*: lease forwarding should resue transport

etcdserver/server.go

@@ -179,9 +179,10 @@ type EtcdServer struct {
 	// consistent index used to hold the offset of current executing entry
 	// It is initialized to 0 before executing any entry.
 	consistIndex consistentIndex
-	// versionRt used to send requests for peer version
-	versionRt http.RoundTripper
-	reqIDGen  *idutil.Generator
+
+	// peerRt used to send requests (version, lease) to peers.
+	peerRt   http.RoundTripper
+	reqIDGen *idutil.Generator
 
 	// forceVersionC is used to force the version monitor loop
 	// to detect the cluster version immediately.
@@ -353,7 +354,7 @@ func NewServer(cfg *ServerConfig) (*EtcdServer, error) {
 		stats:         sstats,
 		lstats:        lstats,
 		SyncTicker:    time.Tick(500 * time.Millisecond),
-		versionRt:     prt,
+		peerRt:        prt,
 		reqIDGen:      idutil.NewGenerator(uint8(id), time.Now()),
 		forceVersionC: make(chan struct{}),
 		msgSnapC:      make(chan raftpb.Message, maxInFlightMsgSnap),
@@ -1223,7 +1224,7 @@ func (s *EtcdServer) monitorVersions() {
 			continue
 		}
 
-		v := decideClusterVersion(getVersions(s.cluster, s.id, s.versionRt))
+		v := decideClusterVersion(getVersions(s.cluster, s.id, s.peerRt))
 		if v != nil {
 			// only keep major.minor version for comparison
 			v = &semver.Version{

etcdserver/v3demo_server.go

@@ -140,7 +140,7 @@ func (s *EtcdServer) LeaseRenew(id lease.LeaseID) (int64, error) {
 
 	for _, url := range leader.PeerURLs {
 		lurl := url + "/leases"
-		ttl, err = leasehttp.RenewHTTP(id, lurl, s.cfg.PeerTLSInfo, s.cfg.peerDialTimeout())
+		ttl, err = leasehttp.RenewHTTP(id, lurl, s.peerRt, s.cfg.peerDialTimeout())
 		if err == nil {
 			break
 		}

lease/leasehttp/http.go

@@ -23,7 +23,6 @@ import (
 
 	pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
 	"github.com/coreos/etcd/lease"
-	"github.com/coreos/etcd/pkg/transport"
 )
 
 // NewHandler returns an http Handler for lease renewals
@@ -70,20 +69,14 @@ func (h *leaseHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 // RenewHTTP renews a lease at a given primary server.
-func RenewHTTP(id lease.LeaseID, url string, tlsInfo transport.TLSInfo, timeout time.Duration) (int64, error) {
+// TODO: Batch request in future?
+func RenewHTTP(id lease.LeaseID, url string, rt http.RoundTripper, timeout time.Duration) (int64, error) {
 	// will post lreq protobuf to leader
 	lreq, err := (&pb.LeaseKeepAliveRequest{ID: int64(id)}).Marshal()
 	if err != nil {
 		return -1, err
 	}
 
-	// TODO creating a new transporter for each forward request
-	// can be expensive; in the future reuse transports and batch requests
-	rt, err := transport.NewTimeoutTransport(tlsInfo, timeout, 0, 0)
-	if err != nil {
-		return -1, err
-	}
-
 	cc := &http.Client{Transport: rt, Timeout: timeout}
 	resp, err := cc.Post(url, "application/protobuf", bytes.NewReader(lreq))
 	if err != nil {