write unit test

communicator/ssh/keyboard_interactive.go

@@ -1,14 +1,15 @@
 package ssh
 
 import (
+	"io"
 	"log"
-	"os"
 
 	"golang.org/x/crypto/ssh"
 	"golang.org/x/crypto/ssh/terminal"
 )
 
-func KeyboardInteractive() ssh.KeyboardInteractiveChallenge {
+func KeyboardInteractive(c io.ReadWriter) ssh.KeyboardInteractiveChallenge {
+	t := terminal.NewTerminal(c, "")
 	return func(user, instruction string, questions []string, echos []bool) ([]string, error) {
 		if len(questions) == 0 {
 			return []string{}, nil
@@ -21,18 +22,7 @@ func KeyboardInteractive() ssh.KeyboardInteractiveChallenge {
 		}
 		answers := make([]string, len(questions))
 		for i := range questions {
-			var fd int
-			if terminal.IsTerminal(int(os.Stdin.Fd())) {
-				fd = int(os.Stdin.Fd())
-			} else {
-				tty, err := os.Open("/dev/tty")
-				if err != nil {
-					return nil, err
-				}
-				defer tty.Close()
-				fd = int(tty.Fd())
-			}
-			s, err := terminal.ReadPassword(fd)
+			s, err := t.ReadPassword("")
 			if err != nil {
 				return nil, err
 			}

communicator/ssh/keyboard_interactive_test.go

@@ -0,0 +1,89 @@
+package ssh
+
+import (
+	"io"
+	"log"
+	"reflect"
+	"testing"
+)
+
+type MockTerminal struct {
+	toSend       []byte
+	bytesPerRead int
+	received     []byte
+}
+
+func (c *MockTerminal) Read(data []byte) (n int, err error) {
+	n = len(data)
+	if n == 0 {
+		return
+	}
+	if n > len(c.toSend) {
+		n = len(c.toSend)
+	}
+	if n == 0 {
+		return 0, io.EOF
+	}
+	if c.bytesPerRead > 0 && n > c.bytesPerRead {
+		n = c.bytesPerRead
+	}
+	copy(data, c.toSend[:n])
+	c.toSend = c.toSend[n:]
+	return
+}
+
+func (c *MockTerminal) Write(data []byte) (n int, err error) {
+	c.received = append(c.received, data...)
+	return len(data), nil
+}
+
+func TestKeyboardInteractive(t *testing.T) {
+	type args struct {
+		user        string
+		instruction string
+		questions   []string
+		echos       []bool
+	}
+	tests := []struct {
+		name    string
+		args    args
+		want    []string
+		wantErr bool
+	}{
+		{
+			name: "questions are none",
+			args: args{
+				questions: []string{},
+			},
+			want:    []string{},
+			wantErr: false,
+		},
+		{
+			name: "input answer interactive",
+			args: args{
+				questions: []string{"this is question"},
+			},
+			want:    []string{"xxxx"},
+			wantErr: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			c := &MockTerminal{
+				toSend:       []byte("xxxx\r\x1b[A\r"),
+				bytesPerRead: 1,
+			}
+			f := KeyboardInteractive(c)
+			got, err := f(tt.args.user, tt.args.instruction, tt.args.questions, tt.args.echos)
+
+			if (err != nil) != tt.wantErr {
+				t.Errorf("KeyboardInteractive error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("KeyboardInteractive = %v, want %v", got, tt.want)
+			}
+			log.Printf("finish")
+		})
+	}
+}

helper/communicator/step_connect_ssh.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"golang.org/x/crypto/ssh/terminal"
+	"io"
 	"log"
 	"net"
 	"os"
@@ -247,7 +249,18 @@ func sshBastionConfig(config *Config) (*gossh.ClientConfig, error) {
 	auth := make([]gossh.AuthMethod, 0, 2)
 
 	if config.SSHBastionInteractive {
-		auth = append(auth, gossh.KeyboardInteractive(ssh.KeyboardInteractive()))
+		var c io.ReadWriteCloser
+		if terminal.IsTerminal(int(os.Stdin.Fd())) {
+			c = os.Stdin
+		} else {
+			tty, err := os.Open("/dev/tty")
+			if err != nil {
+				return nil, err
+			}
+			defer tty.Close()
+			c = tty
+		}
+		auth = append(auth, gossh.KeyboardInteractive(ssh.KeyboardInteractive(c)))
 	}
 
 	if config.SSHBastionPassword != "" {