Intermediate commit.

.gitignore

@@ -1,5 +1,5 @@
 src/
 pkg/
 /etcd
-release_version.go
+/server/release_version.go
 /machine*

build

@@ -21,5 +21,5 @@ for i in third_party/*; do
 	cp -R "$i" src/
 done
 
-./scripts/release-version > release_version.go
+./scripts/release-version > server/release_version.go
 go build "${ETCD_PACKAGE}"

build.ps1

@@ -20,5 +20,5 @@ foreach($i in (ls third_party/*)){
 	cp -Recurse -force "$i" src/
 }
 
-./scripts/release-version.ps1 | Out-File -Encoding UTF8 release_version.go
+./scripts/release-version.ps1 | Out-File -Encoding UTF8 server/release_version.go
 go build -v "${ETCD_PACKAGE}"

command/command.go

@@ -1,19 +0,0 @@
-package command
-
-import (
-	"github.com/coreos/go-raft"
-)
-
-// A command represents an action to be taken on the replicated state machine.
-type Command interface {
-	CommandName() string
-	Apply(server *raft.Server) (interface{}, error)
-}
-
-// Registers commands to the Raft library.
-func Register() {
-	raft.RegisterCommand(&DeleteCommand{})
-	raft.RegisterCommand(&TestAndSetCommand{})
-	raft.RegisterCommand(&CreateCommand{})
-	raft.RegisterCommand(&UpdateCommand{})
-}

etcd.go

@@ -85,12 +85,6 @@ func init() {
 	flag.StringVar(&cors, "cors", "", "whitelist origins for cross-origin resource sharing (e.g. '*' or 'http://localhost:8001,etc')")
 }
 
-const (
-	ElectionTimeout  = 200 * time.Millisecond
-	HeartbeatTimeout = 50 * time.Millisecond
-	RetryInterval    = 10
-)
-
 //------------------------------------------------------------------------------
 //
 // Typedefs
@@ -185,16 +179,18 @@ func main() {
 	// Create etcd key-value store
 	etcdStore = store.New()
 
-	// Create etcd and raft server
-	r := newRaftServer(info.Name, info.RaftURL, info.RaftListenHost, &raftTLSConfig, &info.RaftTLS)
-	r.MaxClusterSize = maxClusterSize
-	snapConf = r.newSnapshotConf()
+	// Create a shared node registry.
+	registry := server.NewRegistry()
+
+	// Create peer server.
+	ps := NewPeerServer(info.Name, dirPath, info.RaftURL, info.RaftListenHost, &raftTLSConfig, &info.RaftTLS, registry)
+	ps.MaxClusterSize = maxClusterSize
 
 	s := server.New(info.Name, info.EtcdURL, info.EtcdListenHost, &etcdTLSConfig, &info.EtcdTLS, r)
 	if err := e.AllowOrigins(cors); err != nil {
 		panic(err)
 	}
 
-	r.ListenAndServe()
+	ps.ListenAndServe(snapshot)
 	s.ListenAndServe()
 }

name_url_map.go

@@ -1,74 +0,0 @@
-package main
-
-import (
-	"net/url"
-	"path"
-)
-
-// we map node name to url
-type nodeInfo struct {
-	raftVersion string
-	raftURL     string
-	etcdURL     string
-}
-
-var namesMap = make(map[string]*nodeInfo)
-
-// nameToEtcdURL maps node name to its etcd http address
-func nameToEtcdURL(name string) (string, bool) {
-
-	if info, ok := namesMap[name]; ok {
-		// first try to read from the map
-		return info.etcdURL, true
-	}
-
-	// if fails, try to recover from etcd storage
-	return readURL(name, "etcd")
-
-}
-
-// nameToRaftURL maps node name to its raft http address
-func nameToRaftURL(name string) (string, bool) {
-	if info, ok := namesMap[name]; ok {
-		// first try to read from the map
-		return info.raftURL, true
-
-	}
-
-	// if fails, try to recover from etcd storage
-	return readURL(name, "raft")
-}
-
-// addNameToURL add a name that maps to raftURL and etcdURL
-func addNameToURL(name string, version string, raftURL string, etcdURL string) {
-	namesMap[name] = &nodeInfo{
-		raftVersion: raftVersion,
-		raftURL:     raftURL,
-		etcdURL:     etcdURL,
-	}
-}
-
-func readURL(nodeName string, urlName string) (string, bool) {
-	if nodeName == "" {
-		return "", false
-	}
-
-	// convert nodeName to url from etcd storage
-	key := path.Join("/_etcd/machines", nodeName)
-
-	e, err := etcdStore.Get(key, false, false, 0, 0)
-
-	if err != nil {
-		return "", false
-	}
-
-	m, err := url.ParseQuery(e.Value)
-
-	if err != nil {
-		panic("Failed to parse machines entry")
-	}
-
-	url := m[urlName][0]
-
-	return url, true
-}

raft_handlers.go

@@ -1,147 +0,0 @@
-package main
-
-import (
-	"encoding/json"
-	"net/http"
-
-	"github.com/coreos/go-raft"
-)
-
-//-------------------------------------------------------------
-// Handlers to handle raft related request via raft server port
-//-------------------------------------------------------------
-
-// Get all the current logs
-func (r *raftServer) GetLogHttpHandler(w http.ResponseWriter, req *http.Request) {
-	debugf("[recv] GET %s/log", r.url)
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(http.StatusOK)
-	json.NewEncoder(w).Encode(r.LogEntries())
-}
-
-// Response to vote request
-func (r *raftServer) VoteHttpHandler(w http.ResponseWriter, req *http.Request) {
-	rvreq := &raft.RequestVoteRequest{}
-	err := decodeJsonRequest(req, rvreq)
-	if err == nil {
-		debugf("[recv] POST %s/vote [%s]", r.url, rvreq.CandidateName)
-		if resp := r.RequestVote(rvreq); resp != nil {
-			w.WriteHeader(http.StatusOK)
-			json.NewEncoder(w).Encode(resp)
-			return
-		}
-	}
-	warnf("[vote] ERROR: %v", err)
-	w.WriteHeader(http.StatusInternalServerError)
-}
-
-// Response to append entries request
-func (r *raftServer) AppendEntriesHttpHandler(w http.ResponseWriter, req *http.Request) {
-	aereq := &raft.AppendEntriesRequest{}
-	err := decodeJsonRequest(req, aereq)
-
-	if err == nil {
-		debugf("[recv] POST %s/log/append [%d]", r.url, len(aereq.Entries))
-
-		r.serverStats.RecvAppendReq(aereq.LeaderName, int(req.ContentLength))
-
-		if resp := r.AppendEntries(aereq); resp != nil {
-			w.WriteHeader(http.StatusOK)
-			json.NewEncoder(w).Encode(resp)
-			if !resp.Success {
-				debugf("[Append Entry] Step back")
-			}
-			return
-		}
-	}
-	warnf("[Append Entry] ERROR: %v", err)
-	w.WriteHeader(http.StatusInternalServerError)
-}
-
-// Response to recover from snapshot request
-func (r *raftServer) SnapshotHttpHandler(w http.ResponseWriter, req *http.Request) {
-	aereq := &raft.SnapshotRequest{}
-	err := decodeJsonRequest(req, aereq)
-	if err == nil {
-		debugf("[recv] POST %s/snapshot/ ", r.url)
-		if resp := r.RequestSnapshot(aereq); resp != nil {
-			w.WriteHeader(http.StatusOK)
-			json.NewEncoder(w).Encode(resp)
-			return
-		}
-	}
-	warnf("[Snapshot] ERROR: %v", err)
-	w.WriteHeader(http.StatusInternalServerError)
-}
-
-// Response to recover from snapshot request
-func (r *raftServer) SnapshotRecoveryHttpHandler(w http.ResponseWriter, req *http.Request) {
-	aereq := &raft.SnapshotRecoveryRequest{}
-	err := decodeJsonRequest(req, aereq)
-	if err == nil {
-		debugf("[recv] POST %s/snapshotRecovery/ ", r.url)
-		if resp := r.SnapshotRecoveryRequest(aereq); resp != nil {
-			w.WriteHeader(http.StatusOK)
-			json.NewEncoder(w).Encode(resp)
-			return
-		}
-	}
-	warnf("[Snapshot] ERROR: %v", err)
-	w.WriteHeader(http.StatusInternalServerError)
-}
-
-// Get the port that listening for etcd connecting of the server
-func (r *raftServer) EtcdURLHttpHandler(w http.ResponseWriter, req *http.Request) {
-	debugf("[recv] Get %s/etcdURL/ ", r.url)
-	w.WriteHeader(http.StatusOK)
-	w.Write([]byte(argInfo.EtcdURL))
-}
-
-// Response to the join request
-func (r *raftServer) JoinHttpHandler(w http.ResponseWriter, req *http.Request) error {
-
-	command := &JoinCommand{}
-
-	if err := decodeJsonRequest(req, command); err == nil {
-		debugf("Receive Join Request from %s", command.Name)
-		return r.dispatchRaftCommand(command, w, req)
-	} else {
-		w.WriteHeader(http.StatusInternalServerError)
-		return nil
-	}
-}
-
-// Response to remove request
-func (r *raftServer) RemoveHttpHandler(w http.ResponseWriter, req *http.Request) {
-	if req.Method != "DELETE" {
-		w.WriteHeader(http.StatusMethodNotAllowed)
-		return
-	}
-
-	nodeName := req.URL.Path[len("/remove/"):]
-	command := &RemoveCommand{
-		Name: nodeName,
-	}
-
-	debugf("[recv] Remove Request [%s]", command.Name)
-
-	r.dispatchRaftCommand(command, w, req)
-}
-
-// Response to the name request
-func (r *raftServer) NameHttpHandler(w http.ResponseWriter, req *http.Request) {
-	debugf("[recv] Get %s/name/ ", r.url)
-	w.WriteHeader(http.StatusOK)
-	w.Write([]byte(r.name))
-}
-
-// Response to the name request
-func (r *raftServer) RaftVersionHttpHandler(w http.ResponseWriter, req *http.Request) {
-	debugf("[recv] Get %s/version/ ", r.url)
-	w.WriteHeader(http.StatusOK)
-	w.Write([]byte(r.version))
-}
-
-func (r *raftServer) dispatchRaftCommand(c Command, w http.ResponseWriter, req *http.Request) error {
-	return r.dispatch(c, w, req, nameToRaftURL)
-}

raft_server.go

@@ -1,317 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"crypto/tls"
-	"encoding/binary"
-	"encoding/json"
-	"fmt"
-	"io/ioutil"
-	"net/http"
-	"net/url"
-	"time"
-
-	"github.com/coreos/etcd/command"
-	etcdErr "github.com/coreos/etcd/error"
-	"github.com/coreos/go-raft"
-)
-
-func init() {
-	command.Register()
-}
-
-type raftServer struct {
-	*raft.Server
-	version        string
-	joinIndex      uint64
-	name           string
-	url            string
-	listenHost     string
-	tlsConf        *TLSConfig
-	tlsInfo        *TLSInfo
-	followersStats *raftFollowersStats
-	serverStats    *raftServerStats
-	MaxClusterSize int
-}
-
-func newRaftServer(name string, url string, listenHost string, tlsConf *TLSConfig, tlsInfo *TLSInfo) *raftServer {
-
-	raftWrapper := &raftServer{
-		version:    raftVersion,
-		name:       name,
-		url:        url,
-		listenHost: listenHost,
-		tlsConf:    tlsConf,
-		tlsInfo:    tlsInfo,
-		followersStats: &raftFollowersStats{
-			Leader:    name,
-			Followers: make(map[string]*raftFollowerStats),
-		},
-		serverStats: &raftServerStats{
-			StartTime: time.Now(),
-			sendRateQueue: &statsQueue{
-				back: -1,
-			},
-			recvRateQueue: &statsQueue{
-				back: -1,
-			},
-		},
-	}
-
-	// Create transporter for raft
-	raftTransporter := newTransporter(tlsConf.Scheme, tlsConf.Client, raftWrapper)
-
-	// Create raft server
-	server, err := raft.NewServer(name, dirPath, raftTransporter, etcdStore, raftWrapper, "")
-	check(err)
-
-	raftWrapper.Server = server
-
-	return raftWrapper
-}
-
-// Start the raft server
-func (r *raftServer) ListenAndServe() {
-	// LoadSnapshot
-	if snapshot {
-		err := r.LoadSnapshot()
-
-		if err == nil {
-			debugf("%s finished load snapshot", r.name)
-		} else {
-			debug(err)
-		}
-	}
-
-	r.SetElectionTimeout(ElectionTimeout)
-	r.SetHeartbeatTimeout(HeartbeatTimeout)
-
-	r.Start()
-
-	if r.IsLogEmpty() {
-
-		// start as a leader in a new cluster
-		if len(cluster) == 0 {
-			r.startAsLeader()
-
-		} else {
-			r.startAsFollower()
-		}
-
-	} else {
-
-		// rejoin the previous cluster
-		cluster = r.getMachines(nameToRaftURL)
-		for i := 0; i < len(cluster); i++ {
-			u, err := url.Parse(cluster[i])
-			if err != nil {
-				debug("rejoin cannot parse url: ", err)
-			}
-			cluster[i] = u.Host
-		}
-		ok := r.joinCluster(cluster)
-		if !ok {
-			warn("the entire cluster is down! this machine will restart the cluster.")
-		}
-
-		debugf("%s restart as a follower", r.name)
-	}
-
-	// open the snapshot
-	if snapshot {
-		go r.monitorSnapshot()
-	}
-
-	// start to response to raft requests
-	go r.startTransport(r.tlsConf.Scheme, r.tlsConf.Server)
-
-}
-
-func (r *raftServer) startAsLeader() {
-	// leader need to join self as a peer
-	for {
-		_, err := r.Do(newJoinCommand(r.version, r.Name(), r.url, e.url))
-		if err == nil {
-			break
-		}
-	}
-	debugf("%s start as a leader", r.name)
-}
-
-func (r *raftServer) startAsFollower() {
-	// start as a follower in a existing cluster
-	for i := 0; i < retryTimes; i++ {
-		ok := r.joinCluster(cluster)
-		if ok {
-			return
-		}
-		warnf("cannot join to cluster via given machines, retry in %d seconds", RetryInterval)
-		time.Sleep(time.Second * RetryInterval)
-	}
-
-	fatalf("Cannot join the cluster via given machines after %x retries", retryTimes)
-}
-
-// Start to listen and response raft command
-func (r *raftServer) startTransport(scheme string, tlsConf tls.Config) {
-	infof("raft server [name %s, listen on %s, advertised url %s]", r.name, r.listenHost, r.url)
-
-	raftMux := http.NewServeMux()
-
-	server := &http.Server{
-		Handler:   raftMux,
-		TLSConfig: &tlsConf,
-		Addr:      r.listenHost,
-	}
-
-	// internal commands
-	raftMux.HandleFunc("/name", r.NameHttpHandler)
-	raftMux.HandleFunc("/version", r.RaftVersionHttpHandler)
-	raftMux.Handle("/join", errorHandler(r.JoinHttpHandler))
-	raftMux.HandleFunc("/remove/", r.RemoveHttpHandler)
-	raftMux.HandleFunc("/vote", r.VoteHttpHandler)
-	raftMux.HandleFunc("/log", r.GetLogHttpHandler)
-	raftMux.HandleFunc("/log/append", r.AppendEntriesHttpHandler)
-	raftMux.HandleFunc("/snapshot", r.SnapshotHttpHandler)
-	raftMux.HandleFunc("/snapshotRecovery", r.SnapshotRecoveryHttpHandler)
-	raftMux.HandleFunc("/etcdURL", r.EtcdURLHttpHandler)
-
-	if scheme == "http" {
-		fatal(server.ListenAndServe())
-	} else {
-		fatal(server.ListenAndServeTLS(r.tlsInfo.CertFile, r.tlsInfo.KeyFile))
-	}
-
-}
-
-// getVersion fetches the raft version of a peer. This works for now but we
-// will need to do something more sophisticated later when we allow mixed
-// version clusters.
-func getVersion(t *transporter, versionURL url.URL) (string, error) {
-	resp, req, err := t.Get(versionURL.String())
-
-	if err != nil {
-		return "", err
-	}
-
-	defer resp.Body.Close()
-
-	t.CancelWhenTimeout(req)
-
-	body, err := ioutil.ReadAll(resp.Body)
-
-	return string(body), nil
-}
-
-func (r *raftServer) joinCluster(cluster []string) bool {
-	for _, machine := range cluster {
-
-		if len(machine) == 0 {
-			continue
-		}
-
-		err := r.joinByMachine(r.Server, machine, r.tlsConf.Scheme)
-		if err == nil {
-			debugf("%s success join to the cluster via machine %s", r.name, machine)
-			return true
-
-		} else {
-			if _, ok := err.(etcdErr.Error); ok {
-				fatal(err)
-			}
-
-			debugf("cannot join to cluster via machine %s %s", machine, err)
-		}
-	}
-	return false
-}
-
-// Send join requests to machine.
-func (r *raftServer) joinByMachine(s *raft.Server, machine string, scheme string) error {
-	var b bytes.Buffer
-
-	// t must be ok
-	t, _ := r.Transporter().(*transporter)
-
-	// Our version must match the leaders version
-	versionURL := url.URL{Host: machine, Scheme: scheme, Path: "/version"}
-	version, err := getVersion(t, versionURL)
-	if err != nil {
-		return fmt.Errorf("Unable to join: %v", err)
-	}
-
-	// TODO: versioning of the internal protocol. See:
-	// Documentation/internatl-protocol-versioning.md
-	if version != r.version {
-		return fmt.Errorf("Unable to join: internal version mismatch, entire cluster must be running identical versions of etcd")
-	}
-
-	json.NewEncoder(&b).Encode(newJoinCommand(r.version, r.Name(), r.url, e.url))
-
-	joinURL := url.URL{Host: machine, Scheme: scheme, Path: "/join"}
-
-	debugf("Send Join Request to %s", joinURL.String())
-
-	resp, req, err := t.Post(joinURL.String(), &b)
-
-	for {
-		if err != nil {
-			return fmt.Errorf("Unable to join: %v", err)
-		}
-		if resp != nil {
-			defer resp.Body.Close()
-
-			t.CancelWhenTimeout(req)
-
-			if resp.StatusCode == http.StatusOK {
-				b, _ := ioutil.ReadAll(resp.Body)
-				r.joinIndex, _ = binary.Uvarint(b)
-				return nil
-			}
-			if resp.StatusCode == http.StatusTemporaryRedirect {
-
-				address := resp.Header.Get("Location")
-				debugf("Send Join Request to %s", address)
-
-				json.NewEncoder(&b).Encode(newJoinCommand(r.version, r.Name(), r.url, e.url))
-
-				resp, req, err = t.Post(address, &b)
-
-			} else if resp.StatusCode == http.StatusBadRequest {
-				debug("Reach max number machines in the cluster")
-				decoder := json.NewDecoder(resp.Body)
-				err := &etcdErr.Error{}
-				decoder.Decode(err)
-				return *err
-			} else {
-				return fmt.Errorf("Unable to join")
-			}
-		}
-
-	}
-	return fmt.Errorf("Unable to join: %v", err)
-}
-
-func (r *raftServer) Stats() []byte {
-	r.serverStats.LeaderInfo.Uptime = time.Now().Sub(r.serverStats.LeaderInfo.startTime).String()
-
-	queue := r.serverStats.sendRateQueue
-
-	r.serverStats.SendingPkgRate, r.serverStats.SendingBandwidthRate = queue.Rate()
-
-	queue = r.serverStats.recvRateQueue
-
-	r.serverStats.RecvingPkgRate, r.serverStats.RecvingBandwidthRate = queue.Rate()
-
-	b, _ := json.Marshal(r.serverStats)
-
-	return b
-}
-
-func (r *raftServer) PeerStats() []byte {
-	if r.State() == raft.Leader {
-		b, _ := json.Marshal(r.followersStats)
-		return b
-	}
-	return nil
-}

server/join_command.go

@@ -2,8 +2,6 @@ package server
 
 import (
 	"encoding/binary"
-	"fmt"
-	"path"
 
 	etcdErr "github.com/coreos/etcd/error"
 	"github.com/coreos/etcd/log"
@@ -42,38 +40,32 @@ func (c *JoinCommand) CommandName() string {
 // Join a server to the cluster
 func (c *JoinCommand) Apply(server *raft.Server) (interface{}, error) {
 	s, _ := server.StateMachine().(*store.Store)
-	r, _ := server.Context().(*RaftServer)
-
-	// check if the join command is from a previous machine, who lost all its previous log.
-	e, _ := s.Get(path.Join("/_etcd/machines", c.Name), false, false, server.CommitIndex(), server.Term())
+	ps, _ := server.Context().(*PeerServer)
 
 	b := make([]byte, 8)
 	binary.PutUvarint(b, server.CommitIndex())
 
-	if e != nil {
+	// Check if the join command is from a previous machine, who lost all its previous log.
+	if _, ok := ps.registry.URL(c.Name); ok {
 		return b, nil
 	}
 
-	// check machine number in the cluster
-	if s.MachineCount() == c.MaxClusterSize {
+	// Check machine number in the cluster
+	if ps.registry.Count() == c.MaxClusterSize {
 		log.Debug("Reject join request from ", c.Name)
 		return []byte{0}, etcdErr.NewError(etcdErr.EcodeNoMoreMachine, "", server.CommitIndex(), server.Term())
 	}
 
-	addNameToURL(c.Name, c.RaftVersion, c.RaftURL, c.EtcdURL)
+	// Add to shared machine registry.
+	ps.registry.Register(c.Name, c.RaftVersion, c.RaftURL, c.EtcdURL, server.CommitIndex(), server.Term())
 
-	// add peer in raft
+	// Add peer in raft
 	err := server.AddPeer(c.Name, "")
 
-	// add machine in etcd storage
-	key := path.Join("_etcd/machines", c.Name)
-	value := fmt.Sprintf("raft=%s&etcd=%s&raftVersion=%s", c.RaftURL, c.EtcdURL, c.RaftVersion)
-	s.Create(key, value, false, false, store.Permanent, server.CommitIndex(), server.Term())
-
-	// add peer stats
-	if c.Name != r.Name() {
-		r.followersStats.Followers[c.Name] = &raftFollowerStats{}
-		r.followersStats.Followers[c.Name].Latency.Minimum = 1 << 63
+	// Add peer stats
+	if c.Name != ps.Name() {
+		ps.followersStats.Followers[c.Name] = &raftFollowerStats{}
+		ps.followersStats.Followers[c.Name].Latency.Minimum = 1 << 63
 	}
 
 	return b, err

server/peer_server.go

@@ -0,0 +1,474 @@
+package server
+
+import (
+    "bytes"
+    "crypto/tls"
+    "encoding/binary"
+    "encoding/json"
+    "fmt"
+    "io/ioutil"
+    "net/http"
+    "net/url"
+    "time"
+
+    etcdErr "github.com/coreos/etcd/error"
+    "github.com/coreos/etcd/log"
+    "github.com/coreos/etcd/store"
+    "github.com/coreos/go-raft"
+)
+
+type PeerServer struct {
+    *raft.Server
+    joinIndex      uint64
+    name           string
+    url            string
+    listenHost     string
+    tlsConf        *TLSConfig
+    tlsInfo        *TLSInfo
+    followersStats *raftFollowersStats
+    serverStats    *raftServerStats
+    registry       *Registry
+    store          *store.Store
+    snapConf       *snapshotConf
+    MaxClusterSize int
+}
+
+// TODO: find a good policy to do snapshot
+type snapshotConf struct {
+    // Etcd will check if snapshot is need every checkingInterval
+    checkingInterval time.Duration
+
+    // The number of writes when the last snapshot happened
+    lastWrites uint64
+
+    // If the incremental number of writes since the last snapshot
+    // exceeds the write Threshold, etcd will do a snapshot
+    writesThr uint64
+}
+
+
+func NewPeerServer(name string, path string, url string, listenHost string, tlsConf *TLSConfig, tlsInfo *TLSInfo, registry *Registry, store *store.Store) *PeerServer {
+    s := &PeerServer{
+        name:       name,
+        url:        url,
+        listenHost: listenHost,
+        tlsConf:    tlsConf,
+        tlsInfo:    tlsInfo,
+        registry:   registry,
+        store:      store,
+        snapConf:   &snapshotConf{time.Second * 3, 0, 20 * 1000},
+        followersStats: &raftFollowersStats{
+            Leader:    name,
+            Followers: make(map[string]*raftFollowerStats),
+        },
+        serverStats: &raftServerStats{
+            StartTime: time.Now(),
+            sendRateQueue: &statsQueue{
+                back: -1,
+            },
+            recvRateQueue: &statsQueue{
+                back: -1,
+            },
+        },
+    }
+
+    // Create transporter for raft
+    raftTransporter := newTransporter(tlsConf.Scheme, tlsConf.Client, s)
+
+    // Create raft server
+    server, err := raft.NewServer(name, path, raftTransporter, s.store, s, "")
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    s.Server = server
+
+    return s
+}
+
+// Start the raft server
+func (s *PeerServer) ListenAndServe(snapshot bool, cluster []string) {
+    // LoadSnapshot
+    if snapshot {
+        err := s.LoadSnapshot()
+
+        if err == nil {
+            log.Debugf("%s finished load snapshot", s.name)
+        } else {
+            log.Debug(err)
+        }
+    }
+
+    s.SetElectionTimeout(ElectionTimeout)
+    s.SetHeartbeatTimeout(HeartbeatTimeout)
+
+    s.Start()
+
+    if s.IsLogEmpty() {
+        // start as a leader in a new cluster
+        if len(cluster) == 0 {
+            s.startAsLeader()
+        } else {
+            s.startAsFollower(cluster)
+        }
+
+    } else {
+        // Rejoin the previous cluster
+        cluster = s.registry.PeerURLs()
+        for i := 0; i < len(cluster); i++ {
+            u, err := url.Parse(cluster[i])
+            if err != nil {
+                log.Debug("rejoin cannot parse url: ", err)
+            }
+            cluster[i] = u.Host
+        }
+        ok := s.joinCluster(cluster)
+        if !ok {
+            log.Warn("the entire cluster is down! this machine will restart the cluster.")
+        }
+
+        log.Debugf("%s restart as a follower", s.name)
+    }
+
+    // open the snapshot
+    if snapshot {
+        go s.monitorSnapshot()
+    }
+
+    // start to response to raft requests
+    go s.startTransport(s.tlsConf.Scheme, s.tlsConf.Server)
+
+}
+
+// Get all the current logs
+func (s *PeerServer) GetLogHttpHandler(w http.ResponseWriter, req *http.Request) {
+    log.Debugf("[recv] GET %s/log", s.url)
+    w.Header().Set("Content-Type", "application/json")
+    w.WriteHeader(http.StatusOK)
+    json.NewEncoder(w).Encode(s.LogEntries())
+}
+
+// Response to vote request
+func (s *PeerServer) VoteHttpHandler(w http.ResponseWriter, req *http.Request) {
+    rvreq := &raft.RequestVoteRequest{}
+    err := decodeJsonRequest(req, rvreq)
+    if err == nil {
+        log.Debugf("[recv] POST %s/vote [%s]", s.url, rvreq.CandidateName)
+        if resp := s.RequestVote(rvreq); resp != nil {
+            w.WriteHeader(http.StatusOK)
+            json.NewEncoder(w).Encode(resp)
+            return
+        }
+    }
+    log.Warnf("[vote] ERROR: %v", err)
+    w.WriteHeader(http.StatusInternalServerError)
+}
+
+// Response to append entries request
+func (s *PeerServer) AppendEntriesHttpHandler(w http.ResponseWriter, req *http.Request) {
+    aereq := &raft.AppendEntriesRequest{}
+    err := decodeJsonRequest(req, aereq)
+
+    if err == nil {
+        log.Debugf("[recv] POST %s/log/append [%d]", s.url, len(aereq.Entries))
+
+        s.serverStats.RecvAppendReq(aereq.LeaderName, int(req.ContentLength))
+
+        if resp := s.AppendEntries(aereq); resp != nil {
+            w.WriteHeader(http.StatusOK)
+            json.NewEncoder(w).Encode(resp)
+            if !resp.Success {
+                log.Debugf("[Append Entry] Step back")
+            }
+            return
+        }
+    }
+    log.Warnf("[Append Entry] ERROR: %v", err)
+    w.WriteHeader(http.StatusInternalServerError)
+}
+
+// Response to recover from snapshot request
+func (s *PeerServer) SnapshotHttpHandler(w http.ResponseWriter, req *http.Request) {
+    aereq := &raft.SnapshotRequest{}
+    err := decodeJsonRequest(req, aereq)
+    if err == nil {
+        log.Debugf("[recv] POST %s/snapshot/ ", s.url)
+        if resp := s.RequestSnapshot(aereq); resp != nil {
+            w.WriteHeader(http.StatusOK)
+            json.NewEncoder(w).Encode(resp)
+            return
+        }
+    }
+    log.Warnf("[Snapshot] ERROR: %v", err)
+    w.WriteHeader(http.StatusInternalServerError)
+}
+
+// Response to recover from snapshot request
+func (s *PeerServer) SnapshotRecoveryHttpHandler(w http.ResponseWriter, req *http.Request) {
+    aereq := &raft.SnapshotRecoveryRequest{}
+    err := decodeJsonRequest(req, aereq)
+    if err == nil {
+        log.Debugf("[recv] POST %s/snapshotRecovery/ ", s.url)
+        if resp := s.SnapshotRecoveryRequest(aereq); resp != nil {
+            w.WriteHeader(http.StatusOK)
+            json.NewEncoder(w).Encode(resp)
+            return
+        }
+    }
+    log.Warnf("[Snapshot] ERROR: %v", err)
+    w.WriteHeader(http.StatusInternalServerError)
+}
+
+// Get the port that listening for etcd connecting of the server
+func (s *PeerServer) EtcdURLHttpHandler(w http.ResponseWriter, req *http.Request) {
+    log.Debugf("[recv] Get %s/etcdURL/ ", s.url)
+    w.WriteHeader(http.StatusOK)
+    w.Write([]byte(argInfo.EtcdURL))
+}
+
+// Response to the join request
+func (s *PeerServer) JoinHttpHandler(w http.ResponseWriter, req *http.Request) error {
+    command := &JoinCommand{}
+
+    if err := decodeJsonRequest(req, command); err == nil {
+        log.Debugf("Receive Join Request from %s", command.Name)
+        return s.dispatchRaftCommand(command, w, req)
+    } else {
+        w.WriteHeader(http.StatusInternalServerError)
+        return nil
+    }
+}
+
+// Response to remove request
+func (s *PeerServer) RemoveHttpHandler(w http.ResponseWriter, req *http.Request) {
+    if req.Method != "DELETE" {
+        w.WriteHeader(http.StatusMethodNotAllowed)
+        return
+    }
+
+    nodeName := req.URL.Path[len("/remove/"):]
+    command := &RemoveCommand{
+        Name: nodeName,
+    }
+
+    log.Debugf("[recv] Remove Request [%s]", command.Name)
+
+    s.dispatchRaftCommand(command, w, req)
+}
+
+// Response to the name request
+func (s *PeerServer) NameHttpHandler(w http.ResponseWriter, req *http.Request) {
+    log.Debugf("[recv] Get %s/name/ ", s.url)
+    w.WriteHeader(http.StatusOK)
+    w.Write([]byte(s.name))
+}
+
+// Response to the name request
+func (s *PeerServer) RaftVersionHttpHandler(w http.ResponseWriter, req *http.Request) {
+    log.Debugf("[recv] Get %s/version/ ", s.url)
+    w.WriteHeader(http.StatusOK)
+    w.Write([]byte(PeerVersion))
+}
+
+func (s *PeerServer) dispatchRaftCommand(c raft.Command, w http.ResponseWriter, req *http.Request) error {
+    return s.dispatch(c, w, req, nameToRaftURL)
+}
+
+func (s *PeerServer) startAsLeader() {
+    // leader need to join self as a peer
+    for {
+        _, err := s.Do(newJoinCommand(PeerVersion, s.Name(), s.url, e.url))
+        if err == nil {
+            break
+        }
+    }
+    log.Debugf("%s start as a leader", s.name)
+}
+
+func (s *PeerServer) startAsFollower(cluster []string) {
+    // start as a follower in a existing cluster
+    for i := 0; i < retryTimes; i++ {
+        ok := s.joinCluster(cluster)
+        if ok {
+            return
+        }
+        log.Warnf("cannot join to cluster via given machines, retry in %d seconds", RetryInterval)
+        time.Sleep(time.Second * RetryInterval)
+    }
+
+    fatalf("Cannot join the cluster via given machines after %x retries", retryTimes)
+}
+
+// Start to listen and response raft command
+func (s *PeerServer) startTransport(scheme string, tlsConf tls.Config) {
+    infof("raft server [name %s, listen on %s, advertised url %s]", s.name, s.listenHost, s.url)
+
+    raftMux := http.NewServeMux()
+
+    server := &http.Server{
+        Handler:   raftMux,
+        TLSConfig: &tlsConf,
+        Addr:      s.listenHost,
+    }
+
+    // internal commands
+    raftMux.HandleFunc("/name", s.NameHttpHandler)
+    raftMux.HandleFunc("/version", s.RaftVersionHttpHandler)
+    raftMux.Handle("/join", errorHandler(s.JoinHttpHandler))
+    raftMux.HandleFunc("/remove/", s.RemoveHttpHandler)
+    raftMux.HandleFunc("/vote", s.VoteHttpHandler)
+    raftMux.HandleFunc("/log", s.GetLogHttpHandler)
+    raftMux.HandleFunc("/log/append", s.AppendEntriesHttpHandler)
+    raftMux.HandleFunc("/snapshot", s.SnapshotHttpHandler)
+    raftMux.HandleFunc("/snapshotRecovery", s.SnapshotRecoveryHttpHandler)
+    raftMux.HandleFunc("/etcdURL", s.EtcdURLHttpHandler)
+
+    if scheme == "http" {
+        fatal(server.ListenAndServe())
+    } else {
+        fatal(server.ListenAndServeTLS(s.tlsInfo.CertFile, s.tlsInfo.KeyFile))
+    }
+
+}
+
+// getVersion fetches the raft version of a peer. This works for now but we
+// will need to do something more sophisticated later when we allow mixed
+// version clusters.
+func getVersion(t *transporter, versionURL url.URL) (string, error) {
+    resp, req, err := t.Get(versionURL.String())
+
+    if err != nil {
+        return "", err
+    }
+
+    defer resp.Body.Close()
+
+    t.CancelWhenTimeout(req)
+
+    body, err := ioutil.ReadAll(resp.Body)
+
+    return string(body), nil
+}
+
+func (s *PeerServer) joinCluster(cluster []string) bool {
+    for _, machine := range cluster {
+        if len(machine) == 0 {
+            continue
+        }
+
+        err := s.joinByMachine(s.Server, machine, s.tlsConf.Scheme)
+        if err == nil {
+            log.Debugf("%s success join to the cluster via machine %s", s.name, machine)
+            return true
+
+        } else {
+            if _, ok := err.(etcdErr.Error); ok {
+                fatal(err)
+            }
+
+            log.Debugf("cannot join to cluster via machine %s %s", machine, err)
+        }
+    }
+    return false
+}
+
+// Send join requests to machine.
+func (s *PeerServer) joinByMachine(server *raft.Server, machine string, scheme string) error {
+    var b bytes.Buffer
+
+    // t must be ok
+    t, _ := server.Transporter().(*transporter)
+
+    // Our version must match the leaders version
+    versionURL := url.URL{Host: machine, Scheme: scheme, Path: "/version"}
+    version, err := getVersion(t, versionURL)
+    if err != nil {
+        return fmt.Errorf("Unable to join: %v", err)
+    }
+
+    // TODO: versioning of the internal protocol. See:
+    // Documentation/internatl-protocol-versioning.md
+    if version != PeerVersion {
+        return fmt.Errorf("Unable to join: internal version mismatch, entire cluster must be running identical versions of etcd")
+    }
+
+    json.NewEncoder(&b).Encode(newJoinCommand(PeerVersion, server.Name(), server.url, e.url))
+
+    joinURL := url.URL{Host: machine, Scheme: scheme, Path: "/join"}
+
+    log.Debugf("Send Join Request to %s", joinURL.String())
+
+    resp, req, err := t.Post(joinURL.String(), &b)
+
+    for {
+        if err != nil {
+            return fmt.Errorf("Unable to join: %v", err)
+        }
+        if resp != nil {
+            defer resp.Body.Close()
+
+            t.CancelWhenTimeout(req)
+
+            if resp.StatusCode == http.StatusOK {
+                b, _ := ioutil.ReadAll(resp.Body)
+                server.joinIndex, _ = binary.Uvarint(b)
+                return nil
+            }
+            if resp.StatusCode == http.StatusTemporaryRedirect {
+
+                address := resp.Header.Get("Location")
+                log.Debugf("Send Join Request to %s", address)
+
+                json.NewEncoder(&b).Encode(newJoinCommand(PeerVersion, server.Name(), server.url, e.url))
+
+                resp, req, err = t.Post(address, &b)
+
+            } else if resp.StatusCode == http.StatusBadRequest {
+                debug("Reach max number machines in the cluster")
+                decoder := json.NewDecoder(resp.Body)
+                err := &etcdErr.Error{}
+                decoder.Decode(err)
+                return *err
+            } else {
+                return fmt.Errorf("Unable to join")
+            }
+        }
+
+    }
+    return fmt.Errorf("Unable to join: %v", err)
+}
+
+func (s *PeerServer) Stats() []byte {
+    s.serverStats.LeaderInfo.Uptime = time.Now().Sub(s.serverStats.LeaderInfo.startTime).String()
+
+    queue := s.serverStats.sendRateQueue
+
+    s.serverStats.SendingPkgRate, s.serverStats.SendingBandwidthRate = queue.Rate()
+
+    queue = s.serverStats.recvRateQueue
+
+    s.serverStats.RecvingPkgRate, s.serverStats.RecvingBandwidthRate = queue.Rate()
+
+    b, _ := json.Marshal(s.serverStats)
+
+    return b
+}
+
+func (s *PeerServer) PeerStats() []byte {
+    if s.State() == raft.Leader {
+        b, _ := json.Marshal(s.followersStats)
+        return b
+    }
+    return nil
+}
+
+func (s *PeerServer) monitorSnapshot() {
+    for {
+        time.Sleep(s.snapConf.checkingInterval)
+        currentWrites := 0
+        if uint64(currentWrites) > s.snapConf.writesThr {
+            r.TakeSnapshot()
+            s.snapConf.lastWrites = 0
+        }
+    }
+}

server/registry.go

@@ -0,0 +1,167 @@
+package server
+
+import (
+    "sync"
+
+    "github.com/coreos/etcd/store"
+)
+
+// The location of the machine URL data.
+const RegistryKey = "/_etcd/machines"
+
+// The Registry stores URL information for nodes.
+type Registry struct {
+    sync.Mutex
+    store *store.Store
+    nodes map[string]*node
+}
+
+// The internal storage format of the registry.
+type node struct {
+    peerVersion string
+    peerURL     string
+    url     string
+}
+
+// Creates a new Registry.
+func NewRegistry(s *store.Store) *Registry {
+    return &Registry{
+        store: s,
+        nodes: make(map[string]*node),
+    }
+}
+
+// Adds a node to the registry.
+func (r *Registry) Register(name string, peerVersion string, peerURL string, url string, commitIndex uint64, term uint64) {
+    r.Lock()
+    defer r.Unlock()
+
+    // Write data to store.
+    key := path.Join(RegistryKey, name)
+    value := fmt.Sprintf("raft=%s&etcd=%s&raftVersion=%s", peerURL, url, peerVersion)
+    r.store.Create(key, value, false, false, store.Permanent, commitIndex, term)
+}
+
+// Removes a node from the registry.
+func (r *Registry) Unregister(name string, commitIndex uint64, term uint64) error {
+    r.Lock()
+    defer r.Unlock()
+
+    // Remove the key from the store.
+    _, err := s.Delete(path.Join(RegistryKey, name), false, commitIndex, term)
+    return err
+}
+
+// Returns the number of nodes in the cluster.
+func (r *Registry) Count() int {
+    e, err := s.Get(RegistryKey, false, false, 0, 0)
+    if err != nil {
+        return 0
+    }
+    return len(e.KVPairs)
+}
+
+// Retrieves the URL for a given node by name.
+func (r *Registry) URL(name string) (string, bool) {
+    r.Lock()
+    defer r.Unlock()
+    return r.url(name)
+}
+
+func (r *Registry) url(name string) (string, bool) {
+    if r.nodes[name] == nil {
+        r.load(name)
+    }
+
+    if node := r.nodes[name]; node != nil {
+        return node.url, true
+    }
+
+    return "", false
+}
+
+// Retrieves the URLs for all nodes.
+func (r *Registry) URLs() []string {
+    r.Lock()
+    defer r.Unlock()
+
+    // Retrieve a list of all nodes.
+    e, err := s.Get(RegistryKey, false, false, 0, 0)
+    if err != nil {
+        return make([]string, 0)
+    }
+
+    // Lookup the URL for each one.
+    urls := make([]string, 0)
+    for _, pair := range e.KVPairs {
+        urls = append(urls, r.url(pair.Key))
+    }
+
+    return urls
+}
+
+
+// Retrieves the peer URL for a given node by name.
+func (r *Registry) PeerURL(name string) (string, bool) {
+    r.Lock()
+    defer r.Unlock()
+    return r.peerURL(name)
+}
+
+func (r *Registry) peerURL(name string) (string, bool) {
+    if r.nodes[name] == nil {
+        r.load(name)
+    }
+
+    if node := r.nodes[name]; node != nil {
+        return node.peerURL, true
+    }
+
+    return "", false
+}
+
+// Retrieves the peer URLs for all nodes.
+func (r *Registry) PeerURLs() []string {
+    r.Lock()
+    defer r.Unlock()
+
+    // Retrieve a list of all nodes.
+    e, err := s.Get(RegistryKey, false, false, 0, 0)
+    if err != nil {
+        return make([]string, 0)
+    }
+
+    // Lookup the URL for each one.
+    urls := make([]string, 0)
+    for _, pair := range e.KVPairs {
+        urls = append(urls, r.peerURL(pair.Key))
+    }
+
+    return urls
+}
+
+// Loads the given node by name from the store into the cache.
+func (r *Registry) load(name string) {
+    if name == "" {
+        return
+    }
+
+    // Retrieve from store.
+    e, err := etcdStore.Get(path.Join(RegistryKey, name), false, false, 0, 0)
+    if err != nil {
+        return
+    }
+
+    // Parse as a query string.
+    m, err := url.ParseQuery(e.Value)
+    if err != nil {
+        panic(fmt.Sprintf("Failed to parse machines entry: %s", name))
+    }
+
+    // Create node.
+    r.nodes[name] := &node{
+        url: m["etcd"][0],
+        peerURL: m["raft"][0],
+        peerVersion: m["raftVersion"][0],
+    }
+}

server/remove_command.go

@@ -25,22 +25,20 @@ func (c *RemoveCommand) CommandName() string {
 // Remove a server from the cluster
 func (c *RemoveCommand) Apply(server *raft.Server) (interface{}, error) {
 	s, _ := server.StateMachine().(*store.Store)
-	r, _ := server.Context().(*RaftServer)
+	ps, _ := server.Context().(*PeerServer)
 
-	// remove machine in etcd storage
-	key := path.Join("_etcd/machines", c.Name)
+	// Remove node from the shared registry.
+	err := ps.registry.Unregister(c.Name, server.CommitIndex(), server.Term())
 
-	_, err := s.Delete(key, false, server.CommitIndex(), server.Term())
-	// delete from stats
-	delete(r.followersStats.Followers, c.Name)
+	// Delete from stats
+	delete(ps.followersStats.Followers, c.Name)
 
 	if err != nil {
 		return []byte{0}, err
 	}
 
-	// remove peer in raft
+	// Remove peer in raft
 	err = server.RemovePeer(c.Name)
-
 	if err != nil {
 		return []byte{0}, err
 	}
@@ -52,7 +50,7 @@ func (c *RemoveCommand) Apply(server *raft.Server) (interface{}, error) {
 		// and the node has sent out a join request in this
 		// start. It is sure that this node received a new remove
 		// command and need to be removed
-		if server.CommitIndex() > r.joinIndex && r.joinIndex != 0 {
+		if server.CommitIndex() > ps.joinIndex && ps.joinIndex != 0 {
 			debugf("server [%s] is removed", server.Name())
 			os.Exit(0)
 		} else {

server/server.go

@@ -4,7 +4,6 @@ import (
 	"net/http"
 	"net/url"
 
-	"github.com/coreos/etcd/command"
 	"github.com/coreos/go-raft"
 	"github.com/gorilla/mux"
 )
@@ -13,7 +12,7 @@ import (
 type Server interface {
 	CommitIndex() uint64
 	Term() uint64
-	Dispatch(command.Command, http.ResponseWriter, *http.Request)
+	Dispatch(raft.Command, http.ResponseWriter, *http.Request)
 }
 
 // This is the default implementation of the Server interface.

server/timeout.go

@@ -0,0 +1,11 @@
+package server
+
+const (
+    // The amount of time to elapse without a heartbeat before becoming a candidate.
+    ElectionTimeout  = 200 * time.Millisecond
+
+    // The frequency by which heartbeats are sent to followers.
+    HeartbeatTimeout = 50 * time.Millisecond
+
+    RetryInterval    = 10
+)

server/transporter.go

@@ -0,0 +1,226 @@
+package server
+
+import (
+    "bytes"
+    "crypto/tls"
+    "encoding/json"
+    "fmt"
+    "io"
+    "net"
+    "net/http"
+    "time"
+
+    "github.com/coreos/go-raft"
+)
+
+// Timeout for setup internal raft http connection
+// This should not exceed 3 * RTT
+var dailTimeout = 3 * HeartbeatTimeout
+
+// Timeout for setup internal raft http connection + receive response header
+// This should not exceed 3 * RTT + RTT
+var responseHeaderTimeout = 4 * HeartbeatTimeout
+
+// Timeout for receiving the response body from the server
+// This should not exceed election timeout
+var tranTimeout = ElectionTimeout
+
+// Transporter layer for communication between raft nodes
+type transporter struct {
+    client     *http.Client
+    transport  *http.Transport
+    raftServer *raftServer
+}
+
+// Create transporter using by raft server
+// Create http or https transporter based on
+// whether the user give the server cert and key
+func newTransporter(scheme string, tlsConf tls.Config, raftServer *raftServer) *transporter {
+    t := transporter{}
+
+    tr := &http.Transport{
+        Dial: dialWithTimeout,
+        ResponseHeaderTimeout: responseHeaderTimeout,
+    }
+
+    if scheme == "https" {
+        tr.TLSClientConfig = &tlsConf
+        tr.DisableCompression = true
+    }
+
+    t.client = &http.Client{Transport: tr}
+    t.transport = tr
+    t.raftServer = raftServer
+
+    return &t
+}
+
+// Dial with timeout
+func dialWithTimeout(network, addr string) (net.Conn, error) {
+    return net.DialTimeout(network, addr, dailTimeout)
+}
+
+// Sends AppendEntries RPCs to a peer when the server is the leader.
+func (t *transporter) SendAppendEntriesRequest(server *raft.Server, peer *raft.Peer, req *raft.AppendEntriesRequest) *raft.AppendEntriesResponse {
+    var aersp *raft.AppendEntriesResponse
+    var b bytes.Buffer
+
+    json.NewEncoder(&b).Encode(req)
+
+    size := b.Len()
+
+    t.raftServer.serverStats.SendAppendReq(size)
+
+    u, _ := nameToRaftURL(peer.Name)
+
+    debugf("Send LogEntries to %s ", u)
+
+    thisFollowerStats, ok := t.raftServer.followersStats.Followers[peer.Name]
+
+    if !ok { //this is the first time this follower has been seen
+        thisFollowerStats = &raftFollowerStats{}
+        thisFollowerStats.Latency.Minimum = 1 << 63
+        t.raftServer.followersStats.Followers[peer.Name] = thisFollowerStats
+    }
+
+    start := time.Now()
+
+    resp, httpRequest, err := t.Post(fmt.Sprintf("%s/log/append", u), &b)
+
+    end := time.Now()
+
+    if err != nil {
+        debugf("Cannot send AppendEntriesRequest to %s: %s", u, err)
+        if ok {
+            thisFollowerStats.Fail()
+        }
+    } else {
+        if ok {
+            thisFollowerStats.Succ(end.Sub(start))
+        }
+    }
+
+    if resp != nil {
+        defer resp.Body.Close()
+
+        t.CancelWhenTimeout(httpRequest)
+
+        aersp = &raft.AppendEntriesResponse{}
+        if err := json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
+            return aersp
+        }
+
+    }
+
+    return aersp
+}
+
+// Sends RequestVote RPCs to a peer when the server is the candidate.
+func (t *transporter) SendVoteRequest(server *raft.Server, peer *raft.Peer, req *raft.RequestVoteRequest) *raft.RequestVoteResponse {
+    var rvrsp *raft.RequestVoteResponse
+    var b bytes.Buffer
+    json.NewEncoder(&b).Encode(req)
+
+    u, _ := nameToRaftURL(peer.Name)
+    debugf("Send Vote to %s", u)
+
+    resp, httpRequest, err := t.Post(fmt.Sprintf("%s/vote", u), &b)
+
+    if err != nil {
+        debugf("Cannot send VoteRequest to %s : %s", u, err)
+    }
+
+    if resp != nil {
+        defer resp.Body.Close()
+
+        t.CancelWhenTimeout(httpRequest)
+
+        rvrsp := &raft.RequestVoteResponse{}
+        if err := json.NewDecoder(resp.Body).Decode(&rvrsp); err == nil || err == io.EOF {
+            return rvrsp
+        }
+
+    }
+    return rvrsp
+}
+
+// Sends SnapshotRequest RPCs to a peer when the server is the candidate.
+func (t *transporter) SendSnapshotRequest(server *raft.Server, peer *raft.Peer, req *raft.SnapshotRequest) *raft.SnapshotResponse {
+    var aersp *raft.SnapshotResponse
+    var b bytes.Buffer
+    json.NewEncoder(&b).Encode(req)
+
+    u, _ := nameToRaftURL(peer.Name)
+    debugf("Send Snapshot to %s [Last Term: %d, LastIndex %d]", u,
+        req.LastTerm, req.LastIndex)
+
+    resp, httpRequest, err := t.Post(fmt.Sprintf("%s/snapshot", u), &b)
+
+    if err != nil {
+        debugf("Cannot send SendSnapshotRequest to %s : %s", u, err)
+    }
+
+    if resp != nil {
+        defer resp.Body.Close()
+
+        t.CancelWhenTimeout(httpRequest)
+
+        aersp = &raft.SnapshotResponse{}
+        if err = json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
+
+            return aersp
+        }
+    }
+
+    return aersp
+}
+
+// Sends SnapshotRecoveryRequest RPCs to a peer when the server is the candidate.
+func (t *transporter) SendSnapshotRecoveryRequest(server *raft.Server, peer *raft.Peer, req *raft.SnapshotRecoveryRequest) *raft.SnapshotRecoveryResponse {
+    var aersp *raft.SnapshotRecoveryResponse
+    var b bytes.Buffer
+    json.NewEncoder(&b).Encode(req)
+
+    u, _ := nameToRaftURL(peer.Name)
+    debugf("Send SnapshotRecovery to %s [Last Term: %d, LastIndex %d]", u,
+        req.LastTerm, req.LastIndex)
+
+    resp, _, err := t.Post(fmt.Sprintf("%s/snapshotRecovery", u), &b)
+
+    if err != nil {
+        debugf("Cannot send SendSnapshotRecoveryRequest to %s : %s", u, err)
+    }
+
+    if resp != nil {
+        defer resp.Body.Close()
+        aersp = &raft.SnapshotRecoveryResponse{}
+
+        if err = json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
+            return aersp
+        }
+    }
+
+    return aersp
+}
+
+// Send server side POST request
+func (t *transporter) Post(urlStr string, body io.Reader) (*http.Response, *http.Request, error) {
+    req, _ := http.NewRequest("POST", urlStr, body)
+    resp, err := t.client.Do(req)
+    return resp, req, err
+}
+
+// Send server side GET request
+func (t *transporter) Get(urlStr string) (*http.Response, *http.Request, error) {
+    req, _ := http.NewRequest("GET", urlStr, nil)
+    resp, err := t.client.Do(req)
+    return resp, req, err
+}
+
+// Cancel the on fly HTTP transaction when timeout happens.
+func (t *transporter) CancelWhenTimeout(req *http.Request) {
+    go func() {
+        time.Sleep(ElectionTimeout)
+        t.transport.CancelRequest(req)
+    }()
+}

transporter_test.go → server/transporter_test.go

@@ -1,4 +1,4 @@
-package main
+package server
 
 import (
 	"crypto/tls"

server/util.go

@@ -0,0 +1,17 @@
+package server
+
+import (
+    "fmt"
+    "net/http"
+    "github.com/coreos/etcd/log"
+)
+
+func decodeJsonRequest(req *http.Request, data interface{}) error {
+    decoder := json.NewDecoder(req.Body)
+    if err := decoder.Decode(&data); err != nil && err != io.EOF {
+        log.Warnf("Malformed json request: %v", err)
+        return fmt.Errorf("Malformed json request: %v", err)
+    }
+    return nil
+}
+

server/v2/handlers.go

@@ -12,10 +12,6 @@ import (
 	"github.com/coreos/go-raft"
 )
 
-//-------------------------------------------------------------------
-// Handlers to handle etcd-store related request via etcd url
-//-------------------------------------------------------------------
-
 func NewEtcdMuxer() *http.ServeMux {
 	// external commands
 	router := mux.NewRouter()

version.go → server/version.go

@@ -1,8 +1,8 @@
-package main
+package server
 
-const version = "v2"
+const Version = "v2"
 
 // TODO: The release version (generated from the git tag) will be the raft
 // protocol version for now. When things settle down we will fix it like the
 // client API above.
-const raftVersion = releaseVersion
+const PeerVersion = releaseVersion

snapshot.go

@@ -1,36 +0,0 @@
-package main
-
-import (
-	"time"
-)
-
-// basic conf.
-// TODO: find a good policy to do snapshot
-type snapshotConf struct {
-	// Etcd will check if snapshot is need every checkingInterval
-	checkingInterval time.Duration
-	// The number of writes when the last snapshot happened
-	lastWrites uint64
-	// If the incremental number of writes since the last snapshot
-	// exceeds the write Threshold, etcd will do a snapshot
-	writesThr uint64
-}
-
-var snapConf *snapshotConf
-
-func (r *raftServer) newSnapshotConf() *snapshotConf {
-	// check snapshot every 3 seconds and the threshold is 20K
-	return &snapshotConf{time.Second * 3, 0, 20 * 1000}
-}
-
-func (r *raftServer) monitorSnapshot() {
-	for {
-		time.Sleep(snapConf.checkingInterval)
-		//currentWrites := etcdStore.TotalWrites() - snapConf.lastWrites
-		currentWrites := 0
-		if uint64(currentWrites) > snapConf.writesThr {
-			r.TakeSnapshot()
-			snapConf.lastWrites = 0
-		}
-	}
-}

command/create_command.go → store/create_command.go

@@ -1,12 +1,15 @@
-package command
+package store
 
 import (
 	"github.com/coreos/etcd/log"
-	"github.com/coreos/etcd/store"
 	"github.com/coreos/go-raft"
 	"time"
 )
 
+func init() {
+    raft.RegisterCommand(&CreateCommand{})
+}
+
 // Create command
 type CreateCommand struct {
 	Key               string    `json:"key"`
@@ -23,7 +26,7 @@ func (c *CreateCommand) CommandName() string {
 
 // Create node
 func (c *CreateCommand) Apply(server *raft.Server) (interface{}, error) {
-	s, _ := server.StateMachine().(*store.Store)
+	s, _ := server.StateMachine().(*Store)
 
 	e, err := s.Create(c.Key, c.Value, c.IncrementalSuffix, c.Force, c.ExpireTime, server.CommitIndex(), server.Term())
 

command/delete_command.go → store/delete_command.go

@@ -1,11 +1,14 @@
-package command
+package store
 
 import (
 	"github.com/coreos/etcd/log"
-	"github.com/coreos/etcd/store"
 	"github.com/coreos/go-raft"
 )
 
+func init() {
+    raft.RegisterCommand(&DeleteCommand{})
+}
+
 // The DeleteCommand removes a key from the Store.
 type DeleteCommand struct {
 	Key       string `json:"key"`
@@ -19,7 +22,7 @@ func (c *DeleteCommand) CommandName() string {
 
 // Delete the key
 func (c *DeleteCommand) Apply(server *raft.Server) (interface{}, error) {
-	s, _ := server.StateMachine().(*store.Store)
+	s, _ := server.StateMachine().(*Store)
 
 	e, err := s.Delete(c.Key, c.Recursive, server.CommitIndex(), server.Term())
 

store/store.go

@@ -401,16 +401,6 @@ func (s *Store) checkDir(parent *Node, dirName string) (*Node, *etcdErr.Error) {
 	return n, nil
 }
 
-// Returns the number of machines in the cluster.
-func (s *Store) MachineCount() int {
-	e, err := s.Get("/_etcd/machines", false, false, 0, 0)
-	if err != nil {
-		return 0
-	}
-
-	return len(e.KVPairs)
-}
-
 // Save function saves the static state of the store system.
 // Save function will not be able to save the state of watchers.
 // Save function will not save the parent field of the node. Or there will

command/test_and_set_command.go → store/test_and_set_command.go

@@ -1,13 +1,16 @@
-package command
+package store
 
 import (
 	"time"
 
 	"github.com/coreos/etcd/log"
-	"github.com/coreos/etcd/store"
 	"github.com/coreos/go-raft"
 )
 
+func init() {
+    raft.RegisterCommand(&TestAndSetCommand{})
+}
+
 // The TestAndSetCommand performs a conditional update on a key in the store.
 type TestAndSetCommand struct {
 	Key        string    `json:"key"`
@@ -24,7 +27,7 @@ func (c *TestAndSetCommand) CommandName() string {
 
 // Set the key-value pair if the current value of the key equals to the given prevValue
 func (c *TestAndSetCommand) Apply(server *raft.Server) (interface{}, error) {
-	s, _ := server.StateMachine().(*store.Store)
+	s, _ := server.StateMachine().(*Store)
 
 	e, err := s.TestAndSet(c.Key, c.PrevValue, c.PrevIndex,
 		c.Value, c.ExpireTime, server.CommitIndex(), server.Term())

command/update_command.go → store/update_command.go

@@ -1,13 +1,16 @@
-package command
+package store
 
 import (
 	"time"
 
 	"github.com/coreos/etcd/log"
-	"github.com/coreos/etcd/store"
 	"github.com/coreos/go-raft"
 )
 
+func init() {
+    raft.RegisterCommand(&UpdateCommand{})
+}
+
 // The UpdateCommand updates the value of a key in the Store.
 type UpdateCommand struct {
 	Key        string    `json:"key"`
@@ -22,7 +25,7 @@ func (c *UpdateCommand) CommandName() string {
 
 // Update node
 func (c *UpdateCommand) Apply(server *raft.Server) (interface{}, error) {
-	s, _ := server.StateMachine().(*store.Store)
+	s, _ := server.StateMachine().(*Store)
 
 	e, err := s.Update(c.Key, c.Value, c.ExpireTime, server.CommitIndex(), server.Term())
 

transporter.go

@@ -1,233 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"crypto/tls"
-	"encoding/json"
-	"fmt"
-	"io"
-	"net"
-	"net/http"
-	"time"
-
-	"github.com/coreos/go-raft"
-)
-
-// Timeout for setup internal raft http connection
-// This should not exceed 3 * RTT
-var dailTimeout = 3 * HeartbeatTimeout
-
-// Timeout for setup internal raft http connection + receive response header
-// This should not exceed 3 * RTT + RTT
-var responseHeaderTimeout = 4 * HeartbeatTimeout
-
-// Timeout for receiving the response body from the server
-// This should not exceed election timeout
-var tranTimeout = ElectionTimeout
-
-// Transporter layer for communication between raft nodes
-type transporter struct {
-	client     *http.Client
-	transport  *http.Transport
-	raftServer *raftServer
-}
-
-// Create transporter using by raft server
-// Create http or https transporter based on
-// whether the user give the server cert and key
-func newTransporter(scheme string, tlsConf tls.Config, raftServer *raftServer) *transporter {
-	t := transporter{}
-
-	tr := &http.Transport{
-		Dial: dialWithTimeout,
-		ResponseHeaderTimeout: responseHeaderTimeout,
-	}
-
-	if scheme == "https" {
-		tr.TLSClientConfig = &tlsConf
-		tr.DisableCompression = true
-	}
-
-	t.client = &http.Client{Transport: tr}
-	t.transport = tr
-	t.raftServer = raftServer
-
-	return &t
-}
-
-// Dial with timeout
-func dialWithTimeout(network, addr string) (net.Conn, error) {
-	return net.DialTimeout(network, addr, dailTimeout)
-}
-
-// Sends AppendEntries RPCs to a peer when the server is the leader.
-func (t *transporter) SendAppendEntriesRequest(server *raft.Server, peer *raft.Peer, req *raft.AppendEntriesRequest) *raft.AppendEntriesResponse {
-	var aersp *raft.AppendEntriesResponse
-	var b bytes.Buffer
-
-	json.NewEncoder(&b).Encode(req)
-
-	size := b.Len()
-
-	t.raftServer.serverStats.SendAppendReq(size)
-
-	u, _ := nameToRaftURL(peer.Name)
-
-	debugf("Send LogEntries to %s ", u)
-
-	thisFollowerStats, ok := t.raftServer.followersStats.Followers[peer.Name]
-
-	if !ok { //this is the first time this follower has been seen
-		thisFollowerStats = &raftFollowerStats{}
-		thisFollowerStats.Latency.Minimum = 1 << 63
-		t.raftServer.followersStats.Followers[peer.Name] = thisFollowerStats
-	}
-
-	start := time.Now()
-
-	resp, httpRequest, err := t.Post(fmt.Sprintf("%s/log/append", u), &b)
-
-	end := time.Now()
-
-	if err != nil {
-		debugf("Cannot send AppendEntriesRequest to %s: %s", u, err)
-		if ok {
-			thisFollowerStats.Fail()
-		}
-	} else {
-		if ok {
-			thisFollowerStats.Succ(end.Sub(start))
-		}
-	}
-
-	if resp != nil {
-		defer resp.Body.Close()
-
-		t.CancelWhenTimeout(httpRequest)
-
-		aersp = &raft.AppendEntriesResponse{}
-		if err := json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
-			return aersp
-		}
-
-	}
-
-	return aersp
-}
-
-// Sends RequestVote RPCs to a peer when the server is the candidate.
-func (t *transporter) SendVoteRequest(server *raft.Server, peer *raft.Peer, req *raft.RequestVoteRequest) *raft.RequestVoteResponse {
-	var rvrsp *raft.RequestVoteResponse
-	var b bytes.Buffer
-	json.NewEncoder(&b).Encode(req)
-
-	u, _ := nameToRaftURL(peer.Name)
-	debugf("Send Vote to %s", u)
-
-	resp, httpRequest, err := t.Post(fmt.Sprintf("%s/vote", u), &b)
-
-	if err != nil {
-		debugf("Cannot send VoteRequest to %s : %s", u, err)
-	}
-
-	if resp != nil {
-		defer resp.Body.Close()
-
-		t.CancelWhenTimeout(httpRequest)
-
-		rvrsp := &raft.RequestVoteResponse{}
-		if err := json.NewDecoder(resp.Body).Decode(&rvrsp); err == nil || err == io.EOF {
-			return rvrsp
-		}
-
-	}
-	return rvrsp
-}
-
-// Sends SnapshotRequest RPCs to a peer when the server is the candidate.
-func (t *transporter) SendSnapshotRequest(server *raft.Server, peer *raft.Peer, req *raft.SnapshotRequest) *raft.SnapshotResponse {
-	var aersp *raft.SnapshotResponse
-	var b bytes.Buffer
-	json.NewEncoder(&b).Encode(req)
-
-	u, _ := nameToRaftURL(peer.Name)
-	debugf("Send Snapshot to %s [Last Term: %d, LastIndex %d]", u,
-		req.LastTerm, req.LastIndex)
-
-	resp, httpRequest, err := t.Post(fmt.Sprintf("%s/snapshot", u), &b)
-
-	if err != nil {
-		debugf("Cannot send SendSnapshotRequest to %s : %s", u, err)
-	}
-
-	if resp != nil {
-		defer resp.Body.Close()
-
-		t.CancelWhenTimeout(httpRequest)
-
-		aersp = &raft.SnapshotResponse{}
-		if err = json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
-
-			return aersp
-		}
-	}
-
-	return aersp
-}
-
-// Sends SnapshotRecoveryRequest RPCs to a peer when the server is the candidate.
-func (t *transporter) SendSnapshotRecoveryRequest(server *raft.Server, peer *raft.Peer, req *raft.SnapshotRecoveryRequest) *raft.SnapshotRecoveryResponse {
-	var aersp *raft.SnapshotRecoveryResponse
-	var b bytes.Buffer
-	json.NewEncoder(&b).Encode(req)
-
-	u, _ := nameToRaftURL(peer.Name)
-	debugf("Send SnapshotRecovery to %s [Last Term: %d, LastIndex %d]", u,
-		req.LastTerm, req.LastIndex)
-
-	resp, _, err := t.Post(fmt.Sprintf("%s/snapshotRecovery", u), &b)
-
-	if err != nil {
-		debugf("Cannot send SendSnapshotRecoveryRequest to %s : %s", u, err)
-	}
-
-	if resp != nil {
-		defer resp.Body.Close()
-		aersp = &raft.SnapshotRecoveryResponse{}
-
-		if err = json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
-			return aersp
-		}
-	}
-
-	return aersp
-}
-
-// Send server side POST request
-func (t *transporter) Post(urlStr string, body io.Reader) (*http.Response, *http.Request, error) {
-
-	req, _ := http.NewRequest("POST", urlStr, body)
-
-	resp, err := t.client.Do(req)
-
-	return resp, req, err
-
-}
-
-// Send server side GET request
-func (t *transporter) Get(urlStr string) (*http.Response, *http.Request, error) {
-
-	req, _ := http.NewRequest("GET", urlStr, nil)
-
-	resp, err := t.client.Do(req)
-
-	return resp, req, err
-}
-
-// Cancel the on fly HTTP transaction when timeout happens
-func (t *transporter) CancelWhenTimeout(req *http.Request) {
-	go func() {
-		time.Sleep(ElectionTimeout)
-		t.transport.CancelRequest(req)
-	}()
-}

util.go

@@ -88,33 +88,11 @@ func (r *raftServer) dispatch(c Command, w http.ResponseWriter, req *http.Reques
 
 func redirect(hostname string, w http.ResponseWriter, req *http.Request) {
 	path := req.URL.Path
-
 	url := hostname + path
-
 	debugf("Redirect to %s", url)
-
 	http.Redirect(w, req, url, http.StatusTemporaryRedirect)
 }
 
-func decodeJsonRequest(req *http.Request, data interface{}) error {
-	decoder := json.NewDecoder(req.Body)
-	if err := decoder.Decode(&data); err != nil && err != io.EOF {
-		warnf("Malformed json request: %v", err)
-		return fmt.Errorf("Malformed json request: %v", err)
-	}
-	return nil
-}
-
-func encodeJsonResponse(w http.ResponseWriter, status int, data interface{}) {
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(status)
-
-	if data != nil {
-		encoder := json.NewEncoder(w)
-		encoder.Encode(data)
-	}
-}
-
 // sanitizeURL will cleanup a host string in the format hostname:port and
 // attach a schema.
 func sanitizeURL(host string, defaultScheme string) string {