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
|
package adapter
import (
"context"
"os"
gosignal "os/signal"
"github.com/docker/docker/pkg/signal"
"github.com/docker/docker/pkg/term"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"k8s.io/client-go/tools/remotecommand"
)
// RawTtyFormatter ...
type RawTtyFormatter struct {
}
// getResize returns a TerminalSize command matching stdin's current
// size on success, and nil on errors.
func getResize() *remotecommand.TerminalSize {
winsize, err := term.GetWinsize(os.Stdin.Fd())
if err != nil {
logrus.Warnf("Could not get terminal size %v", err)
return nil
}
return &remotecommand.TerminalSize{
Width: winsize.Width,
Height: winsize.Height,
}
}
// Helper for prepareAttach - set up a goroutine to generate terminal resize events
func resizeTty(ctx context.Context, resize chan remotecommand.TerminalSize) {
sigchan := make(chan os.Signal, 1)
gosignal.Notify(sigchan, signal.SIGWINCH)
go func() {
defer close(resize)
// Update the terminal size immediately without waiting
// for a SIGWINCH to get the correct initial size.
resizeEvent := getResize()
for {
if resizeEvent == nil {
select {
case <-ctx.Done():
return
case <-sigchan:
resizeEvent = getResize()
}
} else {
select {
case <-ctx.Done():
return
case <-sigchan:
resizeEvent = getResize()
case resize <- *resizeEvent:
resizeEvent = nil
}
}
}
}()
}
func restoreTerminal(state *term.State) error {
logrus.SetFormatter(&logrus.TextFormatter{})
return term.RestoreTerminal(os.Stdin.Fd(), state)
}
// Format ...
func (f *RawTtyFormatter) Format(entry *logrus.Entry) ([]byte, error) {
textFormatter := logrus.TextFormatter{}
bytes, err := textFormatter.Format(entry)
if err == nil {
bytes = append(bytes, '\r')
}
return bytes, err
}
func handleTerminalAttach(ctx context.Context, resize chan remotecommand.TerminalSize) (context.CancelFunc, *term.State, error) {
logrus.Debugf("Handling terminal attach")
subCtx, cancel := context.WithCancel(ctx)
resizeTty(subCtx, resize)
oldTermState, err := term.SaveState(os.Stdin.Fd())
if err != nil {
// allow caller to not have to do any cleaning up if we error here
cancel()
return nil, nil, errors.Wrapf(err, "unable to save terminal state")
}
logrus.SetFormatter(&RawTtyFormatter{})
if _, err := term.SetRawTerminal(os.Stdin.Fd()); err != nil {
return cancel, nil, err
}
return cancel, oldTermState, nil
}
|