update etcd client to use both v3 and v2

v3 for >=1.22, v2 otherwise

cluster/reconcile.go

@@ -203,12 +203,14 @@ func addEtcdMembers(ctx context.Context, currentCluster, kubeCluster *Cluster, k
 	}
 	for _, etcdHost := range etcdToAdd {
 		// Check if the host already part of the cluster -- this will cover cluster with lost quorum
-		isEtcdMember, err := services.IsEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory, clientCert, clientKey)
+		isEtcdMember, err := services.IsEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory,
+			currentCluster.Version, clientCert, clientKey)
 		if err != nil {
 			return err
 		}
 		if !isEtcdMember {
-			if err := services.AddEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory, clientCert, clientKey); err != nil {
+			if err := services.AddEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory,
+				currentCluster.Version, clientCert, clientKey); err != nil {
 				return err
 			}
 		}
@@ -245,7 +247,8 @@ func deleteEtcdMembers(ctx context.Context, currentCluster, kubeCluster *Cluster
 
 	for _, etcdHost := range etcdToDelete {
 		etcdHost.IsEtcd = false
-		if err := services.RemoveEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory, clientCert, clientKey, etcdNodePlanMap); err != nil {
+		if err := services.RemoveEtcdMember(ctx, etcdHost, kubeCluster.EtcdHosts, currentCluster.LocalConnDialerFactory,
+			currentCluster.Version, clientCert, clientKey, etcdNodePlanMap); err != nil {
 			log.Warnf(ctx, "[reconcile] %v", err)
 			continue
 		}

services/etcd.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 	"time"
 
-	etcdclient "github.com/coreos/etcd/client"
+	"github.com/blang/semver"
 	"github.com/docker/docker/api/types/container"
 	"github.com/pkg/errors"
 	"github.com/rancher/rke/docker"
@@ -19,6 +19,7 @@ import (
 	v3 "github.com/rancher/rke/types"
 	"github.com/rancher/rke/util"
 	"github.com/sirupsen/logrus"
+	etcdclientv2 "go.etcd.io/etcd/client/v2"
 	"golang.org/x/sync/errgroup"
 )
 
@@ -167,7 +168,8 @@ func RemoveEtcdPlane(ctx context.Context, etcdHosts []*hosts.Host, force bool) e
 	return nil
 }
 
-func AddEtcdMember(ctx context.Context, toAddEtcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte) error {
+func AddEtcdMember(ctx context.Context, toAddEtcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory,
+	k8sVersion string, cert, key []byte) error {
 	log.Infof(ctx, "[add/%s] Adding member [etcd-%s] to etcd cluster", ETCDRole, toAddEtcdHost.HostnameOverride)
 	peerURL := fmt.Sprintf("https://%s:2380", toAddEtcdHost.InternalAddress)
 	added := false
@@ -175,16 +177,28 @@ func AddEtcdMember(ctx context.Context, toAddEtcdHost *hosts.Host, etcdHosts []*
 		if host.Address == toAddEtcdHost.Address {
 			continue
 		}
-		etcdClient, err := getEtcdClient(ctx, host, localConnDialerFactory, cert, key)
+		if etcdClientV3Range(k8sVersion) {
+			etcdClient, err := getEtcdClientV3(ctx, host, localConnDialerFactory, cert, key)
 			if err != nil {
 				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
 				continue
 			}
-		memAPI := etcdclient.NewMembersAPI(etcdClient)
+			if _, err := etcdClient.MemberAdd(ctx, []string{peerURL}); err != nil {
+				logrus.Debugf("Failed to Add etcd member [%s] from host: %v", host.Address, err)
+				continue
+			}
+		} else {
+			etcdClient, err := getEtcdClientV2(ctx, host, localConnDialerFactory, cert, key)
+			if err != nil {
+				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
+				continue
+			}
+			memAPI := etcdclientv2.NewMembersAPI(etcdClient)
 			if _, err := memAPI.Add(ctx, peerURL); err != nil {
 				logrus.Debugf("Failed to Add etcd member [%s] from host: %v", host.Address, err)
 				continue
 			}
+		}
 		added = true
 		break
 	}
@@ -195,17 +209,53 @@ func AddEtcdMember(ctx context.Context, toAddEtcdHost *hosts.Host, etcdHosts []*
 	return nil
 }
 
-func RemoveEtcdMember(ctx context.Context, toDeleteEtcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte, etcdNodePlanMap map[string]v3.RKEConfigNodePlan) error {
+func etcdClientV3Range(k8sVersion string) bool {
+	toMatch, err := semver.Make(k8sVersion[1:])
+	if err != nil {
+		logrus.Warnf("Cluster version [%s] can not be parsed as semver", k8sVersion)
+	}
+	etcdv3Range, err := semver.ParseRange(">=1.22.0-rancher0")
+	if err != nil {
+		logrus.Warnf("Failed to parse semver range for checking etcd v3 client range")
+	}
+	return etcdv3Range(toMatch)
+}
+
+func RemoveEtcdMember(ctx context.Context, toDeleteEtcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory,
+	k8sVersion string, cert, key []byte, etcdNodePlanMap map[string]v3.RKEConfigNodePlan) error {
 	log.Infof(ctx, "[remove/%s] Removing member [etcd-%s] from etcd cluster", ETCDRole, toDeleteEtcdHost.HostnameOverride)
-	var mID string
+	var mIDv3 uint64
+	var mIDv2 string
 	removed := false
 	for _, host := range etcdHosts {
-		etcdClient, err := getEtcdClient(ctx, host, localConnDialerFactory, cert, key)
+		if etcdClientV3Range(k8sVersion) {
+			etcdClient, err := getEtcdClientV3(ctx, host, localConnDialerFactory, cert, key)
 			if err != nil {
 				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
 				continue
 			}
-		memAPI := etcdclient.NewMembersAPI(etcdClient)
+			members, err := etcdClient.MemberList(ctx)
+			if err != nil {
+				logrus.Debugf("Failed to list etcd members from host [%s]: %v", host.Address, err)
+				continue
+			}
+			for _, member := range members.Members {
+				if member.Name == fmt.Sprintf("etcd-%s", toDeleteEtcdHost.HostnameOverride) {
+					mIDv3 = member.ID
+					break
+				}
+			}
+			if _, err := etcdClient.MemberRemove(ctx, mIDv3); err != nil {
+				logrus.Debugf("Failed to list etcd members from host [%s]: %v", host.Address, err)
+				continue
+			}
+		} else {
+			etcdClient, err := getEtcdClientV2(ctx, host, localConnDialerFactory, cert, key)
+			if err != nil {
+				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
+				continue
+			}
+			memAPI := etcdclientv2.NewMembersAPI(etcdClient)
 			members, err := memAPI.List(ctx)
 			if err != nil {
 				logrus.Debugf("Failed to list etcd members from host [%s]: %v", host.Address, err)
@@ -213,14 +263,16 @@ func RemoveEtcdMember(ctx context.Context, toDeleteEtcdHost *hosts.Host, etcdHos
 			}
 			for _, member := range members {
 				if member.Name == fmt.Sprintf("etcd-%s", toDeleteEtcdHost.HostnameOverride) {
-				mID = member.ID
+					mIDv2 = member.ID
 					break
 				}
 			}
-		if err := memAPI.Remove(ctx, mID); err != nil {
+			if err := memAPI.Remove(ctx, mIDv2); err != nil {
 				logrus.Debugf("Failed to list etcd members from host [%s]: %v", host.Address, err)
 				continue
 			}
+		}
+
 		etcdMemberDeletedTime := time.Now()
 		// Need to health check after successful member remove (especially for leader re-election)
 		// We will check all hosts to see if the cluster becomes healthy
@@ -278,20 +330,41 @@ func ReloadEtcdCluster(ctx context.Context, readyEtcdHosts []*hosts.Host, newHos
 	return nil
 }
 
-func IsEtcdMember(ctx context.Context, etcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte) (bool, error) {
+func IsEtcdMember(ctx context.Context, etcdHost *hosts.Host, etcdHosts []*hosts.Host, localConnDialerFactory hosts.DialerFactory,
+	k8sVersion string, cert, key []byte) (bool, error) {
 	var listErr error
 	peerURL := fmt.Sprintf("https://%s:2380", etcdHost.InternalAddress)
 	for _, host := range etcdHosts {
 		if host.Address == etcdHost.Address {
 			continue
 		}
-		etcdClient, err := getEtcdClient(ctx, host, localConnDialerFactory, cert, key)
+		if etcdClientV3Range(k8sVersion) {
+			etcdClient, err := getEtcdClientV3(ctx, host, localConnDialerFactory, cert, key)
 			if err != nil {
 				listErr = errors.Wrapf(err, "Failed to create etcd client for host [%s]", host.Address)
 				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
 				continue
 			}
-		memAPI := etcdclient.NewMembersAPI(etcdClient)
+			members, err := etcdClient.MemberList(ctx)
+			if err != nil {
+				listErr = errors.Wrapf(err, "Failed to create etcd client for host [%s]", host.Address)
+				logrus.Debugf("Failed to list etcd cluster members [%s]: %v", etcdHost.Address, err)
+				continue
+			}
+			for _, member := range members.Members {
+				if strings.Contains(member.PeerURLs[0], peerURL) {
+					logrus.Infof("[etcd] member [%s] is already part of the etcd cluster", etcdHost.Address)
+					return true, nil
+				}
+			}
+		} else {
+			etcdClient, err := getEtcdClientV2(ctx, host, localConnDialerFactory, cert, key)
+			if err != nil {
+				listErr = errors.Wrapf(err, "Failed to create etcd client for host [%s]", host.Address)
+				logrus.Debugf("Failed to create etcd client for host [%s]: %v", host.Address, err)
+				continue
+			}
+			memAPI := etcdclientv2.NewMembersAPI(etcdClient)
 			members, err := memAPI.List(ctx)
 			if err != nil {
 				listErr = errors.Wrapf(err, "Failed to create etcd client for host [%s]", host.Address)
@@ -304,6 +377,8 @@ func IsEtcdMember(ctx context.Context, etcdHost *hosts.Host, etcdHosts []*hosts.
 					return true, nil
 				}
 			}
+		}
+
 		// reset the list of errors to handle new hosts
 		listErr = nil
 		break

services/etcd_util.go

@@ -11,12 +11,14 @@ import (
 	"strings"
 	"time"
 
-	etcdclient "github.com/coreos/etcd/client"
 	"github.com/rancher/rke/hosts"
 	"github.com/sirupsen/logrus"
+	etcdclientv2 "go.etcd.io/etcd/client/v2"
+	etcdclientv3 "go.etcd.io/etcd/client/v3"
+	"google.golang.org/grpc"
 )
 
-func getEtcdClient(ctx context.Context, etcdHost *hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte) (etcdclient.Client, error) {
+func getEtcdClientV2(ctx context.Context, etcdHost *hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte) (etcdclientv2.Client, error) {
 	dialer, err := getEtcdDialer(localConnDialerFactory, etcdHost)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create a dialer for host [%s]: %v", etcdHost.Address, err)
@@ -26,18 +28,44 @@ func getEtcdClient(ctx context.Context, etcdHost *hosts.Host, localConnDialerFac
 		return nil, err
 	}
 
-	var DefaultEtcdTransport etcdclient.CancelableTransport = &http.Transport{
+	var defaultEtcdTransport etcdclientv2.CancelableTransport = &http.Transport{
 		Dial:                dialer,
 		TLSClientConfig:     tlsConfig,
 		TLSHandshakeTimeout: 10 * time.Second,
 	}
 
-	cfg := etcdclient.Config{
+	cfg := etcdclientv2.Config{
 		Endpoints: []string{"https://" + etcdHost.InternalAddress + ":2379"},
-		Transport: DefaultEtcdTransport,
+		Transport: defaultEtcdTransport,
 	}
 
-	return etcdclient.New(cfg)
+	return etcdclientv2.New(cfg)
+}
+
+func getEtcdClientV3(ctx context.Context, etcdHost *hosts.Host, localConnDialerFactory hosts.DialerFactory, cert, key []byte) (*etcdclientv3.Client, error) {
+	dialer, err := getEtcdDialer(localConnDialerFactory, etcdHost)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create a dialer for host [%s]: %v", etcdHost.Address, err)
+	}
+	tlsConfig, err := getEtcdTLSConfig(cert, key)
+	if err != nil {
+		return nil, err
+	}
+
+	cfg := etcdclientv3.Config{
+		Endpoints:   []string{"https://" + etcdHost.InternalAddress + ":2379"},
+		TLS:         tlsConfig,
+		DialOptions: []grpc.DialOption{grpc.WithContextDialer(wrapper(dialer))},
+	}
+
+	return etcdclientv3.New(cfg)
+
+}
+
+func wrapper(f func(network, address string) (net.Conn, error)) func(context.Context, string) (net.Conn, error) {
+	return func(_ context.Context, address string) (net.Conn, error) {
+		return f("tcp", address)
+	}
 }
 
 func isEtcdHealthy(localConnDialerFactory hosts.DialerFactory, host *hosts.Host, cert, key []byte, url string) error {