establish SSH connection when adding a new machine

internal/cli/cli.go

@@ -10,6 +10,7 @@ import (
 	"uncloud/internal/cli/config"
 	"uncloud/internal/machine/api/pb"
 	"uncloud/internal/secret"
+	"uncloud/internal/sshexec"
 )
 
 const defaultClusterName = "default"
@@ -196,9 +197,52 @@ func (cli *CLI) AddMachine(ctx context.Context, remoteMachine RemoteMachine, clu
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}
+	defer func() {
+		_ = c.Close()
+	}()
+
+	sshClient, err := sshexec.Connect(remoteMachine.User, remoteMachine.Host, remoteMachine.Port, remoteMachine.KeyPath)
+	if err != nil {
+		return fmt.Errorf(
+			"SSH login to remote machine %s: %w",
+			config.NewSSHDestination(remoteMachine.User, remoteMachine.Host, remoteMachine.Port), err,
+		)
+	}
+	machineExec := sshexec.NewRemote(sshClient)
+
+	// TODO: Check if the machine is already provisioned using machineClient and ask the user to reset it first.
+	//conn := connector.NewSSHConnectorFromClient(sshClient)
+	//machineClient, err := client.New(ctx, conn)
+	//if err != nil {
+	//	return fmt.Errorf("connect to remote machine API: %w", err)
+	//}
+
+	// TODO: Download and install the latest uncloudd binary by running the install shell script from GitHub.
+	//  For now upload the binary using scp manually.
+	if _, err = machineExec.Run(ctx, "which uncloudd"); err != nil {
+		return fmt.Errorf("uncloudd binary not found on the remote machine: %w", err)
+	}
+
+	//req := &pb.AddMachineRequest{
+	//	Name: machineName,
+	//	Network: &pb.NetworkConfig{
+	//
+	//	}
+	//}
+	//resp, err := c.AddMachine(ctx, req)
+	//if err != nil {
+	//	return fmt.Errorf("add machine to cluster: %w", err)
+	//}
+
+	// TODO:
+	// --1. Establish a client connection to the remote machine.
+	// --2. Check if the machine is already provisioned and ask the user to reset it first.
+	// --3. Download and install the latest uncloudd binary by running the install shell script from GitHub.
+	// 4. Request token from the remote machine.
+	// 5. Add the machine to the cluster using its token and receive a configuration token.
+	// 6. Request the machine to join the cluster using the configuration token.
+	// 7. Save the machine's SSH connection details in the cluster config.
 
-	fmt.Println("Adding machine to cluster...", c)
-	// TODO
 	//name, connCfg, err := c.AddMachine(ctx, machineName, user, host, port, sshKeyPath)
 	//if err != nil {
 	//	return fmt.Errorf("add machine to cluster %q: %w", cluster.Name(), err)

internal/cli/client/cluster.go

@@ -2,7 +2,6 @@ package client
 
 import (
 	"context"
-	"crypto/ed25519"
 	"errors"
 	"fmt"
 	"google.golang.org/grpc"
@@ -297,11 +296,3 @@ func (c *ClusterClient) registerNewMachine(
 	}
 	return c.client.AddMachine(ctx, req)
 }
-
-func privateKeyFromSecret(s secret.Secret) (ed25519.PrivateKey, error) {
-	// Cluster secret in the config is a hex-encoded private key seed.
-	if len(s) != ed25519.SeedSize {
-		return nil, fmt.Errorf("invalid cluster secret length")
-	}
-	return ed25519.NewKeyFromSeed(s), nil
-}

internal/cli/client/connector/ssh.go

@@ -41,13 +41,23 @@ func NewSSHConnector(cfg *SSHConnectorConfig) *SSHConnector {
 	return c
 }
 
+func NewSSHConnectorFromClient(client *ssh.Client) *SSHConnector {
+	return &SSHConnector{client: client}
+}
+
 // TODO: handle context cancelation.
 func (c *SSHConnector) Connect(ctx context.Context) (*grpc.ClientConn, error) {
+	if c.client == nil {
+		// Establish an SSH connection if the SSH client is not provided.
+		if c.config == (SSHConnectorConfig{}) {
+			return nil, fmt.Errorf("SSH connector not configured")
+		}
 		var err error
 		c.client, err = sshexec.Connect(c.config.User, c.config.Host, c.config.Port, c.config.KeyPath)
 		if err != nil {
 			return nil, fmt.Errorf("SSH login to %s@%s:%d: %w", c.config.User, c.config.Host, c.config.Port, err)
 		}
+	}
 
 	conn, err := grpc.NewClient(
 		"unix://"+c.config.APISockPath,

internal/cli/config/connection.go

@@ -18,6 +18,8 @@ type MachineConnection struct {
 	PublicKey secret.Secret  `toml:"public_key,omitempty"`
 }
 
+// SSHDestination represents an SSH destination string in the canonical form of "user@host:port".
+// The default user "root" and port 22 can be omitted.
 type SSHDestination string
 
 func NewSSHDestination(user, host string, port int) SSHDestination {
@@ -37,10 +39,16 @@ func (d SSHDestination) Parse() (user string, host string, port int, err error)
 	if strings.Contains(host, "@") {
 		user, host, _ = strings.Cut(host, "@")
 	}
+	if user == "" {
+		user = DefaultSSHUser
+	}
 	h, p, sErr := net.SplitHostPort(host)
 	if sErr == nil {
 		host = h
 		port, err = strconv.Atoi(p)
 	}
+	if port == 0 {
+		port = DefaultSSHPort
+	}
 	return
 }