// allowV1Fallback checks if the error is a possible reason to fallback to v1
// (even if confirmedV2 has been set already), and if so, wraps the error in
// a fallbackError with confirmedV2 set to false. Otherwise, it returns the
// error unmodified.
func allowV1Fallback(err error) error {
switch v := err.(type) {
case errcode.Errors:
if len(v) != 0 {
if v0, ok := v[0].(errcode.Error); ok && registry.ShouldV2Fallback(v0) {
return fallbackError{err: err, confirmedV2: false}
}
}
case errcode.Error:
if registry.ShouldV2Fallback(v) {
return fallbackError{err: err, confirmedV2: false}
}
}
return err
}
func (p *v2Puller) pullV2Tag(ctx context.Context, ref reference.Named) (tagUpdated bool, err error) {
tagOrDigest := ""
if tagged, isTagged := ref.(reference.NamedTagged); isTagged {
tagOrDigest = tagged.Tag()
} else if digested, isCanonical := ref.(reference.Canonical); isCanonical {
tagOrDigest = digested.Digest().String()
} else {
return false, fmt.Errorf("internal error: reference has neither a tag nor a digest: %s", ref.String())
}
logrus.Debugf("Pulling ref from V2 registry: %q", tagOrDigest)
manSvc, err := p.repo.Manifests(ctx)
if err != nil {
return false, err
}
unverifiedManifest, err := manSvc.GetByTag(tagOrDigest)
if err != nil {
// If this manifest did not exist, we should allow a possible
// fallback to the v1 protocol, because dual-version setups may
// not host all manifests with the v2 protocol. We may also get
// a "not authorized" error if the manifest doesn't exist.
switch v := err.(type) {
case errcode.Errors:
if len(v) != 0 {
if v0, ok := v[0].(errcode.Error); ok && registry.ShouldV2Fallback(v0) {
p.confirmedV2 = false
}
}
case errcode.Error:
if registry.ShouldV2Fallback(v) {
p.confirmedV2 = false
}
}
return false, err
}
if unverifiedManifest == nil {
return false, fmt.Errorf("image manifest does not exist for tag or digest %q", tagOrDigest)
}
// If GetByTag succeeded, we can be confident that the registry on
// the other side speaks the v2 protocol.
p.confirmedV2 = true
var verifiedManifest *schema1.Manifest
verifiedManifest, err = verifyManifest(unverifiedManifest, ref)
if err != nil {
return false, err
}
rootFS := image.NewRootFS()
if err := detectBaseLayer(p.config.ImageStore, verifiedManifest, rootFS); err != nil {
return false, err
}
// remove duplicate layers and check parent chain validity
err = fixManifestLayers(verifiedManifest)
if err != nil {
return false, err
}
progress.Message(p.config.ProgressOutput, tagOrDigest, "Pulling from "+p.repo.Name())
var descriptors []xfer.DownloadDescriptor
// Image history converted to the new format
var history []image.History
// Note that the order of this loop is in the direction of bottom-most
// to top-most, so that the downloads slice gets ordered correctly.
for i := len(verifiedManifest.FSLayers) - 1; i >= 0; i-- {
blobSum := verifiedManifest.FSLayers[i].BlobSum
var throwAway struct {
ThrowAway bool `json:"throwaway,omitempty"`
}
if err := json.Unmarshal([]byte(verifiedManifest.History[i].V1Compatibility), &throwAway); err != nil {
return false, err
}
h, err := v1.HistoryFromConfig([]byte(verifiedManifest.History[i].V1Compatibility), throwAway.ThrowAway)
if err != nil {
return false, err
}
history = append(history, h)
if throwAway.ThrowAway {
continue
}
layerDescriptor := &v2LayerDescriptor{
digest: blobSum,
repo: p.repo,
blobSumService: p.blobSumService,
}
descriptors = append(descriptors, layerDescriptor)
}
resultRootFS, release, err := p.config.DownloadManager.Download(ctx, *rootFS, descriptors, p.config.ProgressOutput)
if err != nil {
return false, err
}
defer release()
config, err := v1.MakeConfigFromV1Config([]byte(verifiedManifest.History[0].V1Compatibility), &resultRootFS, history)
if err != nil {
return false, err
}
imageID, err := p.config.ImageStore.Create(config)
if err != nil {
return false, err
}
manifestDigest, _, err := digestFromManifest(unverifiedManifest, p.repoInfo)
if err != nil {
return false, err
}
if manifestDigest != "" {
progress.Message(p.config.ProgressOutput, "", "Digest: "+manifestDigest.String())
}
oldTagImageID, err := p.config.ReferenceStore.Get(ref)
if err == nil && oldTagImageID == imageID {
return false, nil
}
if canonical, ok := ref.(reference.Canonical); ok {
if err = p.config.ReferenceStore.AddDigest(canonical, imageID, true); err != nil {
return false, err
}
} else if err = p.config.ReferenceStore.AddTag(ref, imageID, true); err != nil {
return false, err
}
return true, nil
}