summaryrefslogtreecommitdiff
path: root/cmd/podman/save.go
blob: 325140b76f17e1c175347718d124a99556bbc3c5 (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
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
package main

import (
	"fmt"
	"io"
	"os"
	"strings"

	"github.com/containers/image/directory"
	dockerarchive "github.com/containers/image/docker/archive"
	"github.com/containers/image/docker/reference"
	"github.com/containers/image/manifest"
	ociarchive "github.com/containers/image/oci/archive"
	"github.com/containers/image/types"
	"github.com/containers/libpod/cmd/podman/libpodruntime"
	libpodImage "github.com/containers/libpod/libpod/image"
	imgspecv1 "github.com/opencontainers/image-spec/specs-go/v1"
	"github.com/pkg/errors"
	"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:          sortFlags(saveFlags),
		Action:         saveCmd,
		ArgsUsage:      "",
		SkipArgReorder: true,
		OnUsageError:   usageErrorHandler,
	}
)

// 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 := libpodruntime.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.Stderr
	}

	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")
		}
	}
	if err := validateFileName(output); err != nil {
		return err
	}

	source := args[0]
	newImage, err := runtime.ImageRuntime().NewFromLocal(source)
	if err != nil {
		return err
	}

	var destRef types.ImageReference
	var manifestType string
	switch c.String("format") {
	case "oci-archive":
		destImageName := imageNameForSaveDestination(newImage, source)
		destRef, err = ociarchive.NewReference(output, destImageName) // destImageName may be ""
		if err != nil {
			return errors.Wrapf(err, "error getting OCI archive ImageReference for (%q, %q)", output, destImageName)
		}
	case "oci-dir":
		destRef, err = directory.NewReference(output)
		if err != nil {
			return errors.Wrapf(err, "error getting directory ImageReference for %q", output)
		}
		manifestType = imgspecv1.MediaTypeImageManifest
	case "docker-dir":
		destRef, err = directory.NewReference(output)
		if err != nil {
			return errors.Wrapf(err, "error getting directory ImageReference for %q", output)
		}
		manifestType = manifest.DockerV2Schema2MediaType
	case "docker-archive", "":
		dst := output
		destImageName := imageNameForSaveDestination(newImage, source)
		if destImageName != "" {
			dst = fmt.Sprintf("%s:%s", dst, destImageName)
		}
		destRef, err = dockerarchive.ParseReference(dst) // FIXME? Add dockerarchive.NewReference
		if err != nil {
			return errors.Wrapf(err, "error getting Docker archive ImageReference for %q", dst)
		}
	default:
		return errors.Errorf("unknown format option %q", c.String("format"))
	}

	// supports saving multiple tags to the same tar archive
	var additionaltags []reference.NamedTagged
	if len(args) > 1 {
		additionaltags, err = libpodImage.GetAdditionalTags(args[1:])
		if err != nil {
			return err
		}
	}
	if err := newImage.PushImageToReference(getContext(), destRef, manifestType, "", "", writer, c.Bool("compress"), libpodImage.SigningOptions{}, &libpodImage.DockerRegistryOptions{}, additionaltags); 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", args)
	}

	return nil
}

// imageNameForSaveDestination returns a Docker-like reference appropriate for saving img,
// which the user referred to as imgUserInput; or an empty string, if there is no appropriate
// reference.
func imageNameForSaveDestination(img *libpodImage.Image, imgUserInput string) string {
	if strings.Contains(img.ID(), imgUserInput) {
		return ""
	}

	prepend := ""
	localRegistryPrefix := fmt.Sprintf("%s/", libpodImage.DefaultLocalRegistry)
	if !strings.HasPrefix(imgUserInput, localRegistryPrefix) {
		// we need to check if localhost was added to the image name in NewFromLocal
		for _, name := range img.Names() {
			// If the user is saving an image in the localhost registry,  getLocalImage need
			// a name that matches the format localhost/<tag1>:<tag2> or localhost/<tag>:latest to correctly
			// set up the manifest and save.
			if strings.HasPrefix(name, localRegistryPrefix) && (strings.HasSuffix(name, imgUserInput) || strings.HasSuffix(name, fmt.Sprintf("%s:latest", imgUserInput))) {
				prepend = localRegistryPrefix
				break
			}
		}
	}
	return fmt.Sprintf("%s%s", prepend, imgUserInput)
}