Merge pull request #2205 from yichengq/315

migrate: support standby mode upgrade

etcdmain/etcd.go

@@ -360,7 +360,7 @@ func makeMemberDir(dir string) error {
 			// Link it to the subdir and keep the v1 file at the original
 			// location, so v0.4 etcd can still bootstrap if the upgrade
 			// failed.
-			if err := os.Link(path.Join(dir, name), path.Join(membdir, name)); err != nil {
+			if err := os.Symlink(path.Join(dir, name), path.Join(membdir, name)); err != nil {
 				return err
 			}
 		case v2Files.Contains(name):

migrate/functional/README.md

@@ -7,7 +7,7 @@ This functional test suite deploys a etcd cluster using processes, and asserts e
 Dependencies
 ------------
 
-The test suite can only be run in linux system. It's recommended to run this in a virtual machine environment on CoreOS (e.g. using coreos-vagrant). The only dependency for the tests not provided on the CoreOS image is go.
+The test suite can only be run in CoreOS system. It's recommended to run this in a virtual machine environment on CoreOS (e.g. using coreos-vagrant). The only dependency for the tests not provided on the CoreOS image is go.
 
 Usage
 -----

migrate/functional/member.go

@@ -54,7 +54,6 @@ func NewProcWithDefaultFlags(path string) *Proc {
 	}
 	// always expect to use start_desired_verson mode
 	p.Env = append(p.Env,
-		"ETCD_ALLOW_LEGACY_MODE=true",
 		"ETCD_BINARY_DIR="+binDir,
 	)
 	return p
@@ -178,6 +177,11 @@ func (p *Proc) Terminate() {
 
 type ProcGroup []*Proc
 
+func NewProcInProcGroupWithV1Flags(path string, num int, idx int) *Proc {
+	pg := NewProcGroupWithV1Flags(path, num)
+	return pg[idx]
+}
+
 func NewProcGroupWithV1Flags(path string, num int) ProcGroup {
 	pg := make([]*Proc, num)
 	pg[0] = NewProcWithDefaultFlags(path)

migrate/functional/upgrade_test.go

@@ -1,6 +1,7 @@
 package functional
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
@@ -262,6 +263,84 @@ func TestJoinV1ClusterViaDiscovery(t *testing.T) {
 	}
 }
 
+func TestUpgradeV1Standby(t *testing.T) {
+	// get v1 standby data dir
+	pg := NewProcGroupWithV1Flags(v1BinPath, 3)
+	if err := pg.Start(); err != nil {
+		t.Fatalf("Start error: %v", err)
+	}
+	req, err := http.NewRequest("PUT", pg[0].PeerURL+"/v2/admin/config", bytes.NewBufferString(`{"activeSize":3,"removeDelay":1800,"syncInterval":5}`))
+	if err != nil {
+		t.Fatalf("NewRequest error: %v", err)
+	}
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("http Do error: %v", err)
+	}
+	if resp.StatusCode != http.StatusOK {
+		t.Fatalf("status = %d, want %d", resp.StatusCode, http.StatusOK)
+	}
+
+	p := NewProcInProcGroupWithV1Flags(v2BinPath, 4, 3)
+	if err := p.Start(); err != nil {
+		t.Fatalf("Start error: %v", err)
+	}
+	fmt.Println("checking new member is in standby mode...")
+	mustExist(path.Join(p.DataDir, "standby_info"))
+	ver, err := checkInternalVersion(p.URL)
+	if err != nil {
+		t.Fatalf("checkVersion error: %v", err)
+	}
+	if ver != "1" {
+		t.Errorf("internal version = %s, want %s", ver, "1")
+	}
+
+	fmt.Println("upgrading the whole cluster...")
+	cmd := exec.Command(etcdctlBinPath, "upgrade", "--peer-url", pg[0].PeerURL)
+	if err := cmd.Start(); err != nil {
+		t.Fatalf("Start error: %v", err)
+	}
+	if err := cmd.Wait(); err != nil {
+		t.Fatalf("Wait error: %v", err)
+	}
+	fmt.Println("waiting until peer-mode etcd exits...")
+	if err := pg.Wait(); err != nil {
+		t.Fatalf("Wait error: %v", err)
+	}
+	fmt.Println("restarting the peer-mode etcd...")
+	npg := NewProcGroupWithV1Flags(v2BinPath, 3)
+	npg.InheritDataDir(pg)
+	npg.CleanUnsuppportedV1Flags()
+	if err := npg.Start(); err != nil {
+		t.Fatalf("Start error: %v", err)
+	}
+	defer npg.Terminate()
+	fmt.Println("waiting until standby-mode etcd exits...")
+	if err := p.Wait(); err != nil {
+		t.Fatalf("Wait error: %v", err)
+	}
+	fmt.Println("restarting the standby-mode etcd...")
+	np := NewProcInProcGroupWithV1Flags(v2BinPath, 4, 3)
+	np.SetDataDir(p.DataDir)
+	np.CleanUnsuppportedV1Flags()
+	if err := np.Start(); err != nil {
+		t.Fatalf("Start error: %v", err)
+	}
+	defer np.Terminate()
+
+	fmt.Println("checking the new member is in v2 proxy mode...")
+	ver, err = checkInternalVersion(np.URL)
+	if err != nil {
+		t.Fatalf("checkVersion error: %v", err)
+	}
+	if ver != "2" {
+		t.Errorf("internal version = %s, want %s", ver, "1")
+	}
+	if _, err := os.Stat(path.Join(np.DataDir, "proxy")); err != nil {
+		t.Errorf("stat proxy dir error = %v, want nil", err)
+	}
+}
+
 func absPathFromEnv(name string) string {
 	path, err := filepath.Abs(os.Getenv(name))
 	if err != nil {

migrate/standby.go

@@ -0,0 +1,70 @@
+// Copyright 2015 CoreOS, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package migrate
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+)
+
+type StandbyInfo4 struct {
+	Running      bool
+	Cluster      []*MachineMessage
+	SyncInterval float64
+}
+
+// MachineMessage represents information about a peer or standby in the registry.
+type MachineMessage struct {
+	Name      string `json:"name"`
+	State     string `json:"state"`
+	ClientURL string `json:"clientURL"`
+	PeerURL   string `json:"peerURL"`
+}
+
+func (si *StandbyInfo4) ClientURLs() []string {
+	var urls []string
+	for _, m := range si.Cluster {
+		urls = append(urls, m.ClientURL)
+	}
+	return urls
+}
+
+func (si *StandbyInfo4) InitialCluster() string {
+	b := &bytes.Buffer{}
+	first := true
+	for _, m := range si.Cluster {
+		if !first {
+			fmt.Fprintf(b, ",")
+		}
+		first = false
+		fmt.Fprintf(b, "%s=%s", m.Name, m.PeerURL)
+	}
+	return b.String()
+}
+
+func DecodeStandbyInfo4FromFile(path string) (*StandbyInfo4, error) {
+	var info StandbyInfo4
+	file, err := os.OpenFile(path, os.O_RDONLY, 0600)
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+	if err = json.NewDecoder(file).Decode(&info); err != nil {
+		return nil, err
+	}
+	return &info, nil
+}

migrate/starter/starter.go

@@ -30,8 +30,9 @@ import (
 	"github.com/coreos/etcd/client"
 	"github.com/coreos/etcd/etcdmain"
 	"github.com/coreos/etcd/migrate"
+	"github.com/coreos/etcd/pkg/fileutil"
 	"github.com/coreos/etcd/pkg/flags"
-	"github.com/coreos/etcd/wal"
+	"github.com/coreos/etcd/pkg/types"
 
 	"github.com/coreos/etcd/Godeps/_workspace/src/golang.org/x/net/context"
 )
@@ -41,80 +42,147 @@ type version string
 const (
 	internalV1      version = "1"
 	internalV2      version = "2"
+	internalV2Proxy version = "2.proxy"
 	internalUnknown version = "unknown"
 
+	v0_4      version = "v0.4"
+	v2_0      version = "v2.0"
+	v2_0Proxy version = "v2.0 proxy"
+	empty     version = "empty"
+	unknown   version = "unknown"
+
 	defaultInternalV1etcdBinaryDir = "/usr/libexec/etcd/versions/"
 )
 
+var (
+	v2SpecialFlags = []string{
+		"initial-cluster",
+		"listen-peer-urls",
+		"listen-client-urls",
+		"proxy",
+	}
+)
+
 func StartDesiredVersion(args []string) {
-	switch checkStartVersion(args) {
+	fs, err := parseConfig(args)
+	if err != nil {
+		return
+	}
+
+	ver := checkInternalVersion(fs)
+	log.Printf("starter: start etcd version %s", ver)
+	switch ver {
 	case internalV1:
 		startInternalV1()
 	case internalV2:
+	case internalV2Proxy:
+		if _, err := os.Stat(standbyInfo4(fs.Lookup("data-dir").Value.String())); err != nil {
+			log.Printf("starter: Detect standby_info file exists, and add --proxy=on flag to ensure it runs in v2.0 proxy mode.")
+			log.Printf("starter: Before removing v0.4 data, --proxy=on flag MUST be added.")
+		}
+		// append proxy flag to args to trigger proxy mode
+		os.Args = append(os.Args, "-proxy=on")
 	default:
-		log.Panicf("migrate: unhandled start version")
+		log.Panicf("starter: unhandled start version")
 	}
 }
 
-func checkStartVersion(args []string) version {
-	fs, err := parseConfig(args)
-	if err != nil {
-		return internalV2
-	}
+func checkInternalVersion(fs *flag.FlagSet) version {
 	// If it uses 2.0 env var explicitly, start 2.0
-	if fs.Lookup("initial-cluster").Value.String() != "" {
-		return internalV2
+	for _, name := range v2SpecialFlags {
+		if fs.Lookup(name).Value.String() != "" {
+			return internalV2
+		}
 	}
 
 	dataDir := fs.Lookup("data-dir").Value.String()
 	if dataDir == "" {
-		log.Fatalf("migrate: please set ETCD_DATA_DIR for etcd")
+		log.Fatalf("starter: please set --data-dir or ETCD_DATA_DIR for etcd")
 	}
 	// check the data directory
-	walVersion, err := wal.DetectVersion(dataDir)
+	ver, err := checkVersion(dataDir)
 	if err != nil {
-		log.Fatalf("migrate: failed to detect etcd version in %v: %v", dataDir, err)
+		log.Fatalf("starter: failed to detect etcd version in %v: %v", dataDir, err)
 	}
-	log.Printf("migrate: detect etcd version %s in %s", walVersion, dataDir)
-	switch walVersion {
-	case wal.WALv0_5:
+	log.Printf("starter: detect etcd version %s in %s", ver, dataDir)
+	switch ver {
+	case v2_0:
 		return internalV2
-	case wal.WALv0_4:
-		// TODO: standby case
-		// if it is standby guy:
-		//     print out detect standby mode
-		//     go to WALNotExist case
-		//     if want to start with 2.0:
-		//         remove old data dir to avoid auto migration
-		//         try to let it fallback? or use local proxy file?
-		ver, err := checkStartVersionByDataDir4(dataDir)
+	case v2_0Proxy:
+		return internalV2Proxy
+	case v0_4:
+		standbyInfo, err := migrate.DecodeStandbyInfo4FromFile(standbyInfo4(dataDir))
+		if err != nil && !os.IsNotExist(err) {
+			log.Fatalf("starter: failed to decode standbyInfo in %v: %v", dataDir, err)
+		}
+		inStandbyMode := standbyInfo != nil && standbyInfo.Running
+		if inStandbyMode {
+			ver, err := checkInternalVersionByClientURLs(standbyInfo.ClientURLs(), clientTLSInfo(fs))
+			if err != nil {
+				log.Printf("starter: failed to check start version through peers: %v", err)
+				return internalV1
+			}
+			if ver == internalV2 {
+				os.Args = append(os.Args, "-initial-cluster", standbyInfo.InitialCluster())
+				return internalV2Proxy
+			}
+			return ver
+		}
+		ver, err := checkInternalVersionByDataDir4(dataDir)
 		if err != nil {
-			log.Fatalf("migrate: failed to check start version in %v: %v", dataDir, err)
+			log.Fatalf("starter: failed to check start version in %v: %v", dataDir, err)
 		}
 		return ver
-	case wal.WALUnknown:
-		log.Fatalf("migrate: unknown etcd version in %v", dataDir)
-	case wal.WALNotExist:
+	case empty:
 		discovery := fs.Lookup("discovery").Value.String()
-		peers := trimSplit(fs.Lookup("peers").Value.String(), ",")
-		peerTLSInfo := &TLSInfo{
-			CAFile:   fs.Lookup("peer-ca-file").Value.String(),
-			CertFile: fs.Lookup("peer-cert-file").Value.String(),
-			KeyFile:  fs.Lookup("peer-key-file").Value.String(),
+		dpeers, err := getPeersFromDiscoveryURL(discovery)
+		if err != nil {
+			log.Printf("starter: failed to get peers from discovery %s: %v", discovery, err)
 		}
-		ver, err := checkStartVersionByMembers(discovery, peers, peerTLSInfo)
+		peerStr := fs.Lookup("peers").Value.String()
+		ppeers := getPeersFromPeersFlag(peerStr, peerTLSInfo(fs))
+
+		urls := getClientURLsByPeerURLs(append(dpeers, ppeers...), peerTLSInfo(fs))
+		ver, err := checkInternalVersionByClientURLs(urls, clientTLSInfo(fs))
 		if err != nil {
-			log.Printf("migrate: failed to check start version through peers: %v", err)
-			break
+			log.Printf("starter: failed to check start version through peers: %v", err)
+			return internalV2
 		}
 		return ver
-	default:
-		log.Panicf("migrate: unhandled etcd version in %v", dataDir)
 	}
-	return internalV2
+	// never reach here
+	log.Panicf("starter: unhandled etcd version in %v", dataDir)
+	return internalUnknown
 }
 
-func checkStartVersionByDataDir4(dataDir string) (version, error) {
+func checkVersion(dataDir string) (version, error) {
+	names, err := fileutil.ReadDir(dataDir)
+	if err != nil {
+		if os.IsNotExist(err) {
+			err = nil
+		}
+		return empty, err
+	}
+	if len(names) == 0 {
+		return empty, nil
+	}
+	nameSet := types.NewUnsafeSet(names...)
+	if nameSet.ContainsAll([]string{"member"}) {
+		return v2_0, nil
+	}
+	if nameSet.ContainsAll([]string{"proxy"}) {
+		return v2_0Proxy, nil
+	}
+	if nameSet.ContainsAll([]string{"snapshot", "conf", "log"}) {
+		return v0_4, nil
+	}
+	if nameSet.ContainsAll([]string{"standby_info"}) {
+		return v0_4, nil
+	}
+	return unknown, fmt.Errorf("failed to check version")
+}
+
+func checkInternalVersionByDataDir4(dataDir string) (version, error) {
 	// check v0.4 snapshot
 	snap4, err := migrate.DecodeLatestSnapshot4FromDir(snapDir4(dataDir))
 	if err != nil {
@@ -153,51 +221,50 @@ func checkStartVersionByDataDir4(dataDir string) (version, error) {
 	return internalV1, nil
 }
 
-func checkStartVersionByMembers(discoverURL string, peers []string, tls *TLSInfo) (version, error) {
-	tr := &http.Transport{}
-	if tls.Scheme() == "https" {
-		tlsConfig, err := tls.ClientConfig()
-		if err != nil {
-			return internalUnknown, err
-		}
-		tr.TLSClientConfig = tlsConfig
-	}
-	c := &http.Client{Transport: tr}
-
-	possiblePeers, err := getPeersFromDiscoveryURL(discoverURL)
+func getClientURLsByPeerURLs(peers []string, tls *TLSInfo) []string {
+	c, err := newDefaultClient(tls)
 	if err != nil {
-		return internalUnknown, err
+		log.Printf("starter: new client error: %v", err)
+		return nil
 	}
-	for _, p := range peers {
-		possiblePeers = append(possiblePeers, tls.Scheme()+"://"+p)
-	}
-
-	for _, p := range possiblePeers {
-		resp, err := c.Get(p + "/etcdURL")
+	var urls []string
+	for _, u := range peers {
+		resp, err := c.Get(u + "/etcdURL")
 		if err != nil {
-			log.Printf("migrate: failed to get /etcdURL from %s", p)
+			log.Printf("starter: failed to get /etcdURL from %s", u)
 			continue
 		}
 		b, err := ioutil.ReadAll(resp.Body)
 		if err != nil {
-			log.Printf("migrate: failed to read body from %s", p)
+			log.Printf("starter: failed to read body from %s", u)
 			continue
 		}
-		resp, err = c.Get(string(b) + "/version")
+		urls = append(urls, string(b))
+	}
+	return urls
+}
+
+func checkInternalVersionByClientURLs(urls []string, tls *TLSInfo) (version, error) {
+	c, err := newDefaultClient(tls)
+	if err != nil {
+		return internalUnknown, err
+	}
+	for _, u := range urls {
+		resp, err := c.Get(u + "/version")
 		if err != nil {
-			log.Printf("migrate: failed to get /version from %s", p)
+			log.Printf("starter: failed to get /version from %s", u)
 			continue
 		}
-		b, err = ioutil.ReadAll(resp.Body)
+		b, err := ioutil.ReadAll(resp.Body)
 		if err != nil {
-			log.Printf("migrate: failed to read body from %s", p)
+			log.Printf("starter: failed to read body from %s", u)
 			continue
 		}
 
 		var m map[string]string
 		err = json.Unmarshal(b, &m)
 		if err != nil {
-			log.Printf("migrate: failed to unmarshal body %s from %s", b, p)
+			log.Printf("starter: failed to unmarshal body %s from %s", b, u)
 			continue
 		}
 		switch m["internalVersion"] {
@@ -206,10 +273,10 @@ func checkStartVersionByMembers(discoverURL string, peers []string, tls *TLSInfo
 		case "2":
 			return internalV2, nil
 		default:
-			log.Printf("migrate: unrecognized internal version %s from %s", m["internalVersion"], p)
+			log.Printf("starter: unrecognized internal version %s from %s", m["internalVersion"], u)
 		}
 	}
-	return internalUnknown, fmt.Errorf("failed to get version from peers %v", possiblePeers)
+	return internalUnknown, fmt.Errorf("failed to get version from urls %v", urls)
 }
 
 func getPeersFromDiscoveryURL(discoverURL string) ([]string, error) {
@@ -246,6 +313,14 @@ func getPeersFromDiscoveryURL(discoverURL string) ([]string, error) {
 	return peers, nil
 }
 
+func getPeersFromPeersFlag(str string, tls *TLSInfo) []string {
+	peers := trimSplit(str, ",")
+	for i, p := range peers {
+		peers[i] = tls.Scheme() + "://" + p
+	}
+	return peers
+}
+
 func startInternalV1() {
 	p := os.Getenv("ETCD_BINARY_DIR")
 	if p == "" {
@@ -254,10 +329,22 @@ func startInternalV1() {
 	p = path.Join(p, "1")
 	err := syscall.Exec(p, os.Args, syscall.Environ())
 	if err != nil {
-		log.Fatalf("migrate: failed to execute internal v1 etcd: %v", err)
+		log.Fatalf("starter: failed to execute internal v1 etcd: %v", err)
 	}
 }
 
+func newDefaultClient(tls *TLSInfo) (*http.Client, error) {
+	tr := &http.Transport{}
+	if tls.Scheme() == "https" {
+		tlsConfig, err := tls.ClientConfig()
+		if err != nil {
+			return nil, err
+		}
+		tr.TLSClientConfig = tlsConfig
+	}
+	return &http.Client{Transport: tr}, nil
+}
+
 type value struct {
 	s string
 }
@@ -285,6 +372,22 @@ func parseConfig(args []string) (*flag.FlagSet, error) {
 	return fs, nil
 }
 
+func clientTLSInfo(fs *flag.FlagSet) *TLSInfo {
+	return &TLSInfo{
+		CAFile:   fs.Lookup("ca-file").Value.String(),
+		CertFile: fs.Lookup("cert-file").Value.String(),
+		KeyFile:  fs.Lookup("key-file").Value.String(),
+	}
+}
+
+func peerTLSInfo(fs *flag.FlagSet) *TLSInfo {
+	return &TLSInfo{
+		CAFile:   fs.Lookup("peer-ca-file").Value.String(),
+		CertFile: fs.Lookup("peer-cert-file").Value.String(),
+		KeyFile:  fs.Lookup("peer-key-file").Value.String(),
+	}
+}
+
 func snapDir4(dataDir string) string {
 	return path.Join(dataDir, "snapshot")
 }
@@ -293,6 +396,10 @@ func logFile4(dataDir string) string {
 	return path.Join(dataDir, "log")
 }
 
+func standbyInfo4(dataDir string) string {
+	return path.Join(dataDir, "standby_info")
+}
+
 func trimSplit(s, sep string) []string {
 	trimmed := strings.Split(s, sep)
 	for i := range trimmed {