-
Notifications
You must be signed in to change notification settings - Fork 4.7k
/
terminal.go
122 lines (99 loc) · 2.97 KB
/
terminal.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
package util
import (
"bufio"
"fmt"
"io"
"os"
"strings"
"github.com/docker/docker/pkg/term"
"github.com/golang/glog"
kterm "k8s.io/kubernetes/pkg/util/term"
)
// PromptForString takes an io.Reader and prompts for user input if it's a terminal, returning the result.
func PromptForString(r io.Reader, w io.Writer, format string, a ...interface{}) string {
if w == nil {
w = os.Stdout
}
fmt.Fprintf(w, format, a...)
return readInput(r)
}
// PromptForPasswordString prompts for user input by disabling echo in terminal, useful for password prompt.
func PromptForPasswordString(r io.Reader, w io.Writer, format string, a ...interface{}) string {
if w == nil {
w = os.Stdout
}
if file, ok := r.(*os.File); ok {
inFd := file.Fd()
if term.IsTerminal(inFd) {
oldState, err := term.SaveState(inFd)
if err != nil {
glog.V(3).Infof("Unable to save terminal state")
return PromptForString(r, w, format, a...)
}
fmt.Fprintf(w, format, a...)
term.DisableEcho(inFd, oldState)
input := readInput(r)
defer term.RestoreTerminal(inFd, oldState)
fmt.Fprintf(w, "\n")
return input
}
glog.V(3).Infof("Stdin is not a terminal")
return PromptForString(r, w, format, a...)
}
return PromptForString(r, w, format, a...)
}
// PromptForBool prompts for user input of a boolean value. The accepted values are:
// yes, y, true, t, 1 (not case sensitive)
// no, n, false, f, 0 (not case sensitive)
// A valid answer is mandatory so it will keep asking until an answer is provided.
func PromptForBool(r io.Reader, w io.Writer, format string, a ...interface{}) bool {
if w == nil {
w = os.Stdout
}
str := PromptForString(r, w, format, a...)
switch strings.ToLower(str) {
case "1", "t", "true", "y", "yes":
return true
case "0", "f", "false", "n", "no":
return false
}
fmt.Println("Please enter 'yes' or 'no'.")
return PromptForBool(r, w, format, a...)
}
// PromptForStringWithDefault prompts for user input but take a default in case nothing is provided.
func PromptForStringWithDefault(r io.Reader, w io.Writer, def string, format string, a ...interface{}) string {
if w == nil {
w = os.Stdout
}
s := PromptForString(r, w, format, a...)
if len(s) == 0 {
return def
}
return s
}
func readInput(r io.Reader) string {
if kterm.IsTerminal(r) {
return readInputFromTerminal(r)
}
return readInputFromReader(r)
}
func readInputFromTerminal(r io.Reader) string {
reader := bufio.NewReader(r)
result, _ := reader.ReadString('\n')
return strings.TrimRight(result, "\r\n")
}
func readInputFromReader(r io.Reader) string {
var result string
fmt.Fscan(r, &result)
return result
}
// IsTerminalReader returns whether the passed io.Reader is a terminal or not
func IsTerminalReader(r io.Reader) bool {
file, ok := r.(*os.File)
return ok && term.IsTerminal(file.Fd())
}
// IsTerminalWriter returns whether the passed io.Writer is a terminal or not
func IsTerminalWriter(w io.Writer) bool {
file, ok := w.(*os.File)
return ok && term.IsTerminal(file.Fd())
}