// start prepares and starts raftNode in a new goroutine. It is no longer safe
// to modify the fields after it has been started.
// TODO: Ideally raftNode should get rid of the passed in server structure.
func (r *raftNode) start(s *EtcdServer) {
r.s = s
r.raftStorage.raftStarted = true
r.applyc = make(chan apply)
r.stopped = make(chan struct{})
r.done = make(chan struct{})
go func() {
var syncC <-chan time.Time
defer r.onStop()
for {
select {
case <-r.ticker:
r.Tick()
case rd := <-r.Ready():
if rd.SoftState != nil {
if lead := atomic.LoadUint64(&r.lead); rd.SoftState.Lead != raft.None && lead != rd.SoftState.Lead {
r.mu.Lock()
r.lt = time.Now()
r.mu.Unlock()
}
atomic.StoreUint64(&r.lead, rd.SoftState.Lead)
if rd.RaftState == raft.StateLeader {
syncC = r.s.SyncTicker
// TODO: remove the nil checking
// current test utility does not provide the stats
if r.s.stats != nil {
r.s.stats.BecomeLeader()
}
} else {
syncC = nil
}
}
apply := apply{
entries: rd.CommittedEntries,
snapshot: rd.Snapshot,
done: make(chan struct{}),
}
select {
case r.applyc <- apply:
case <-r.stopped:
return
}
if !raft.IsEmptySnap(rd.Snapshot) {
if err := r.storage.SaveSnap(rd.Snapshot); err != nil {
plog.Fatalf("raft save snapshot error: %v", err)
}
r.raftStorage.ApplySnapshot(rd.Snapshot)
plog.Infof("raft applied incoming snapshot at index %d", rd.Snapshot.Metadata.Index)
}
if err := r.storage.Save(rd.HardState, rd.Entries); err != nil {
plog.Fatalf("raft save state and entries error: %v", err)
}
r.raftStorage.Append(rd.Entries)
r.s.send(rd.Messages)
select {
case <-apply.done:
case <-r.stopped:
return
}
r.Advance()
case <-syncC:
r.s.sync(r.s.cfg.ReqTimeout())
case <-r.stopped:
return
}
}
}()
}
func (s *Snapshotter) SaveSnap(snapshot raftpb.Snapshot) error {
if raft.IsEmptySnap(snapshot) {
return nil
}
return s.save(&snapshot)
}