feat: add commands to manage/query etcd cluster

Used already existing protobufs for that.

Commands:
`talosctl etcd members -n <node>`
`talosctl etcd leave -n <node>`
`talosctl etcd forfeit-leadership -n <node>`

Signed-off-by: Artem Chernyshev <artem.0xD2@gmail.com>

api/machine/machine.proto

@@ -724,7 +724,9 @@ message EtcdForfeitLeadershipResponse {
   repeated EtcdForfeitLeadership messages = 1;
 }
 
-message EtcdMemberListRequest {}
+message EtcdMemberListRequest {
+  bool query_local = 1;
+}
 message EtcdMemberList {
   common.Metadata metadata = 1;
   repeated string members = 2;

cmd/talosctl/cmd/talos/etcd.go

@@ -0,0 +1,105 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package talos
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+	"text/tabwriter"
+
+	"github.com/spf13/cobra"
+
+	"github.com/talos-systems/talos/pkg/machinery/api/machine"
+	"github.com/talos-systems/talos/pkg/machinery/client"
+)
+
+// etcdCmd represents the etcd command.
+var etcdCmd = &cobra.Command{
+	Use:   "etcd",
+	Short: "Manage etcd",
+	Long:  ``,
+}
+
+var etcdLeaveCmd = &cobra.Command{
+	Use:   "leave",
+	Short: "Tell nodes to leave etcd cluster",
+	Long:  ``,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return WithClient(func(ctx context.Context, c *client.Client) error {
+			_, err := c.MachineClient.EtcdLeaveCluster(ctx, &machine.EtcdLeaveClusterRequest{})
+
+			return err
+		})
+	},
+}
+
+var etcdForfeitLeadershipCmd = &cobra.Command{
+	Use:   "forfeit-leadership",
+	Short: "Tell node to forfeit etcd cluster leadership",
+	Long:  ``,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return WithClient(func(ctx context.Context, c *client.Client) error {
+			_, err := c.MachineClient.EtcdForfeitLeadership(ctx, &machine.EtcdForfeitLeadershipRequest{})
+
+			return err
+		})
+	},
+}
+
+var etcdMemberListCmd = &cobra.Command{
+	Use:   "members",
+	Short: "Get the list of etcd cluster members",
+	Long:  ``,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		return WithClient(func(ctx context.Context, c *client.Client) error {
+			response, err := c.MachineClient.EtcdMemberList(ctx, &machine.EtcdMemberListRequest{
+				QueryLocal: true,
+			})
+			if err != nil {
+				return fmt.Errorf("error getting members: %w", err)
+			}
+
+			w := tabwriter.NewWriter(os.Stdout, 0, 0, 3, ' ', 0)
+			node := ""
+			pattern := "%s\t"
+
+			for i, message := range response.Messages {
+				if message.Metadata != nil && message.Metadata.Hostname != "" {
+					node = message.Metadata.Hostname
+				}
+
+				if len(message.Members) == 0 {
+					continue
+				}
+
+				if i == 0 {
+					if node != "" {
+						fmt.Fprintln(w, "NODE\tMEMBERS")
+						pattern = "%s\t%s\n"
+					} else {
+						fmt.Fprintln(w, "MEMBERS")
+					}
+				}
+
+				args := []interface{}{strings.Join(message.Members, ",")}
+				if node != "" {
+					args = append([]interface{}{node}, args...)
+				}
+
+				fmt.Fprintf(w, pattern, args...)
+
+			}
+
+			return w.Flush()
+		})
+	},
+}
+
+func init() {
+	etcdCmd.AddCommand(etcdLeaveCmd, etcdForfeitLeadershipCmd, etcdMemberListCmd)
+	addCommand(etcdCmd)
+}

internal/app/machined/internal/server/v1alpha1/v1alpha1_server.go

@@ -1610,7 +1610,14 @@ func (s *Server) Memory(ctx context.Context, in *empty.Empty) (reply *machine.Me
 
 // EtcdMemberList implements the machine.MachineServer interface.
 func (s *Server) EtcdMemberList(ctx context.Context, in *machine.EtcdMemberListRequest) (reply *machine.EtcdMemberListResponse, err error) {
-	client, err := etcd.NewClientFromControlPlaneIPs(ctx, s.Controller.Runtime().Config().Cluster().CA(), s.Controller.Runtime().Config().Cluster().Endpoint())
+	var client *etcd.Client
+
+	if in.QueryLocal {
+		client, err = etcd.NewClient([]string{"127.0.0.1:2379"})
+	} else {
+		client, err = etcd.NewClientFromControlPlaneIPs(ctx, s.Controller.Runtime().Config().Cluster().CA(), s.Controller.Runtime().Config().Cluster().Endpoint())
+	}
+
 	if err != nil {
 		return nil, err
 	}

internal/integration/cli/etcd.go

@@ -0,0 +1,38 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+// +build integration_cli
+
+package cli
+
+import (
+	"github.com/talos-systems/talos/internal/integration/base"
+	"github.com/talos-systems/talos/pkg/machinery/config/types/v1alpha1/machine"
+)
+
+// EtcdSuite verifies etcd command.
+type EtcdSuite struct {
+	base.CLISuite
+}
+
+// SuiteName ...
+func (suite *EtcdSuite) SuiteName() string {
+	return "cli.EtcdSuite"
+}
+
+// TestMembers etcd members should have some output.
+func (suite *EtcdSuite) TestMembers() {
+	suite.RunCLI([]string{"etcd", "members", "--nodes", suite.RandomDiscoveredNode(machine.TypeControlPlane)}) // default checks for stdout not empty
+}
+
+// TestForfeitLeadership etcd forfeit-leadership check.
+func (suite *EtcdSuite) TestForfeitLeadership() {
+	suite.RunCLI([]string{"etcd", "forfeit-leadership", "--nodes", suite.RandomDiscoveredNode(machine.TypeControlPlane)},
+		base.StdoutEmpty(),
+	)
+}
+
+func init() {
+	allSuites = append(allSuites, new(EtcdSuite))
+}