feat: Add config-ssh command (#735)

* feat: Add config-ssh command

Closes #254 and #499.

* Fix Windows support

cli/ssh.go

@@ -2,18 +2,28 @@ package cli
 
 import (
 	"context"
+	"io"
+	"net"
+	"os"
+	"time"
 
+	"github.com/mattn/go-isatty"
 	"github.com/pion/webrtc/v3"
 	"github.com/spf13/cobra"
 	gossh "golang.org/x/crypto/ssh"
 	"golang.org/x/xerrors"
 
+	"github.com/coder/coder/cli/cliflag"
 	"github.com/coder/coder/cli/cliui"
 	"github.com/coder/coder/coderd/database"
 	"github.com/coder/coder/codersdk"
+	"golang.org/x/crypto/ssh/terminal"
 )
 
 func ssh() *cobra.Command {
+	var (
+		stdio bool
+	)
 	cmd := &cobra.Command{
 		Use: "ssh <workspace> [resource]",
 		RunE: func(cmd *cobra.Command, args []string) error {
@@ -25,8 +35,11 @@ func ssh() *cobra.Command {
 			if err != nil {
 				return err
 			}
+			if workspace.LatestBuild.Transition != database.WorkspaceTransitionStart {
+				return xerrors.New("workspace must be in start transition to ssh")
+			}
 			if workspace.LatestBuild.Job.CompletedAt == nil {
-				err = cliui.WorkspaceBuild(cmd, client, workspace.LatestBuild.ID, workspace.CreatedAt)
+				err = cliui.WorkspaceBuild(cmd.Context(), cmd.ErrOrStderr(), client, workspace.LatestBuild.ID, workspace.CreatedAt)
 				if err != nil {
 					return err
 				}
@@ -67,7 +80,9 @@ func ssh() *cobra.Command {
 				}
 				return xerrors.Errorf("no sshable agent with address %q: %+v", resourceAddress, resourceKeys)
 			}
-			err = cliui.Agent(cmd, cliui.AgentOptions{
+			// OpenSSH passes stderr directly to the calling TTY.
+			// This is required in "stdio" mode so a connecting indicator can be displayed.
+			err = cliui.Agent(cmd.Context(), cmd.ErrOrStderr(), cliui.AgentOptions{
 				WorkspaceName: workspace.Name,
 				Fetch: func(ctx context.Context) (codersdk.WorkspaceResource, error) {
 					return client.WorkspaceResource(ctx, resource.ID)
@@ -84,6 +99,17 @@ func ssh() *cobra.Command {
 				return err
 			}
 			defer conn.Close()
+			if stdio {
+				rawSSH, err := conn.SSH()
+				if err != nil {
+					return err
+				}
+				go func() {
+					_, _ = io.Copy(cmd.OutOrStdout(), rawSSH)
+				}()
+				_, _ = io.Copy(rawSSH, cmd.InOrStdin())
+				return nil
+			}
 			sshClient, err := conn.SSHClient()
 			if err != nil {
 				return err
@@ -94,9 +120,17 @@ func ssh() *cobra.Command {
 				return err
 			}
 
-			err = sshSession.RequestPty("xterm-256color", 128, 128, gossh.TerminalModes{
-				gossh.OCRNL: 1,
-			})
+			if isatty.IsTerminal(os.Stdout.Fd()) {
+				state, err := terminal.MakeRaw(int(os.Stdin.Fd()))
+				if err != nil {
+					return err
+				}
+				defer func() {
+					_ = terminal.Restore(int(os.Stdin.Fd()), state)
+				}()
+			}
+
+			err = sshSession.RequestPty("xterm-256color", 128, 128, gossh.TerminalModes{})
 			if err != nil {
 				return err
 			}
@@ -115,6 +149,36 @@ func ssh() *cobra.Command {
 			return nil
 		},
 	}
+	cliflag.BoolVarP(cmd.Flags(), &stdio, "stdio", "", "CODER_SSH_STDIO", false, "Specifies whether to emit SSH output over stdin/stdout.")
 
 	return cmd
 }
+
+type stdioConn struct {
+	io.Reader
+	io.Writer
+}
+
+func (*stdioConn) Close() (err error) {
+	return nil
+}
+
+func (*stdioConn) LocalAddr() net.Addr {
+	return nil
+}
+
+func (*stdioConn) RemoteAddr() net.Addr {
+	return nil
+}
+
+func (*stdioConn) SetDeadline(_ time.Time) error {
+	return nil
+}
+
+func (*stdioConn) SetReadDeadline(_ time.Time) error {
+	return nil
+}
+
+func (*stdioConn) SetWriteDeadline(_ time.Time) error {
+	return nil
+}