aboutsummaryrefslogtreecommitdiff
path: root/cmd/podman/save.go
blob: 85a8c79305ac99f833a2b0dda82bd7ba36e2d3f9 (plain)
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
123
124
125
126
127
128
129
package main

import (
	"io"
	"os"
	"strings"

	"github.com/containers/image/manifest"
	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
	"github.com/pkg/errors"
	"github.com/projectatomic/libpod/libpod"
	"github.com/sirupsen/logrus"
	"github.com/urfave/cli"
)

const (
	ociManifestDir  = "oci-dir"
	v2s2ManifestDir = "docker-dir"
)

var (
	saveFlags = []cli.Flag{
		cli.BoolFlag{
			Name:  "compress",
			Usage: "compress tarball image layers when saving to a directory using the 'dir' transport. (default is same compression type as source)",
		},
		cli.StringFlag{
			Name:  "output, o",
			Usage: "Write to a file, default is STDOUT",
			Value: "/dev/stdout",
		},
		cli.BoolFlag{
			Name:  "quiet, q",
			Usage: "Suppress the output",
		},
		cli.StringFlag{
			Name:  "format",
			Usage: "Save image to oci-archive, oci-dir (directory with oci manifest type), docker-dir (directory with v2s2 manifest type)",
		},
	}
	saveDescription = `
	Save an image to docker-archive or oci-archive on the local machine.
	Default is docker-archive`

	saveCommand = cli.Command{
		Name:        "save",
		Usage:       "Save image to an archive",
		Description: saveDescription,
		Flags:       saveFlags,
		Action:      saveCmd,
		ArgsUsage:   "",
	}
)

// saveCmd saves the image to either docker-archive or oci
func saveCmd(c *cli.Context) error {
	args := c.Args()
	if len(args) == 0 {
		return errors.Errorf("need at least 1 argument")
	}
	if err := validateFlags(c, saveFlags); err != nil {
		return err
	}

	runtime, err := getRuntime(c)
	if err != nil {
		return errors.Wrapf(err, "could not create runtime")
	}
	defer runtime.Shutdown(false)

	if c.IsSet("compress") && (c.String("format") != ociManifestDir && c.String("format") != v2s2ManifestDir && c.String("format") == "") {
		return errors.Errorf("--compress can only be set when --format is either 'oci-dir' or 'docker-dir'")
	}

	var writer io.Writer
	if !c.Bool("quiet") {
		writer = os.Stdout
	}

	output := c.String("output")
	if output == "/dev/stdout" {
		fi := os.Stdout
		if logrus.IsTerminal(fi) {
			return errors.Errorf("refusing to save to terminal. Use -o flag or redirect")
		}
	}

	var dst, manifestType string
	switch c.String("format") {
	case libpod.OCIArchive:
		dst = libpod.OCIArchive + ":" + output
	case "oci-dir":
		dst = libpod.DirTransport + ":" + output
		manifestType = imgspecv1.MediaTypeImageManifest
	case "docker-dir":
		dst = libpod.DirTransport + ":" + output
		manifestType = manifest.DockerV2Schema2MediaType
	case libpod.DockerArchive:
		fallthrough
	case "":
		dst = libpod.DockerArchive + ":" + output
	default:
		return errors.Errorf("unknown format option %q", c.String("format"))
	}

	saveOpts := libpod.CopyOptions{
		SignaturePolicyPath: "",
		Writer:              writer,
		ManifestMIMEType:    manifestType,
		ForceCompress:       c.Bool("compress"),
	}

	// only one image is supported for now
	// future pull requests will fix this
	for _, image := range args {
		dest := dst
		// need dest to be in the format transport:path:reference for the following transports
		if strings.Contains(dst, libpod.OCIArchive) || strings.Contains(dst, libpod.DockerArchive) {
			dest = dst + ":" + image
		}
		if err := runtime.PushImage(image, dest, saveOpts); err != nil {
			if err2 := os.Remove(output); err2 != nil {
				logrus.Errorf("error deleting %q: %v", output, err)
			}
			return errors.Wrapf(err, "unable to save %q", image)
		}
	}
	return nil
}