summaryrefslogtreecommitdiff
path: root/libpod/image/image.go
blob: c9f03ebef67ff19dcfa0c2ad6192d49cfd910d56 (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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
package image

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"strings"
	"syscall"
	"time"

	types2 "github.com/containernetworking/cni/pkg/types"
	cp "github.com/containers/image/copy"
	"github.com/containers/image/docker/reference"
	is "github.com/containers/image/storage"
	"github.com/containers/image/tarball"
	"github.com/containers/image/transports/alltransports"
	"github.com/containers/image/types"
	"github.com/containers/storage"
	"github.com/containers/storage/pkg/reexec"
	"github.com/opencontainers/go-digest"
	ociv1 "github.com/opencontainers/image-spec/specs-go/v1"
	"github.com/pkg/errors"
	"github.com/projectatomic/libpod/libpod/common"
	"github.com/projectatomic/libpod/libpod/driver"
	"github.com/projectatomic/libpod/pkg/inspect"
	"github.com/projectatomic/libpod/pkg/util"
)

// imageConversions is used to cache image "cast" types
type imageConversions struct {
	imgRef   types.Image
	storeRef types.ImageReference
}

// Image is the primary struct for dealing with images
// It is still very much a work in progress
type Image struct {
	// Adding these two structs for now but will cull when we near
	// completion of this library.
	imageConversions
	inspect.ImageData
	inspect.ImageResult
	inspectInfo *types.ImageInspectInfo
	InputName   string
	Local       bool
	//runtime   *libpod.Runtime
	image        *storage.Image
	imageruntime *Runtime
	repotagsMap  map[string][]string
}

// Runtime contains the store
type Runtime struct {
	store               storage.Store
	SignaturePolicyPath string
}

// NewImageRuntimeFromStore creates an ImageRuntime based on a provided store
func NewImageRuntimeFromStore(store storage.Store) *Runtime {
	return &Runtime{
		store: store,
	}
}

// NewImageRuntimeFromOptions creates an Image Runtime including the store given
// store options
func NewImageRuntimeFromOptions(options storage.StoreOptions) (*Runtime, error) {
	if reexec.Init() {
		return nil, errors.Errorf("unable to reexec")
	}
	store, err := setStore(options)
	if err != nil {
		return nil, err
	}

	return &Runtime{
		store: store,
	}, nil
}

func setStore(options storage.StoreOptions) (storage.Store, error) {
	store, err := storage.GetStore(options)
	if err != nil {
		return nil, err
	}
	is.Transport.SetStore(store)
	return store, nil
}

// newFromStorage creates a new image object from a storage.Image
func (ir *Runtime) newFromStorage(img *storage.Image) *Image {
	image := Image{
		InputName:    img.ID,
		Local:        true,
		imageruntime: ir,
		image:        img,
	}
	return &image
}

// NewFromLocal creates a new image object that is intended
// to only deal with local images already in the store (or
// its aliases)
func (ir *Runtime) NewFromLocal(name string) (*Image, error) {
	image := Image{
		InputName:    name,
		Local:        true,
		imageruntime: ir,
	}
	localImage, err := image.getLocalImage()
	if err != nil {
		return nil, err
	}
	image.image = localImage
	return &image, nil
}

// New creates a new image object where the image could be local
// or remote
func (ir *Runtime) New(ctx context.Context, name, signaturePolicyPath, authfile string, writer io.Writer, dockeroptions *DockerRegistryOptions, signingoptions SigningOptions, forcePull, forceSecure bool) (*Image, error) {
	// We don't know if the image is local or not ... check local first
	newImage := Image{
		InputName:    name,
		Local:        false,
		imageruntime: ir,
	}
	if !forcePull {
		localImage, err := newImage.getLocalImage()
		if err == nil {
			newImage.Local = true
			newImage.image = localImage
			return &newImage, nil
		}
	}

	// The image is not local
	if signaturePolicyPath == "" {
		signaturePolicyPath = ir.SignaturePolicyPath
	}
	imageName, err := newImage.pullImage(ctx, writer, authfile, signaturePolicyPath, signingoptions, dockeroptions, forceSecure)
	if err != nil {
		return nil, errors.Wrapf(err, "unable to pull %s", name)
	}

	newImage.InputName = imageName
	img, err := newImage.getLocalImage()
	if err != nil {
		return nil, errors.Wrapf(err, "error retrieving local image after pulling %s", name)
	}
	newImage.image = img
	return &newImage, nil
}

// Shutdown closes down the storage and require a bool arg as to
// whether it should do so forcibly.
func (ir *Runtime) Shutdown(force bool) error {
	_, err := ir.store.Shutdown(force)
	return err
}

func (i *Image) reloadImage() error {
	newImage, err := i.imageruntime.getImage(i.ID())
	if err != nil {
		return errors.Wrapf(err, "unable to reload image")
	}
	i.image = newImage.image
	return nil
}

// stringSha256 strips sha256 from user input
func stripSha256(name string) string {
	if strings.HasPrefix(name, "sha256:") && len(name) > 7 {
		return name[7:]
	}
	return name
}

// getLocalImage resolves an unknown input describing an image and
// returns a storage.Image or an error. It is used by NewFromLocal.
func (i *Image) getLocalImage() (*storage.Image, error) {
	imageError := fmt.Sprintf("unable to find '%s' in local storage", i.InputName)
	if i.InputName == "" {
		return nil, errors.Errorf("input name is blank")
	}
	var taggedName string
	img, err := i.imageruntime.getImage(stripSha256(i.InputName))
	if err == nil {
		return img.image, err
	}

	// container-storage wasn't able to find it in its current form
	// check if the input name has a tag, and if not, run it through
	// again
	decomposedImage, err := decompose(i.InputName)
	if err != nil {
		return nil, err
	}
	// the inputname isn't tagged, so we assume latest and try again
	if !decomposedImage.isTagged {
		taggedName = fmt.Sprintf("%s:latest", i.InputName)
		img, err = i.imageruntime.getImage(taggedName)
		if err == nil {
			return img.image, nil
		}
	}
	hasReg, err := i.hasRegistry()
	if err != nil {
		return nil, errors.Wrapf(err, imageError)
	}

	// if the input name has a registry in it, the image isnt here
	if hasReg {
		return nil, errors.Errorf("%s", imageError)
	}

	// grab all the local images
	images, err := i.imageruntime.GetImages()
	if err != nil {
		return nil, err
	}

	// check the repotags of all images for a match
	repoImage, err := findImageInRepotags(decomposedImage, images)
	if err == nil {
		return repoImage, nil
	}
	return nil, errors.Wrapf(err, imageError)
}

// hasRegistry returns a bool/err response if the image has a registry in its
// name
func (i *Image) hasRegistry() (bool, error) {
	imgRef, err := reference.Parse(i.InputName)
	if err != nil {
		return false, err
	}
	registry := reference.Domain(imgRef.(reference.Named))
	if registry != "" {
		return true, nil
	}
	return false, nil
}

// ID returns the image ID as a string
func (i *Image) ID() string {
	return i.image.ID
}

// Digest returns the image's digest
func (i *Image) Digest() digest.Digest {
	return i.image.Digest
}

// Manifest returns the image's manifest as a byte array
// and manifest type as a string.  The manifest type is
// MediaTypeImageManifest from ociv1.
func (i *Image) Manifest(ctx context.Context) ([]byte, string, error) {
	imgRef, err := i.toImageRef(ctx)
	if err != nil {
		return nil, "", err
	}
	return imgRef.Manifest(ctx)
}

// Names returns a string array of names associated with the image
func (i *Image) Names() []string {
	return i.image.Names
}

// Created returns the time the image was created
func (i *Image) Created() time.Time {
	return i.image.Created
}

// TopLayer returns the top layer id as a string
func (i *Image) TopLayer() string {
	return i.image.TopLayer
}

// Remove an image; container removal for the image must be done
// outside the context of images
func (i *Image) Remove(force bool) error {
	_, err := i.imageruntime.store.DeleteImage(i.ID(), true)
	return err
}

// Decompose an Image
func (i *Image) Decompose() error {
	return types2.NotImplementedError
}

// TODO: Rework this method to not require an assembly of the fq name with transport
/*
// GetManifest tries to GET an images manifest, returns nil on success and err on failure
func (i *Image) GetManifest() error {
	pullRef, err := alltransports.ParseImageName(i.assembleFqNameTransport())
	if err != nil {
		return errors.Errorf("unable to parse '%s'", i.Names()[0])
	}
	imageSource, err := pullRef.NewImageSource(nil)
	if err != nil {
		return errors.Wrapf(err, "unable to create new image source")
	}
	_, _, err = imageSource.GetManifest(nil)
	if err == nil {
		return nil
	}
	return err
}
*/

// getImage retrieves an image matching the given name or hash from system
// storage
// If no matching image can be found, an error is returned
func (ir *Runtime) getImage(image string) (*Image, error) {
	var img *storage.Image
	ref, err := is.Transport.ParseStoreReference(ir.store, image)
	if err == nil {
		img, err = is.Transport.GetStoreImage(ir.store, ref)
	}
	if err != nil {
		img2, err2 := ir.store.Image(image)
		if err2 != nil {
			if ref == nil {
				return nil, errors.Wrapf(err, "error parsing reference to image %q", image)
			}
			return nil, errors.Wrapf(err, "unable to locate image %q", image)
		}
		img = img2
	}
	newImage := ir.newFromStorage(img)
	return newImage, nil
}

// GetImages retrieves all images present in storage
func (ir *Runtime) GetImages() ([]*Image, error) {
	var newImages []*Image
	images, err := ir.store.Images()
	if err != nil {
		return nil, err
	}
	for _, i := range images {
		// iterating over these, be careful to not iterate on the literal
		// pointer.
		image := i
		img := ir.newFromStorage(&image)
		newImages = append(newImages, img)
	}
	return newImages, nil
}

// 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
}

// TagImage adds a tag to the given image
func (i *Image) TagImage(tag string) error {
	i.reloadImage()
	decomposedTag, err := decompose(tag)
	if err != nil {
		return err
	}
	// If the input does not have a tag, we need to add one (latest)
	if !decomposedTag.isTagged {
		tag = fmt.Sprintf("%s:%s", tag, decomposedTag.tag)
	}
	tags := i.Names()
	if util.StringInSlice(tag, tags) {
		return nil
	}
	tags = append(tags, tag)
	if err := i.imageruntime.store.SetNames(i.ID(), tags); err != nil {
		return err
	}
	i.reloadImage()
	return nil
}

// UntagImage removes a tag from the given image
func (i *Image) UntagImage(tag string) error {
	i.reloadImage()
	var newTags []string
	tags := i.Names()
	if !util.StringInSlice(tag, tags) {
		return nil
	}
	for _, t := range tags {
		if tag != t {
			newTags = append(newTags, t)
		}
	}
	if err := i.imageruntime.store.SetNames(i.ID(), newTags); err != nil {
		return err
	}
	i.reloadImage()
	return nil
}

// PushImage pushes the given image to a location described by the given path
func (i *Image) PushImage(ctx context.Context, destination, manifestMIMEType, authFile, signaturePolicyPath string, writer io.Writer, forceCompress bool, signingOptions SigningOptions, dockerRegistryOptions *DockerRegistryOptions) error {
	if destination == "" {
		return errors.Wrapf(syscall.EINVAL, "destination image name must be specified")
	}

	// Get the destination Image Reference
	dest, err := alltransports.ParseImageName(destination)
	if err != nil {
		if hasTransport(destination) {
			return errors.Wrapf(err, "error getting destination imageReference for %q", destination)
		}
		// Try adding the images default transport
		destination2 := DefaultTransport + destination
		dest, err = alltransports.ParseImageName(destination2)
		if err != nil {
			return err
		}
	}

	sc := GetSystemContext(signaturePolicyPath, authFile, forceCompress)

	policyContext, err := getPolicyContext(sc)
	if err != nil {
		return err
	}
	defer policyContext.Destroy()

	// Look up the source image, expecting it to be in local storage
	src, err := is.Transport.ParseStoreReference(i.imageruntime.store, i.ID())
	if err != nil {
		return errors.Wrapf(err, "error getting source imageReference for %q", i.InputName)
	}

	copyOptions := getCopyOptions(writer, signaturePolicyPath, nil, dockerRegistryOptions, signingOptions, authFile, manifestMIMEType, forceCompress)

	// Copy the image to the remote destination
	err = cp.Image(ctx, policyContext, dest, src, copyOptions)
	if err != nil {
		return errors.Wrapf(err, "Error copying image to the remote destination")
	}
	return nil
}

// MatchesID returns a bool based on if the input id
// matches the image's id
func (i *Image) MatchesID(id string) bool {
	return strings.HasPrefix(i.ID(), id)
}

// toStorageReference returns a *storageReference from an Image
func (i *Image) toStorageReference() (types.ImageReference, error) {
	var lookupName string
	if i.storeRef == nil {
		if i.image != nil {
			lookupName = i.ID()
		} else {
			lookupName = i.InputName
		}
		storeRef, err := is.Transport.ParseStoreReference(i.imageruntime.store, lookupName)
		if err != nil {
			return nil, err
		}
		i.storeRef = storeRef
	}
	return i.storeRef, nil
}

// ToImageRef returns an image reference type from an image
// TODO: Hopefully we can remove this exported function for mheon
func (i *Image) ToImageRef(ctx context.Context) (types.Image, error) {
	return i.toImageRef(ctx)
}

// toImageRef returns an Image Reference type from an image
func (i *Image) toImageRef(ctx context.Context) (types.Image, error) {
	if i == nil {
		return nil, errors.Errorf("cannot convert nil image to image reference")
	}
	if i.imgRef == nil {
		ref, err := is.Transport.ParseStoreReference(i.imageruntime.store, "@"+i.ID())
		if err != nil {
			return nil, errors.Wrapf(err, "error parsing reference to image %q", i.ID())
		}
		imgRef, err := ref.NewImage(ctx, nil)
		if err != nil {
			return nil, errors.Wrapf(err, "error reading image %q", i.ID())
		}
		i.imgRef = imgRef
	}
	return i.imgRef, nil
}

// sizer knows its size.
type sizer interface {
	Size() (int64, error)
}

//Size returns the size of the image
func (i *Image) Size(ctx context.Context) (*uint64, error) {
	storeRef, err := is.Transport.ParseStoreReference(i.imageruntime.store, i.ID())
	if err != nil {
		return nil, err
	}
	systemContext := &types.SystemContext{}
	img, err := storeRef.NewImageSource(ctx, systemContext)
	if err != nil {
		return nil, err
	}
	if s, ok := img.(sizer); ok {
		if sum, err := s.Size(); err == nil {
			usum := uint64(sum)
			return &usum, nil
		}
	}
	return nil, errors.Errorf("unable to determine size")
}

// DriverData gets the driver data from the store on a layer
func (i *Image) DriverData() (*inspect.Data, error) {
	topLayer, err := i.Layer()
	if err != nil {
		return nil, err
	}
	return driver.GetDriverData(i.imageruntime.store, topLayer.ID)
}

// Layer returns the image's top layer
func (i *Image) Layer() (*storage.Layer, error) {
	return i.imageruntime.store.Layer(i.image.TopLayer)
}

// History gets the history of an image and information about its layers
func (i *Image) History(ctx context.Context) ([]ociv1.History, []types.BlobInfo, error) {
	img, err := i.toImageRef(ctx)
	if err != nil {
		return nil, nil, err
	}
	oci, err := img.OCIConfig(ctx)
	if err != nil {
		return nil, nil, err
	}
	return oci.History, img.LayerInfos(), nil
}

// Dangling returns a bool if the image is "dangling"
func (i *Image) Dangling() bool {
	return len(i.Names()) == 0
}

// Labels returns the image's labels
func (i *Image) Labels(ctx context.Context) (map[string]string, error) {
	imgInspect, err := i.imageInspectInfo(ctx)
	if err != nil {
		return nil, nil
	}
	return imgInspect.Labels, nil
}

// Annotations returns the annotations of an image
func (i *Image) Annotations(ctx context.Context) (map[string]string, error) {
	manifest, manifestType, err := i.Manifest(ctx)
	if err != nil {
		return nil, err
	}
	annotations := make(map[string]string)
	switch manifestType {
	case ociv1.MediaTypeImageManifest:
		var m ociv1.Manifest
		if err := json.Unmarshal(manifest, &m); err == nil {
			for k, v := range m.Annotations {
				annotations[k] = v
			}
		}
	}
	return annotations, nil
}

// ociv1Image converts and image to an imgref and then an
// ociv1 image type
func (i *Image) ociv1Image(ctx context.Context) (*ociv1.Image, error) {
	imgRef, err := i.toImageRef(ctx)
	if err != nil {
		return nil, err
	}
	return imgRef.OCIConfig(ctx)
}

func (i *Image) imageInspectInfo(ctx context.Context) (*types.ImageInspectInfo, error) {
	if i.inspectInfo == nil {
		sr, err := i.toStorageReference()
		if err != nil {
			return nil, err
		}
		ic, err := sr.NewImage(ctx, &types.SystemContext{})
		if err != nil {
			return nil, err
		}
		imgInspect, err := ic.Inspect(ctx)
		if err != nil {
			return nil, err
		}
		i.inspectInfo = imgInspect
	}
	return i.inspectInfo, nil
}

// Inspect returns an image's inspect data
func (i *Image) Inspect(ctx context.Context) (*inspect.ImageData, error) {
	ociv1Img, err := i.ociv1Image(ctx)
	if err != nil {
		return nil, err
	}
	info, err := i.imageInspectInfo(ctx)
	if err != nil {
		return nil, err
	}
	annotations, err := i.Annotations(ctx)
	if err != nil {
		return nil, err
	}

	size, err := i.Size(ctx)
	if err != nil {
		return nil, err
	}

	var repoDigests []string
	for _, name := range i.Names() {
		repoDigests = append(repoDigests, strings.SplitN(name, ":", 2)[0]+"@"+i.Digest().String())
	}

	driver, err := i.DriverData()
	if err != nil {
		return nil, err
	}

	data := &inspect.ImageData{
		ID:              i.ID(),
		RepoTags:        i.Names(),
		RepoDigests:     repoDigests,
		Comment:         ociv1Img.History[0].Comment,
		Created:         ociv1Img.Created,
		Author:          ociv1Img.Author,
		Architecture:    ociv1Img.Architecture,
		Os:              ociv1Img.OS,
		ContainerConfig: &ociv1Img.Config,
		Version:         info.DockerVersion,
		Size:            int64(*size),
		VirtualSize:     int64(*size),
		Annotations:     annotations,
		Digest:          i.Digest(),
		Labels:          info.Labels,
		RootFS: &inspect.RootFS{
			Type:   ociv1Img.RootFS.Type,
			Layers: ociv1Img.RootFS.DiffIDs,
		},
		GraphDriver: driver,
	}
	return data, nil
}

// Import imports and image into the store and returns an image
func (ir *Runtime) Import(ctx context.Context, path, reference string, writer io.Writer, signingOptions SigningOptions, imageConfig ociv1.Image) (*Image, error) {
	file := TarballTransport + ":" + path
	src, err := alltransports.ParseImageName(file)
	if err != nil {
		return nil, errors.Wrapf(err, "error parsing image name %q", path)
	}

	updater, ok := src.(tarball.ConfigUpdater)
	if !ok {
		return nil, errors.Wrapf(err, "unexpected type, a tarball reference should implement tarball.ConfigUpdater")
	}

	annotations := make(map[string]string)

	//	config imgspecv1.Image
	err = updater.ConfigUpdate(imageConfig, annotations)
	if err != nil {
		return nil, errors.Wrapf(err, "error updating image config")
	}

	sc := common.GetSystemContext("", "", false)

	// if reference not given, get the image digest
	if reference == "" {
		reference, err = getImageDigest(ctx, src, sc)
		if err != nil {
			return nil, err
		}
	}
	policyContext, err := getPolicyContext(sc)
	if err != nil {
		return nil, err
	}
	defer policyContext.Destroy()
	copyOptions := getCopyOptions(writer, "", nil, nil, signingOptions, "", "", false)
	dest, err := is.Transport.ParseStoreReference(ir.store, reference)
	if err != nil {
		errors.Wrapf(err, "error getting image reference for %q", reference)
	}
	if err = cp.Image(ctx, policyContext, dest, src, copyOptions); err != nil {
		return nil, err
	}
	return ir.NewFromLocal(reference)
}

// MatchRepoTag takes a string and tries to match it against an
// image's repotags
func (i *Image) MatchRepoTag(input string) (string, error) {
	results := make(map[int][]string)
	var maxCount int
	// first check if we have an exact match with the input
	if util.StringInSlice(input, i.Names()) {
		return input, nil
	}
	// next check if we are missing the tag
	dcImage, err := decompose(input)
	if err != nil {
		return "", err
	}
	for _, repoName := range i.Names() {
		count := 0
		dcRepoName, err := decompose(repoName)
		if err != nil {
			return "", err
		}
		if dcRepoName.registry == dcImage.registry && dcImage.registry != "" {
			count++
		}
		if dcRepoName.name == dcImage.name && dcImage.name != "" {
			count++
		} else if splitString(dcRepoName.name) == splitString(dcImage.name) {
			count++
		}
		if dcRepoName.tag == dcImage.tag {
			count++
		}
		results[count] = append(results[count], repoName)
		if count > maxCount {
			maxCount = count
		}
	}
	if maxCount == 0 {
		return "", errors.Errorf("unable to match user input to any specific repotag")
	}
	if len(results[maxCount]) > 1 {
		return "", errors.Errorf("user input matched multiple repotags for the image")
	}
	return results[maxCount][0], nil
}

// splitString splits input string by / and returns the last array item
func splitString(input string) string {
	split := strings.Split(input, "/")
	return split[len(split)-1]
}

// InputIsID returns a bool if the user input for an image
// is the image's partial or full id
func (i *Image) InputIsID() bool {
	return strings.HasPrefix(i.ID(), i.InputName)
}