd: %v", err)
}
log.V(1).Infof("did not find framework ID in etcd")
} else if response.Node.Value != "" {
log.Infof("configuring FrameworkInfo with Id found in etcd: '%s'", response.Node.Value)
return mutil.NewFrameworkID(response.Node.Value), nil
}
} else {
//TODO(jdef) this seems like a totally hackish way to clean up the framework ID
if _, err := client.Delete(meta.FrameworkIDKey, true); err != nil {
if !etcdstorage.IsEtcdNotFound(err) {
return nil, fmt.Errorf("failed to delete framework ID from etcd: %v", err)
}
log.V(1).Infof("nothing to delete: did not find framework ID in etcd")
}
}
return nil, nil
}