refactor: move raft transport initialization closer to cluster setup

Author: Carpe-Wang

server/etcdserver/bootstrap.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	stats "go.etcd.io/etcd/server/v3/etcdserver/api/v2stats"
 	"io"
 	"net/http"
 	"os"
@@ -104,24 +105,54 @@ func bootstrap(cfg config.ServerConfig) (b *bootstrappedServer, err error) {
 		backend.Close()
 		return nil, err
 	}
+	sstats := stats.NewServerStats(cfg.Name, cluster.cl.String())
+	lstats := stats.NewLeaderStats(cfg.Logger, cluster.nodeID.String())
+
+	raftTransport := &rafthttp.Transport{
+		Logger:      cfg.Logger,
+		TLSInfo:     cfg.PeerTLSInfo,
+		DialTimeout: cfg.PeerDialTimeout(),
+		ID:          cluster.nodeID,
+		URLs:        cfg.PeerURLs,
+		ClusterID:   cluster.cl.ID(),
+		ServerStats: sstats,
+		LeaderStats: lstats,
+		ErrorC:      make(chan error, 1), // placeholder, can override later
+	}
+	if err = raftTransport.Start(); err != nil {
+		return nil, err
+	}
+	for _, m := range cluster.remotes {
+		if m.ID != cluster.nodeID {
+			raftTransport.AddRemote(m.ID, m.PeerURLs)
+		}
+	}
+	for _, m := range cluster.cl.Members() {
+		if m.ID != cluster.nodeID {
+			raftTransport.AddPeer(m.ID, m.PeerURLs)
+		}
+	}
 
 	cfg.Logger.Info("bootstrapping raft")
 	raft := bootstrapRaft(cfg, cluster, s.wal)
+
 	return &bootstrappedServer{
-		prt:     prt,
-		ss:      ss,
-		storage: s,
-		cluster: cluster,
-		raft:    raft,
+		prt:           prt,
+		ss:            ss,
+		storage:       s,
+		cluster:       cluster,
+		raft:          raft,
+		raftTransport: raftTransport,
 	}, nil
 }
 
 type bootstrappedServer struct {
-	storage *bootstrappedStorage
-	cluster *bootstrappedCluster
-	raft    *bootstrappedRaft
-	prt     http.RoundTripper
-	ss      *snap.Snapshotter
+	storage       *bootstrappedStorage
+	cluster       *bootstrappedCluster
+	raft          *bootstrappedRaft
+	prt           http.RoundTripper
+	ss            *snap.Snapshotter
+	raftTransport *rafthttp.Transport
 }
 
 func (s *bootstrappedServer) Close() {

server/etcdserver/server.go

@@ -418,36 +418,10 @@ func NewServer(cfg config.ServerConfig) (srv *EtcdServer, err error) {
 	// the hook being called during the initialization process.
 	srv.be.SetTxPostLockInsideApplyHook(srv.getTxPostLockInsideApplyHook())
 
-	// TODO: move transport initialization near the definition of remote
-	tr := &rafthttp.Transport{
-		Logger:      cfg.Logger,
-		TLSInfo:     cfg.PeerTLSInfo,
-		DialTimeout: cfg.PeerDialTimeout(),
-		ID:          b.cluster.nodeID,
-		URLs:        cfg.PeerURLs,
-		ClusterID:   b.cluster.cl.ID(),
-		Raft:        srv,
-		Snapshotter: b.ss,
-		ServerStats: sstats,
-		LeaderStats: lstats,
-		ErrorC:      srv.errorc,
-	}
-	if err = tr.Start(); err != nil {
-		return nil, err
-	}
-	// add all remotes into transport
-	for _, m := range b.cluster.remotes {
-		if m.ID != b.cluster.nodeID {
-			tr.AddRemote(m.ID, m.PeerURLs)
-		}
-	}
-	for _, m := range b.cluster.cl.Members() {
-		if m.ID != b.cluster.nodeID {
-			tr.AddPeer(m.ID, m.PeerURLs)
-		}
-	}
+	tr := b.raftTransport
+	tr.Raft = srv
 	srv.r.transport = tr
-
+	tr.ErrorC = srv.errorc
 	return srv, nil
 }