aboutsummaryrefslogtreecommitdiff
path: root/vendor/github.com/projectatomic/buildah/pull.go
blob: edfaa62166cd3c222690692e0d0776b651f11ab9 (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
183
184
185
186
187
188
189
190
191
package buildah

import (
	"context"
	"strings"

	cp "github.com/containers/image/copy"
	"github.com/containers/image/docker/reference"
	tarfile "github.com/containers/image/docker/tarfile"
	ociarchive "github.com/containers/image/oci/archive"
	"github.com/containers/image/signature"
	is "github.com/containers/image/storage"
	"github.com/containers/image/transports"
	"github.com/containers/image/transports/alltransports"
	"github.com/containers/image/types"
	"github.com/containers/storage"
	"github.com/pkg/errors"
	"github.com/projectatomic/buildah/util"
	"github.com/sirupsen/logrus"
)

func localImageNameForReference(ctx context.Context, store storage.Store, srcRef types.ImageReference, spec string) (string, error) {
	if srcRef == nil {
		return "", errors.Errorf("reference to image is empty")
	}
	split := strings.SplitN(spec, ":", 2)
	file := split[len(split)-1]
	var name string
	switch srcRef.Transport().Name() {
	case util.DockerArchive:
		tarSource, err := tarfile.NewSourceFromFile(file)
		if err != nil {
			return "", err
		}
		manifest, err := tarSource.LoadTarManifest()
		if err != nil {
			return "", errors.Errorf("error retrieving manifest.json: %v", err)
		}
		// to pull the first image stored in the tar file
		if len(manifest) == 0 {
			// use the hex of the digest if no manifest is found
			name, err = getImageDigest(ctx, srcRef, nil)
			if err != nil {
				return "", err
			}
		} else {
			if len(manifest[0].RepoTags) > 0 {
				name = manifest[0].RepoTags[0]
			} else {
				// If the input image has no repotags, we need to feed it a dest anyways
				name, err = getImageDigest(ctx, srcRef, nil)
				if err != nil {
					return "", err
				}
			}
		}
	case util.OCIArchive:
		// retrieve the manifest from index.json to access the image name
		manifest, err := ociarchive.LoadManifestDescriptor(srcRef)
		if err != nil {
			return "", errors.Wrapf(err, "error loading manifest for %q", srcRef)
		}
		// if index.json has no reference name, compute the image digest instead
		if manifest.Annotations == nil || manifest.Annotations["org.opencontainers.image.ref.name"] == "" {
			name, err = getImageDigest(ctx, srcRef, nil)
			if err != nil {
				return "", err
			}
		} else {
			name = manifest.Annotations["org.opencontainers.image.ref.name"]
		}
	case util.DirTransport:
		// supports pull from a directory
		name = split[1]
		// remove leading "/"
		if name[:1] == "/" {
			name = name[1:]
		}
	default:
		ref := srcRef.DockerReference()
		if ref == nil {
			name = srcRef.StringWithinTransport()
			_, err := is.Transport.ParseStoreReference(store, name)
			if err == nil {
				return name, nil
			}
			if strings.LastIndex(name, "/") != -1 {
				name = name[strings.LastIndex(name, "/")+1:]
				_, err = is.Transport.ParseStoreReference(store, name)
				if err == nil {
					return name, nil
				}
			}
			return "", errors.Errorf("reference to image %q is not a named reference", transports.ImageName(srcRef))
		}

		if named, ok := ref.(reference.Named); ok {
			name = named.Name()
			if namedTagged, ok := ref.(reference.NamedTagged); ok {
				name = name + ":" + namedTagged.Tag()
			}
			if canonical, ok := ref.(reference.Canonical); ok {
				name = name + "@" + canonical.Digest().String()
			}
		}
	}

	if _, err := is.Transport.ParseStoreReference(store, name); err != nil {
		return "", errors.Wrapf(err, "error parsing computed local image name %q", name)
	}
	return name, nil
}

func pullImage(ctx context.Context, store storage.Store, imageName string, options BuilderOptions, sc *types.SystemContext) (types.ImageReference, error) {
	spec := imageName
	srcRef, err := alltransports.ParseImageName(spec)
	if err != nil {
		if options.Transport == "" {
			return nil, errors.Wrapf(err, "error parsing image name %q", spec)
		}
		transport := options.Transport
		if transport != DefaultTransport {
			transport = transport + ":"
		}
		spec = transport + spec
		srcRef2, err2 := alltransports.ParseImageName(spec)
		if err2 != nil {
			return nil, errors.Wrapf(err2, "error parsing image name %q", spec)
		}
		srcRef = srcRef2
	}

	destName, err := localImageNameForReference(ctx, store, srcRef, spec)
	if err != nil {
		return nil, errors.Wrapf(err, "error computing local image name for %q", transports.ImageName(srcRef))
	}
	if destName == "" {
		return nil, errors.Errorf("error computing local image name for %q", transports.ImageName(srcRef))
	}

	destRef, err := is.Transport.ParseStoreReference(store, destName)
	if err != nil {
		return nil, errors.Wrapf(err, "error parsing image name %q", destName)
	}

	img, err := srcRef.NewImageSource(ctx, sc)
	if err != nil {
		return nil, errors.Wrapf(err, "error initializing %q as an image source", spec)
	}
	img.Close()

	policy, err := signature.DefaultPolicy(sc)
	if err != nil {
		return nil, errors.Wrapf(err, "error obtaining default signature policy")
	}

	policyContext, err := signature.NewPolicyContext(policy)
	if err != nil {
		return nil, errors.Wrapf(err, "error creating new signature policy context")
	}

	defer func() {
		if err2 := policyContext.Destroy(); err2 != nil {
			logrus.Debugf("error destroying signature policy context: %v", err2)
		}
	}()

	logrus.Debugf("copying %q to %q", spec, destName)

	err = cp.Image(ctx, policyContext, destRef, srcRef, getCopyOptions(options.ReportWriter, options.SystemContext, nil, ""))
	if err == nil {
		return destRef, nil
	}
	return nil, err
}

// getImageDigest creates an image object and uses the hex value of the digest as the image ID
// for parsing the store reference
func getImageDigest(ctx context.Context, src types.ImageReference, sc *types.SystemContext) (string, error) {
	newImg, err := src.NewImage(ctx, sc)
	if err != nil {
		return "", err
	}
	defer newImg.Close()

	digest := newImg.ConfigInfo().Digest
	if err = digest.Validate(); err != nil {
		return "", errors.Wrapf(err, "error getting config info")
	}
	return "@" + digest.Hex(), nil
}