// apply takes entries received from Raft (after it has been committed) and
// applies them to the current state of the EtcdServer.
// The given entries should not be empty.
func (s *EtcdServer) apply(es []raftpb.Entry, confState *raftpb.ConfState) (uint64, bool) {
var applied uint64
var shouldstop bool
var err error
for i := range es {
e := es[i]
switch e.Type {
case raftpb.EntryNormal:
var r pb.Request
pbutil.MustUnmarshal(&r, e.Data)
s.w.Trigger(r.ID, s.applyRequest(r))
case raftpb.EntryConfChange:
var cc raftpb.ConfChange
pbutil.MustUnmarshal(&cc, e.Data)
shouldstop, err = s.applyConfChange(cc, confState)
s.w.Trigger(cc.ID, err)
default:
log.Panicf("entry type should be either EntryNormal or EntryConfChange")
}
atomic.StoreUint64(&s.r.index, e.Index)
atomic.StoreUint64(&s.r.term, e.Term)
applied = e.Index
}
return applied, shouldstop
}
// getIDs returns an ordered set of IDs included in the given snapshot and
// the entries. The given snapshot/entries can contain two kinds of
// ID-related entry:
// - ConfChangeAddNode, in which case the contained ID will be added into the set.
// - ConfChangeAddRemove, in which case the contained ID will be removed from the set.
func getIDs(snap *raftpb.Snapshot, ents []raftpb.Entry) []uint64 {
ids := make(map[uint64]bool)
if snap != nil {
for _, id := range snap.Metadata.ConfState.Nodes {
ids[id] = true
}
}
for _, e := range ents {
if e.Type != raftpb.EntryConfChange {
continue
}
var cc raftpb.ConfChange
pbutil.MustUnmarshal(&cc, e.Data)
switch cc.Type {
case raftpb.ConfChangeAddNode:
ids[cc.NodeID] = true
case raftpb.ConfChangeRemoveNode:
delete(ids, cc.NodeID)
default:
log.Panicf("ConfChange Type should be either ConfChangeAddNode or ConfChangeRemoveNode!")
}
}
sids := make(types.Uint64Slice, 0)
for id := range ids {
sids = append(sids, id)
}
sort.Sort(sids)
return []uint64(sids)
}
func readWAL(waldir string, snap walpb.Snapshot) (w *wal.WAL, id, cid types.ID, st raftpb.HardState, ents []raftpb.Entry) {
var err error
if w, err = wal.Open(waldir, snap); err != nil {
log.Fatalf("etcdserver: open wal error: %v", err)
}
var wmetadata []byte
if wmetadata, st, ents, err = w.ReadAll(); err != nil {
log.Fatalf("etcdserver: read wal error: %v", err)
}
var metadata pb.Metadata
pbutil.MustUnmarshal(&metadata, wmetadata)
id = types.ID(metadata.NodeID)
cid = types.ID(metadata.ClusterID)
return
}