From 6e37a72295e41b5311c6e3884e91314f8b347226 Mon Sep 17 00:00:00 2001
From: Robin Cernin <cerninr@gmail.com>
Date: Wed, 10 Mar 2021 08:43:52 +1000
Subject: [PATCH] etcdctl: allow move-leader to connect to multiple endpoints
 with TLS

Re-opening closed PR #11775 which was originaly authored by benmoss.

The mustClientForCmd function is responsible for parsing environment
variables and flags into configuration data. A change was made in #9382
to call Fatal if a flag is provided multiple times. This means that we
cannot call the mustClientForCmd function more than once,
since it will think that flags parsed the first time are now
being redefined and error out.

Some people have commented about this in #8380 but I don't think
there's an open issue for it.
---
 etcdctl/ctlv3/command/move_leader_command.go |  4 +--
 tests/e2e/ctl_v3_move_leader_test.go         | 34 ++++++++++++--------
 2 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/etcdctl/ctlv3/command/move_leader_command.go b/etcdctl/ctlv3/command/move_leader_command.go
index 1aee99b24445..a07e095b5e1a 100644
--- a/etcdctl/ctlv3/command/move_leader_command.go
+++ b/etcdctl/ctlv3/command/move_leader_command.go
@@ -42,7 +42,8 @@ func transferLeadershipCommandFunc(cmd *cobra.Command, args []string) {
 		ExitWithError(ExitBadArgs, err)
 	}
 
-	c := mustClientFromCmd(cmd)
+	cfg := clientConfigFromCmd(cmd)
+	c := cfg.mustClient()
 	eps := c.Endpoints()
 	c.Close()
 
@@ -52,7 +53,6 @@ func transferLeadershipCommandFunc(cmd *cobra.Command, args []string) {
 	var leaderCli *clientv3.Client
 	var leaderID uint64
 	for _, ep := range eps {
-		cfg := clientConfigFromCmd(cmd)
 		cfg.endpoints = []string{ep}
 		cli := cfg.mustClient()
 		resp, serr := cli.Status(ctx, ep)
diff --git a/tests/e2e/ctl_v3_move_leader_test.go b/tests/e2e/ctl_v3_move_leader_test.go
index 507ca4c16213..8b1d6fd55b27 100644
--- a/tests/e2e/ctl_v3_move_leader_test.go
+++ b/tests/e2e/ctl_v3_move_leader_test.go
@@ -29,25 +29,36 @@ import (
 )
 
 func TestCtlV3MoveLeaderSecure(t *testing.T) {
-	testCtlV3MoveLeader(t, *newConfigTLS())
+	testCtlV3MoveLeader(t, withCfg(*newConfigTLS()))
+	testCtlV3MoveLeader(t, withCfg(*newConfigTLS()), withFlagByEnv())
 }
 
 func TestCtlV3MoveLeaderInsecure(t *testing.T) {
-	testCtlV3MoveLeader(t, *newConfigNoTLS())
+	testCtlV3MoveLeader(t, withCfg(*newConfigNoTLS()))
+	testCtlV3MoveLeader(t, withCfg(*newConfigNoTLS()), withFlagByEnv())
 }
 
-func testCtlV3MoveLeader(t *testing.T, cfg etcdProcessClusterConfig) {
+func testCtlV3MoveLeader(t *testing.T, opts ...ctlOption) {
 	defer testutil.AfterTest(t)
 
-	epc := setupEtcdctlTest(t, &cfg, true)
+	ret := ctlCtx{
+		t:           t,
+		cfg:         *newConfigAutoTLS(),
+		dialTimeout: 7 * time.Second,
+	}
+	ret.applyOpts(opts)
+
+	epc := setupEtcdctlTest(t, &ret.cfg, true)
+	ret.epc = epc
+
 	defer func() {
-		if errC := epc.Close(); errC != nil {
+		if errC := ret.epc.Close(); errC != nil {
 			t.Fatalf("error closing etcd processes (%v)", errC)
 		}
 	}()
 
 	var tcfg *tls.Config
-	if cfg.clientTLS == clientTLS {
+	if ret.cfg.clientTLS == clientTLS {
 		tinfo := transport.TLSInfo{
 			CertFile:      certPath,
 			KeyFile:       privateKeyPath,
@@ -90,26 +101,21 @@ func testCtlV3MoveLeader(t *testing.T, cfg etcdProcessClusterConfig) {
 
 	os.Setenv("ETCDCTL_API", "3")
 	defer os.Unsetenv("ETCDCTL_API")
-	cx := ctlCtx{
-		t:           t,
-		cfg:         *newConfigNoTLS(),
-		dialTimeout: 7 * time.Second,
-		epc:         epc,
-	}
 
 	tests := []struct {
 		prefixes []string
 		expect   string
 	}{
 		{ // request to non-leader
-			cx.prefixArgs([]string{cx.epc.EndpointsV3()[(leadIdx+1)%3]}),
+			ret.prefixArgs([]string{ret.epc.EndpointsV3()[(leadIdx+1)%3]}),
 			"no leader endpoint given at ",
 		},
 		{ // request to leader
-			cx.prefixArgs([]string{cx.epc.EndpointsV3()[leadIdx]}),
+			ret.prefixArgs([]string{ret.epc.EndpointsV3()[leadIdx]}),
 			fmt.Sprintf("Leadership transferred from %s to %s", types.ID(leaderID), types.ID(transferee)),
 		},
 	}
+
 	for i, tc := range tests {
 		cmdArgs := append(tc.prefixes, "move-leader", types.ID(transferee).String())
 		if err := spawnWithExpect(cmdArgs, tc.expect); err != nil {