Add randomness in robustness cluster process version to test mixed version scenarios.

tests/e2e/etcd_mix_versions_test.go

@@ -130,12 +130,13 @@ func mixVersionsSnapshotTestByMockPartition(t *testing.T, cfg *e2e.EtcdProcessCl
 		t.Skipf("%q does not exist", e2e.BinPath.EtcdLastRelease)
 	}
 
+	clusterOptions := []e2e.EPClusterOption{e2e.WithConfig(cfg), e2e.WithSnapshotCount(10)}
+	// TODO: remove version check after 3.5.14 release.
+	if cfg.Version == e2e.CurrentVersion {
+		clusterOptions = append(clusterOptions, e2e.WithSnapshotCatchUpEntries(10))
+	}
 	t.Logf("Create an etcd cluster with %d member", cfg.ClusterSize)
-	epc, err := e2e.NewEtcdProcessCluster(context.TODO(), t,
-		e2e.WithConfig(cfg),
-		e2e.WithSnapshotCount(10),
-		e2e.WithSnapshotCatchUpEntries(10),
-	)
+	epc, err := e2e.NewEtcdProcessCluster(context.TODO(), t, clusterOptions...)
 	require.NoError(t, err, "failed to start etcd cluster: %v", err)
 	defer func() {
 		derr := epc.Close()
@@ -161,7 +162,7 @@ func mixVersionsSnapshotTestByMockPartition(t *testing.T, cfg *e2e.EtcdProcessCl
 	assertKVHash(t, epc)
 
 	leaderEPC = epc.Procs[epc.WaitLeader(t)]
-	if leaderEPC.Config().ExecPath == e2e.BinPath.Etcd {
+	if cfg.Version == e2e.CurrentVersion {
 		t.Log("Verify logs to check snapshot be sent from leader to follower")
 		e2e.AssertProcessLogs(t, leaderEPC, "sent database snapshot")
 	}

tests/framework/e2e/cluster.go

@@ -151,8 +151,11 @@ type EtcdProcessClusterConfig struct {
 
 	// Cluster setup config
 
-	ClusterSize  int
-	RollingStart bool
+	ClusterSize int
+	// InitialLeaderIndex makes sure the leader is the ith proc
+	// when the cluster starts if it is specified (>=0).
+	InitialLeaderIndex int
+	RollingStart       bool
 	// BaseDataDirPath specifies the data-dir for the members. If test cases
 	// do not specify `BaseDataDirPath`, then e2e framework creates a
 	// temporary directory for each member; otherwise, it creates a
@@ -180,10 +183,10 @@ type EtcdProcessClusterConfig struct {
 
 func DefaultConfig() *EtcdProcessClusterConfig {
 	cfg := &EtcdProcessClusterConfig{
-		ClusterSize: 3,
-		CN:          true,
-
-		ServerConfig: *embed.NewConfig(),
+		ClusterSize:        3,
+		CN:                 true,
+		InitialLeaderIndex: -1,
+		ServerConfig:       *embed.NewConfig(),
 	}
 	cfg.ServerConfig.InitialClusterToken = "new"
 	return cfg
@@ -207,6 +210,10 @@ func WithVersion(version ClusterVersion) EPClusterOption {
 	return func(c *EtcdProcessClusterConfig) { c.Version = version }
 }
 
+func WithInitialLeaderIndex(i int) EPClusterOption {
+	return func(c *EtcdProcessClusterConfig) { c.InitialLeaderIndex = i }
+}
+
 func WithDataDirPath(path string) EPClusterOption {
 	return func(c *EtcdProcessClusterConfig) { c.BaseDataDirPath = path }
 }
@@ -398,6 +405,16 @@ func InitEtcdProcessCluster(t testing.TB, cfg *EtcdProcessClusterConfig) (*EtcdP
 		cfg.ServerConfig.SnapshotCount = etcdserver.DefaultSnapshotCount
 	}
 
+	// validate SnapshotCatchUpEntries could be set for at least one member
+	if cfg.ServerConfig.SnapshotCatchUpEntries != etcdserver.DefaultSnapshotCatchUpEntries {
+		if !CouldSetSnapshotCatchupEntries(BinPath.Etcd) {
+			return nil, fmt.Errorf("cannot set SnapshotCatchUpEntries for current etcd version: %s", BinPath.Etcd)
+		}
+		if cfg.Version == LastVersion && !CouldSetSnapshotCatchupEntries(BinPath.EtcdLastRelease) {
+			return nil, fmt.Errorf("cannot set SnapshotCatchUpEntries for last etcd version: %s", BinPath.EtcdLastRelease)
+		}
+	}
+
 	etcdCfgs := cfg.EtcdAllServerProcessConfigs(t)
 	epc := &EtcdProcessCluster{
 		Cfg:     cfg,
@@ -437,7 +454,11 @@ func StartEtcdProcessCluster(ctx context.Context, t testing.TB, epc *EtcdProcess
 			t.Skip("please run 'make gofail-enable && make build' before running the test")
 		}
 	}
-
+	if cfg.InitialLeaderIndex >= 0 {
+		if err := epc.MoveLeader(ctx, t, cfg.InitialLeaderIndex); err != nil {
+			return nil, fmt.Errorf("failed to move leader: %v", err)
+		}
+	}
 	return epc, nil
 }
 
@@ -570,27 +591,6 @@ func (cfg *EtcdProcessClusterConfig) EtcdServerProcessConfig(tb testing.TB, i in
 		args = append(args, "--discovery="+cfg.Discovery)
 	}
 
-	defaultValues := values(*embed.NewConfig())
-	overrideValues := values(cfg.ServerConfig)
-	for flag, value := range overrideValues {
-		if defaultValue := defaultValues[flag]; value == "" || value == defaultValue {
-			continue
-		}
-		if flag == "experimental-snapshot-catchup-entries" && !(cfg.Version == CurrentVersion || (cfg.Version == MinorityLastVersion && i <= cfg.ClusterSize/2) || (cfg.Version == QuorumLastVersion && i > cfg.ClusterSize/2)) {
-			continue
-		}
-		args = append(args, fmt.Sprintf("--%s=%s", flag, value))
-	}
-	envVars := map[string]string{}
-	for key, value := range cfg.EnvVars {
-		envVars[key] = value
-	}
-	var gofailPort int
-	if cfg.GoFailEnabled {
-		gofailPort = (i+1)*10000 + 2381
-		envVars["GOFAIL_HTTP"] = fmt.Sprintf("127.0.0.1:%d", gofailPort)
-	}
-
 	var execPath string
 	switch cfg.Version {
 	case CurrentVersion:
@@ -613,6 +613,27 @@ func (cfg *EtcdProcessClusterConfig) EtcdServerProcessConfig(tb testing.TB, i in
 		panic(fmt.Sprintf("Unknown cluster version %v", cfg.Version))
 	}
 
+	defaultValues := values(*embed.NewConfig())
+	overrideValues := values(cfg.ServerConfig)
+	for flag, value := range overrideValues {
+		if defaultValue := defaultValues[flag]; value == "" || value == defaultValue {
+			continue
+		}
+		if flag == "experimental-snapshot-catchup-entries" && !CouldSetSnapshotCatchupEntries(execPath) {
+			continue
+		}
+		args = append(args, fmt.Sprintf("--%s=%s", flag, value))
+	}
+	envVars := map[string]string{}
+	for key, value := range cfg.EnvVars {
+		envVars[key] = value
+	}
+	var gofailPort int
+	if cfg.GoFailEnabled {
+		gofailPort = (i+1)*10000 + 2381
+		envVars["GOFAIL_HTTP"] = fmt.Sprintf("127.0.0.1:%d", gofailPort)
+	}
+
 	return &EtcdServerProcessConfig{
 		lg:                  cfg.Logger,
 		ExecPath:            execPath,
@@ -1050,3 +1071,31 @@ func (epc *EtcdProcessCluster) WaitMembersForLeader(ctx context.Context, t testi
 	t.Fatal("impossible path of execution")
 	return -1
 }
+
+// MoveLeader moves the leader to the ith process.
+func (epc *EtcdProcessCluster) MoveLeader(ctx context.Context, t testing.TB, i int) error {
+	if i < 0 || i >= len(epc.Procs) {
+		return fmt.Errorf("invalid index: %d, must between 0 and %d", i, len(epc.Procs)-1)
+	}
+	t.Logf("moving leader to Procs[%d]", i)
+	oldLeader := epc.WaitMembersForLeader(ctx, t, epc.Procs)
+	if oldLeader == i {
+		t.Logf("Procs[%d] is already the leader", i)
+		return nil
+	}
+	resp, err := epc.Procs[i].Etcdctl().Status(ctx)
+	if err != nil {
+		return err
+	}
+	memberID := resp[0].Header.MemberId
+	err = epc.Procs[oldLeader].Etcdctl().MoveLeader(ctx, memberID)
+	if err != nil {
+		return err
+	}
+	newLeader := epc.WaitMembersForLeader(ctx, t, epc.Procs)
+	if newLeader != i {
+		t.Fatalf("expect new leader to be Procs[%d] but got Procs[%d]", i, newLeader)
+	}
+	t.Logf("moved leader from Procs[%d] to Procs[%d]", oldLeader, i)
+	return nil
+}

tests/framework/e2e/cluster_test.go

@@ -15,17 +15,22 @@
 package e2e
 
 import (
+	"fmt"
 	"testing"
 
+	"github.com/coreos/go-semver/semver"
 	"github.com/stretchr/testify/assert"
 )
 
 func TestEtcdServerProcessConfig(t *testing.T) {
+	v3_5_12 := semver.Version{Major: 3, Minor: 5, Patch: 12}
+	v3_5_13 := semver.Version{Major: 3, Minor: 5, Patch: 13}
 	tcs := []struct {
 		name                 string
 		config               *EtcdProcessClusterConfig
 		expectArgsNotContain []string
 		expectArgsContain    []string
+		mockBinaryVersion    *semver.Version
 	}{
 		{
 			name:   "Default",
@@ -73,17 +78,37 @@ func TestEtcdServerProcessConfig(t *testing.T) {
 			expectArgsContain: []string{
 				"--experimental-snapshot-catchup-entries=100",
 			},
+			mockBinaryVersion: &v3_5_13,
 		},
 		{
-			name:   "CatchUpEntriesLastVersion",
+			name:   "CatchUpEntriesNoVersion",
 			config: NewConfig(WithSnapshotCatchUpEntries(100), WithVersion(LastVersion)),
 			expectArgsNotContain: []string{
 				"--experimental-snapshot-catchup-entries=100",
 			},
 		},
+		{
+			name:   "CatchUpEntriesOldVersion",
+			config: NewConfig(WithSnapshotCatchUpEntries(100), WithVersion(LastVersion)),
+			expectArgsNotContain: []string{
+				"--experimental-snapshot-catchup-entries=100",
+			},
+			mockBinaryVersion: &v3_5_12,
+		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.name, func(t *testing.T) {
+			var mockGetVersionFromBinary func(binaryPath string) (*semver.Version, error)
+			if tc.mockBinaryVersion == nil {
+				mockGetVersionFromBinary = func(binaryPath string) (*semver.Version, error) {
+					return nil, fmt.Errorf("could not get binary version")
+				}
+			} else {
+				mockGetVersionFromBinary = func(binaryPath string) (*semver.Version, error) {
+					return tc.mockBinaryVersion, nil
+				}
+			}
+			setGetVersionFromBinary(t, mockGetVersionFromBinary)
 			args := tc.config.EtcdServerProcessConfig(t, 0).Args
 			if len(tc.expectArgsContain) != 0 {
 				assert.Subset(t, args, tc.expectArgsContain)

tests/framework/e2e/etcd_process.go

@@ -485,7 +485,10 @@ func parseFailpointsBody(body io.Reader) (map[string]string, error) {
 	return failpoints, nil
 }
 
-func GetVersionFromBinary(binaryPath string) (*semver.Version, error) {
+var GetVersionFromBinary = func(binaryPath string) (*semver.Version, error) {
+	if !fileutil.Exist(binaryPath) {
+		return nil, fmt.Errorf("binary path does not exist: %s", binaryPath)
+	}
 	lines, err := RunUtilCompletion([]string{binaryPath, "--version"}, nil)
 	if err != nil {
 		return nil, fmt.Errorf("could not find binary version from %s, err: %w", binaryPath, err)
@@ -508,3 +511,22 @@ func GetVersionFromBinary(binaryPath string) (*semver.Version, error) {
 
 	return nil, fmt.Errorf("could not find version in binary output of %s, lines outputted were %v", binaryPath, lines)
 }
+
+// setGetVersionFromBinary changes the GetVersionFromBinary function to a mock in testing.
+func setGetVersionFromBinary(tb testing.TB, f func(binaryPath string) (*semver.Version, error)) {
+	origGetVersionFromBinary := GetVersionFromBinary
+	GetVersionFromBinary = f
+	tb.Cleanup(func() {
+		GetVersionFromBinary = origGetVersionFromBinary
+	})
+}
+
+func CouldSetSnapshotCatchupEntries(execPath string) bool {
+	v, err := GetVersionFromBinary(execPath)
+	if err != nil {
+		return false
+	}
+	// snapshot-catchup-entries flag was backported in https://github.com/etcd-io/etcd/pull/17808
+	v3_5_13 := semver.Version{Major: 3, Minor: 5, Patch: 13}
+	return v.Compare(v3_5_13) >= 0
+}

tests/framework/e2e/etcdctl.go

@@ -312,6 +312,13 @@ func (ctl *EtcdctlV3) MemberPromote(ctx context.Context, id uint64) (*clientv3.M
 	return &resp, err
 }
 
+// MoveLeader requests current leader to transfer its leadership to the transferee.
+// Request must be made to the leader.
+func (ctl *EtcdctlV3) MoveLeader(ctx context.Context, transfereeID uint64) error {
+	_, err := SpawnWithExpectLines(ctx, ctl.cmdArgs("move-leader", fmt.Sprintf("%x", transfereeID)), nil, expect.ExpectedResponse{Value: "Leadership transferred"})
+	return err
+}
+
 func (ctl *EtcdctlV3) cmdArgs(args ...string) []string {
 	cmdArgs := []string{BinPath.Etcdctl}
 	for k, v := range ctl.flags() {

tests/framework/e2e/flags.go

@@ -69,6 +69,8 @@ func InitFlags() {
 	certDirDef := FixturesDir
 
 	binDir := flag.String("bin-dir", binDirDef, "The directory for store etcd and etcdctl binaries.")
+	binLastRelease := flag.String("bin-last-release", "", "The path for the last release etcd binary.")
+
 	flag.StringVar(&CertDir, "cert-dir", certDirDef, "The directory for store certificate files.")
 	flag.Parse()
 
@@ -79,6 +81,9 @@ func InitFlags() {
 		Etcdutl:         *binDir + "/etcdutl",
 		LazyFS:          *binDir + "/lazyfs",
 	}
+	if *binLastRelease != "" {
+		BinPath.EtcdLastRelease = *binLastRelease
+	}
 	CertPath = CertDir + "/server.crt"
 	PrivateKeyPath = CertDir + "/server.key.insecure"
 	CaPath = CertDir + "/ca.crt"

tests/robustness/failpoint/cluster.go

@@ -135,8 +135,9 @@ func (f memberReplace) Name() string {
 	return "MemberReplace"
 }
 
-func (f memberReplace) Available(config e2e.EtcdProcessClusterConfig, _ e2e.EtcdProcess) bool {
-	return config.ClusterSize > 1
+func (f memberReplace) Available(config e2e.EtcdProcessClusterConfig, member e2e.EtcdProcess) bool {
+	// a lower etcd version may not be able to join a cluster with higher cluster version.
+	return config.ClusterSize > 1 && (config.Version == e2e.QuorumLastVersion || member.Config().ExecPath == e2e.BinPath.Etcd)
 }
 
 func getID(ctx context.Context, cc clientv3.Cluster, name string) (id uint64, found bool, err error) {

tests/robustness/failpoint/network.go

@@ -59,7 +59,7 @@ func (tb triggerBlackhole) Trigger(ctx context.Context, t *testing.T, member e2e
 func (tb triggerBlackhole) Available(config e2e.EtcdProcessClusterConfig, process e2e.EtcdProcess) bool {
 	// Avoid triggering failpoint if waiting for failpoint would take too long to fit into timeout.
 	// Number of required entries for snapshot depends on etcd configuration.
-	if tb.waitTillSnapshot && entriesToGuaranteeSnapshot(config) > 200 {
+	if tb.waitTillSnapshot && (entriesToGuaranteeSnapshot(config) > 200 || !e2e.CouldSetSnapshotCatchupEntries(process.Config().ExecPath)) {
 		return false
 	}
 	return config.ClusterSize > 1 && process.PeerProxy() != nil

tests/robustness/makefile.mk

@@ -5,9 +5,13 @@ test-robustness-reports:
 
 # Test previous release branches
 
+.PHONY: test-robustness-release-3.6
+test-robustness-release-3.6: /tmp/etcd-release-3.6-failpoints/bin /tmp/etcd-release-3.5-failpoints/bin
+	GO_TEST_FLAGS="$${GO_TEST_FLAGS} --bin-dir=/tmp/etcd-release-3.6-failpoints/bin --bin-last-release=/tmp/etcd-release-3.5-failpoints/bin/etcd" make test-robustness
+
 .PHONY: test-robustness-release-3.5
-test-robustness-release-3.5: /tmp/etcd-release-3.5-failpoints/bin
-	GO_TEST_FLAGS="$${GO_TEST_FLAGS} --bin-dir=/tmp/etcd-release-3.5-failpoints/bin" make test-robustness
+test-robustness-release-3.5: /tmp/etcd-release-3.5-failpoints/bin /tmp/etcd-release-3.4-failpoints/bin
+	GO_TEST_FLAGS="$${GO_TEST_FLAGS} --bin-dir=/tmp/etcd-release-3.5-failpoints/bin --bin-last-release=/tmp/etcd-release-3.4-failpoints/bin/etcd" make test-robustness
 
 .PHONY: test-robustness-release-3.4
 test-robustness-release-3.4: /tmp/etcd-release-3.4-failpoints/bin
@@ -72,6 +76,14 @@ $(GOPATH)/bin/gofail: tools/mod/go.mod tools/mod/go.sum
 	  make gofail-enable; \
 	  make build;
 
+/tmp/etcd-release-3.6-failpoints/bin: $(GOPATH)/bin/gofail
+	rm -rf /tmp/etcd-release-3.6-failpoints/
+	mkdir -p /tmp/etcd-release-3.6-failpoints/
+	cd /tmp/etcd-release-3.6-failpoints/; \
+	  git clone --depth 1 --branch main https://github.com/etcd-io/etcd.git .; \
+	  make gofail-enable; \
+	  make build;	  
+
 /tmp/etcd-v3.5.2-failpoints/bin:
 /tmp/etcd-v3.5.4-failpoints/bin:
 /tmp/etcd-v3.5.5-failpoints/bin:

tests/robustness/options/server_config_options.go

@@ -49,3 +49,11 @@ func WithExperimentalWatchProgressNotifyInterval(input ...time.Duration) e2e.EPC
 		c.ServerConfig.ExperimentalWatchProgressNotifyInterval = input[internalRand.Intn(len(input))]
 	}
 }
+
+func WithVersion(input ...e2e.ClusterVersion) e2e.EPClusterOption {
+	return func(c *e2e.EtcdProcessClusterConfig) { c.Version = input[internalRand.Intn(len(input))] }
+}
+
+func WithInitialLeaderIndex(input ...int) e2e.EPClusterOption {
+	return func(c *e2e.EtcdProcessClusterConfig) { c.InitialLeaderIndex = input[internalRand.Intn(len(input))] }
+}