Update downgrade test to use snapshot

Signed-off-by: Geeta Gharpure <geetagh@amazon.com>

tests/e2e/cluster_downgrade_test.go

@@ -23,12 +23,14 @@ import (
 	"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"
 	clientv3 "go.etcd.io/etcd/client/v3"
+	"go.etcd.io/etcd/tests/v3/framework/config"
 	"go.etcd.io/etcd/tests/v3/framework/e2e"
 	"go.etcd.io/etcd/tests/v3/framework/testutils"
 )
@@ -67,7 +69,7 @@ func testDowngradeUpgrade(t *testing.T, clusterSize int) {
 	e2e.BeforeTest(t)
 
 	t.Logf("Create cluster with version %s", currentVersionStr)
-	epc := newCluster(t, clusterSize)
+	epc := newCluster(t, clusterSize, 10, t.TempDir())
 	for i := 0; i < len(epc.Procs); i++ {
 		validateVersion(t, epc.Cfg, epc.Procs[i], version.Versions{
 			Cluster: currentVersionStr,
@@ -76,6 +78,8 @@ func testDowngradeUpgrade(t *testing.T, clusterSize int) {
 		})
 	}
 	t.Logf("Cluster created")
+	generateSnapshot(t, 10, epc)
+	bm, bkv := getMembersAndKeys(t, epc)
 
 	t.Logf("etcdctl downgrade enable %s", lastVersionStr)
 	downgradeEnable(t, epc, lastVersion)
@@ -108,6 +112,10 @@ func testDowngradeUpgrade(t *testing.T, clusterSize int) {
 	}
 
 	t.Log("Downgrade complete")
+	am, akv := getMembersAndKeys(t, epc)
+	assert.Equal(t, bkv.Kvs, akv.Kvs)
+	assert.Equal(t, bm.Members, am.Members)
+
 	t.Logf("Starting upgrade process to %q", currentVersionStr)
 	for i := 0; i < len(epc.Procs); i++ {
 		t.Logf("Upgrading member %d", i)
@@ -129,9 +137,11 @@ func testDowngradeUpgrade(t *testing.T, clusterSize int) {
 	t.Log("Upgrade complete")
 }
 
-func newCluster(t *testing.T, clusterSize int) *e2e.EtcdProcessCluster {
+func newCluster(t *testing.T, clusterSize int, snapshotCount uint64, dataDir string) *e2e.EtcdProcessCluster {
 	epc, err := e2e.NewEtcdProcessCluster(context.TODO(), t,
 		e2e.WithClusterSize(clusterSize),
+		e2e.WithDataDirPath(dataDir),
+		e2e.WithSnapshotCount(snapshotCount),
 		e2e.WithKeepDataDir(true),
 	)
 	if err != nil {
@@ -243,3 +253,34 @@ func getMemberVersionByCurl(cfg *e2e.EtcdProcessClusterConfig, member e2e.EtcdPr
 	}
 	return result, nil
 }
+
+func generateSnapshot(t *testing.T, snapshotCount uint64, epc *e2e.EtcdProcessCluster) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	t.Log("Adding and removing keys")
+	cc, err := e2e.NewEtcdctl(epc.Cfg.Client, epc.EndpointsGRPC())
+	assert.NoError(t, err)
+
+	var i uint64
+	for i = 0; i < snapshotCount*3; i++ {
+		err := cc.Put(ctx, fmt.Sprintf("%d", i), "1", config.PutOptions{})
+		assert.NoError(t, err)
+	}
+}
+
+func getMembersAndKeys(t *testing.T, epc *e2e.EtcdProcessCluster) (*clientv3.MemberListResponse, *clientv3.GetResponse) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	cc, err := e2e.NewEtcdctl(epc.Cfg.Client, epc.EndpointsGRPC())
+	assert.NoError(t, err)
+
+	kvs, err := cc.Get(ctx, "", config.GetOptions{Prefix: true})
+	assert.NoError(t, err)
+
+	members, err := cc.MemberList(ctx, false)
+	assert.NoError(t, err)
+
+	return members, kvs
+}