func watch(client *etcd.Client, idx uint64, etcdchan chan *etcd.Response, key string, stop chan bool) {
for true {
select {
case <-stop:
log.V(1).Infof("Gracefully closing etcd watch loop: key=%s", key)
return
default:
log.V(1).Infof("Creating etcd watcher: key=%s, index=%d, machines=%s", key, idx, strings.Join(client.GetCluster(), ","))
resp, err := client.Watch(key, idx, true, nil, nil)
if err == nil {
idx = resp.Node.ModifiedIndex + 1
etcdchan <- resp
continue
}
log.Errorf("etcd watcher returned error: key=%s, err=\"%s\"", key, err.Error())
etcdError, ok := err.(*etcd.EtcdError)
if !ok {
// Let's not slam the etcd server in the event that we know
// an unexpected error occurred.
time.Sleep(time.Second)
continue
}
switch etcdError.ErrorCode {
case etcdErr.EcodeEventIndexCleared:
// This is racy, but adding one to the last known index
// will help get this watcher back into the range of
// etcd's internal event history
idx = idx + 1
default:
// Let's not slam the etcd server in the event that we know
// an unexpected error occurred.
time.Sleep(time.Second)
}
}
}
}
func watch(client *etcd.Client, etcdchan chan *etcd.Response, key string, closechan chan bool) {
idx := uint64(0)
for true {
select {
case <-closechan:
log.V(2).Infof("Gracefully closing etcd watch loop: key=%s", key)
return
default:
log.V(2).Infof("Creating etcd watcher: key=%s, index=%d, machines=%s", key, idx, strings.Join(client.GetCluster(), ","))
resp, err := client.Watch(key, idx, true, nil, nil)
if err == nil {
idx = resp.Node.ModifiedIndex + 1
etcdchan <- resp
} else {
log.V(2).Infof("etcd watcher returned error: key=%s, err=\"%s\"", key, err.Error())
// Let's not slam the etcd server in the event that we know
// an unexpected error occurred.
time.Sleep(time.Second)
}
}
}
}
