Add cluster downgrade test.

Signed-off-by: Siyuan Zhang <[email protected]>

tests/e2e/cluster_downgrade_test.go

@@ -0,0 +1,345 @@
+// Copyright 2024 The etcd Authors
+//
+// 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 e2e
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/coreos/go-semver/semver"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+
+	"go.etcd.io/etcd/api/v3/version"
+	"go.etcd.io/etcd/client/pkg/v3/fileutil"
+	"go.etcd.io/etcd/client/pkg/v3/types"
+	clientv3 "go.etcd.io/etcd/client/v3"
+	"go.etcd.io/etcd/server/v3/datadir"
+	"go.etcd.io/etcd/server/v3/etcdserver"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/membership"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/snap"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/v2store"
+	"go.etcd.io/etcd/tests/v3/framework/e2e"
+)
+
+func TestDowngradeUpgradeClusterOf1(t *testing.T) {
+	testDowngradeUpgrade(t, 1, false)
+}
+
+func TestDowngradeUpgradeClusterOf3(t *testing.T) {
+	testDowngradeUpgrade(t, 3, false)
+}
+
+func TestDowngradeUpgradeClusterOf1WithSnapshot(t *testing.T) {
+	testDowngradeUpgrade(t, 1, true)
+}
+
+func TestDowngradeUpgradeClusterOf3WithSnapshot(t *testing.T) {
+	testDowngradeUpgrade(t, 3, true)
+}
+
+func testDowngradeUpgrade(t *testing.T, clusterSize int, triggerSnapshot bool) {
+	currentEtcdBinary := e2e.BinPath
+	lastReleaseBinary := e2e.BinPathLastRelease
+	if !fileutil.Exist(lastReleaseBinary) {
+		t.Skipf("%q does not exist", lastReleaseBinary)
+	}
+
+	currentVersion, err := e2e.GetVersionFromBinary(currentEtcdBinary)
+	require.NoError(t, err)
+	// wipe any pre-release suffix like -alpha.0 we see commonly in builds
+	currentVersion.PreRelease = ""
+
+	lastVersion, err := e2e.GetVersionFromBinary(lastReleaseBinary)
+	require.NoError(t, err)
+
+	require.Equalf(t, lastVersion.Minor, currentVersion.Minor-1, "unexpected minor version difference")
+	currentVersionStr := currentVersion.String()
+	lastVersionStr := lastVersion.String()
+
+	currentClusterVersion := semver.New(currentVersionStr)
+	currentClusterVersion.Patch = 0
+	currentClusterVersionStr := currentClusterVersion.String()
+
+	lastClusterVersion := semver.New(lastVersionStr)
+	lastClusterVersion.Patch = 0
+	lastClusterVersionStr := lastClusterVersion.String()
+
+	e2e.BeforeTest(t)
+
+	t.Logf("Create cluster with version %s", currentVersionStr)
+	snapshotCount := 10
+	epc := newCluster(t, clusterSize, snapshotCount)
+	for i := 0; i < len(epc.Procs); i++ {
+		validateVersion(t, epc.Cfg, epc.Procs[i], version.Versions{
+			Cluster: currentClusterVersionStr,
+			Server:  version.Version,
+		})
+	}
+	cc := epc.Etcdctl()
+	t.Logf("Cluster created")
+	if len(epc.Procs) > 1 {
+		t.Log("Waiting health interval to required to make membership changes")
+		time.Sleep(etcdserver.HealthInterval)
+	}
+
+	t.Log("Adding member to test membership, but a learner avoid breaking quorum")
+	resp, err := cc.MemberAddAsLearner("fake1", []string{"http://127.0.0.1:1001"})
+	require.NoError(t, err)
+	if triggerSnapshot {
+		t.Logf("Generating snapshot")
+		generateSnapshot(t, snapshotCount, cc)
+		verifySnapshot(t, epc)
+	}
+	t.Log("Removing learner to test membership")
+	_, err = cc.MemberRemove(resp.Member.ID)
+	require.NoError(t, err)
+	beforeMembers, beforeKV := getMembersAndKeys(t, cc)
+
+	t.Logf("Starting downgrade process to %q", lastVersionStr)
+	for i := 0; i < len(epc.Procs); i++ {
+		t.Logf("Downgrading member %d by running %s binary", i, lastReleaseBinary)
+		stopEtcd(t, epc.Procs[i])
+		startEtcd(t, epc.Procs[i], lastReleaseBinary)
+	}
+
+	t.Log("All members downgraded, validating downgrade")
+	for i := 0; i < len(epc.Procs); i++ {
+		validateVersion(t, epc.Cfg, epc.Procs[i], version.Versions{
+			Cluster: lastClusterVersionStr,
+			Server:  lastVersionStr,
+		})
+	}
+
+	t.Log("Downgrade complete")
+	afterMembers, afterKV := getMembersAndKeys(t, cc)
+	assert.Equal(t, beforeKV.Kvs, afterKV.Kvs)
+	assert.Equal(t, beforeMembers.Members, afterMembers.Members)
+
+	if len(epc.Procs) > 1 {
+		t.Log("Waiting health interval to required to make membership changes")
+		time.Sleep(etcdserver.HealthInterval)
+	}
+	t.Log("Adding learner to test membership, but avoid breaking quorum")
+	resp, err = cc.MemberAddAsLearner("fake2", []string{"http://127.0.0.1:1002"})
+	require.NoError(t, err)
+	if triggerSnapshot {
+		t.Logf("Generating snapshot")
+		generateSnapshot(t, snapshotCount, cc)
+		verifySnapshot(t, epc)
+	}
+	t.Log("Removing learner to test membership")
+	_, err = cc.MemberRemove(resp.Member.ID)
+	require.NoError(t, err)
+	beforeMembers, beforeKV = getMembersAndKeys(t, cc)
+
+	t.Logf("Starting upgrade process to %q", currentVersionStr)
+	for i := 0; i < len(epc.Procs); i++ {
+		t.Logf("Upgrading member %d", i)
+		stopEtcd(t, epc.Procs[i])
+		startEtcd(t, epc.Procs[i], currentEtcdBinary)
+		// NOTE: The leader has monitor to the cluster version, which will
+		// update cluster version. We don't need to check the transient
+		// version just in case that it might be flaky.
+	}
+
+	t.Log("All members upgraded, validating upgrade")
+	for i := 0; i < len(epc.Procs); i++ {
+		validateVersion(t, epc.Cfg, epc.Procs[i], version.Versions{
+			Cluster: currentClusterVersionStr,
+			Server:  version.Version,
+		})
+	}
+	t.Log("Upgrade complete")
+
+	afterMembers, afterKV = getMembersAndKeys(t, cc)
+	assert.Equal(t, beforeKV.Kvs, afterKV.Kvs)
+	assert.Equal(t, beforeMembers.Members, afterMembers.Members)
+}
+
+func newCluster(t *testing.T, clusterSize int, snapshotCount int) *e2e.EtcdProcessCluster {
+	copiedCfg := e2e.NewConfigNoTLS()
+	copiedCfg.ClusterSize = clusterSize
+	copiedCfg.SnapshotCount = snapshotCount
+	copiedCfg.KeepDataDir = true
+	copiedCfg.BasePeerScheme = "unix" // to avoid port conflict
+
+	epc, err := e2e.NewEtcdProcessCluster(t, copiedCfg)
+	if err != nil {
+		t.Fatalf("could not start etcd process cluster (%v)", err)
+	}
+	t.Cleanup(func() {
+		if errC := epc.Close(); errC != nil {
+			t.Fatalf("error closing etcd processes (%v)", errC)
+		}
+	})
+	return epc
+}
+
+func startEtcd(t *testing.T, ep e2e.EtcdProcess, execPath string) {
+	ep.Config().ExecPath = execPath
+	if execPath == e2e.BinPathLastRelease {
+		ep.Config().Args = addOrRemoveArg(ep.Config().Args, "--next-cluster-version-compatible", true)
+	} else {
+		ep.Config().Args = addOrRemoveArg(ep.Config().Args, "--next-cluster-version-compatible", false)
+	}
+	err := ep.Restart()
+	if err != nil {
+		t.Fatalf("could not start etcd process cluster (%v)", err)
+	}
+}
+
+func addOrRemoveArg(args []string, arg string, isAdd bool) []string {
+	newArgs := []string{}
+	for _, s := range args {
+		if s != arg {
+			newArgs = append(newArgs, s)
+		}
+	}
+	if isAdd {
+		newArgs = append(newArgs, arg)
+	}
+	return newArgs
+}
+
+func stopEtcd(t *testing.T, ep e2e.EtcdProcess) {
+	if err := ep.Stop(); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func validateVersion(t *testing.T, cfg *e2e.EtcdProcessClusterConfig, member e2e.EtcdProcess, expect version.Versions) {
+	executeWithTimeout(t, 30*time.Second, func() {
+		for {
+			result, err := getMemberVersionByCurl(cfg, member)
+			if err != nil {
+				cfg.Logger.Warn("failed to get member version and retrying", zap.Error(err), zap.String("member", member.Config().Name))
+				time.Sleep(time.Second)
+				continue
+			}
+			cfg.Logger.Info("Comparing versions", zap.String("member", member.Config().Name), zap.Any("got", result), zap.Any("want", expect))
+			if err := compareMemberVersion(expect, result); err != nil {
+				cfg.Logger.Warn("Versions didn't match retrying", zap.Error(err), zap.String("member", member.Config().Name))
+				time.Sleep(time.Second)
+				continue
+			}
+			cfg.Logger.Info("Versions match", zap.String("member", member.Config().Name))
+			break
+		}
+	})
+}
+
+func leader(t *testing.T, epc *e2e.EtcdProcessCluster) e2e.EtcdProcess {
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second*10)
+	defer cancel()
+	for i := 0; i < len(epc.Procs); i++ {
+		endpoints := epc.Procs[i].EndpointsGRPC()
+		cli, err := clientv3.New(clientv3.Config{
+			Endpoints:   endpoints,
+			DialTimeout: 3 * time.Second,
+		})
+		if err != nil {
+			t.Fatal(err)
+		}
+		defer cli.Close()
+		resp, err := cli.Status(ctx, endpoints[0])
+		if err != nil {
+			t.Fatal(err)
+		}
+		if resp.Header.GetMemberId() == resp.Leader {
+			return epc.Procs[i]
+		}
+	}
+	t.Fatal("Leader not found")
+	return nil
+}
+
+func compareMemberVersion(expect version.Versions, target version.Versions) error {
+	if expect.Server != "" && expect.Server != target.Server {
+		return fmt.Errorf("expect etcdserver version %v, but got %v", expect.Server, target.Server)
+	}
+
+	if expect.Cluster != "" && expect.Cluster != target.Cluster {
+		return fmt.Errorf("expect etcdcluster version %v, but got %v", expect.Cluster, target.Cluster)
+	}
+
+	return nil
+}
+
+func getMemberVersionByCurl(cfg *e2e.EtcdProcessClusterConfig, member e2e.EtcdProcess) (version.Versions, error) {
+	args := e2e.CURLPrefixArgsCluster(cfg, member, "GET", e2e.CURLReq{Endpoint: "/version"})
+	lines, err := e2e.RunUtilCompletion(args, nil)
+	if err != nil {
+		return version.Versions{}, err
+	}
+
+	data := strings.Join(lines, "\n")
+	result := version.Versions{}
+	if err := json.Unmarshal([]byte(data), &result); err != nil {
+		return version.Versions{}, fmt.Errorf("failed to unmarshal (%v): %w", data, err)
+	}
+	return result, nil
+}
+
+func generateSnapshot(t *testing.T, snapshotCount int, cc *e2e.Etcdctl) {
+	t.Logf("Adding keys")
+	for i := 0; i < snapshotCount*3; i++ {
+		err := cc.Put(fmt.Sprintf("%d", i), "1")
+		assert.NoError(t, err)
+	}
+}
+
+func verifySnapshot(t *testing.T, epc *e2e.EtcdProcessCluster) {
+	for i := range epc.Procs {
+		t.Logf("Verifying snapshot for member %d", i)
+		ss := snap.New(epc.Cfg.Logger, datadir.ToSnapDir(epc.Procs[i].Config().DataDirPath))
+		_, err := ss.Load()
+		assert.NoError(t, err)
+	}
+	t.Logf("All members have a valid snapshot")
+}
+
+func verifySnapshotMembers(t *testing.T, epc *e2e.EtcdProcessCluster, expectedMembers *clientv3.MemberListResponse) {
+	for i := range epc.Procs {
+		t.Logf("Verifying snapshot for member %d", i)
+		ss := snap.New(epc.Cfg.Logger, datadir.ToSnapDir(epc.Procs[i].Config().DataDirPath))
+		snap, err := ss.Load()
+		require.NoError(t, err)
+		st := v2store.New(etcdserver.StoreClusterPrefix, etcdserver.StoreKeysPrefix)
+		err = st.Recovery(snap.Data)
+		assert.NoError(t, err)
+		for _, m := range expectedMembers.Members {
+			_, err := st.Get(membership.MemberStoreKey(types.ID(m.ID)), true, true)
+			assert.NoError(t, err)
+		}
+		t.Logf("Verifed snapshot for member %d", i)
+	}
+	t.Log("All members have a valid snapshot")
+}
+
+func getMembersAndKeys(t *testing.T, cc *e2e.Etcdctl) (*clientv3.MemberListResponse, *clientv3.GetResponse) {
+	kvs, err := cc.GetWithPrefix("")
+	assert.NoError(t, err)
+
+	members, err := cc.MemberList()
+	assert.NoError(t, err)
+
+	return members, kvs
+}

tests/e2e/v3_curl_test.go

@@ -18,6 +18,7 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"fmt"
+	"math/rand"
 	"path"
 	"strconv"
 	"testing"
@@ -244,7 +245,7 @@ func testV3CurlAuth(cx ctlCtx) {
 			lineFunc   = func(txt string) bool { return true }
 		)
 
-		cmdArgs = e2e.CURLPrefixArgsCluster(cx.epc, "POST", e2e.CURLReq{Endpoint: path.Join(p, "/auth/authenticate"), Value: string(authreq)})
+		cmdArgs = e2e.CURLPrefixArgsCluster(cx.epc.Cfg, cx.epc.Procs[rand.Intn(cx.epc.Cfg.ClusterSize)], "POST", e2e.CURLReq{Endpoint: path.Join(p, "/auth/authenticate"), Value: string(authreq)})
 		proc, err := e2e.SpawnCmd(cmdArgs, cx.envMap)
 		testutil.AssertNil(cx.t, err)
 		defer proc.Close()
@@ -283,7 +284,7 @@ func testV3CurlCampaign(cx ctlCtx) {
 	if err != nil {
 		cx.t.Fatal(err)
 	}
-	cargs := e2e.CURLPrefixArgsCluster(cx.epc, "POST", e2e.CURLReq{
+	cargs := e2e.CURLPrefixArgsCluster(cx.epc.Cfg, cx.epc.Procs[rand.Intn(cx.epc.Cfg.ClusterSize)], "POST", e2e.CURLReq{
 		Endpoint: path.Join(cx.apiPrefix, "/election/campaign"),
 		Value:    string(cdata),
 	})