func (p *v1Pusher) pushImage(ctx context.Context, v1Image v1Image, ep string) (checksum string, err error) {
l := v1Image.Layer()
v1ID := v1Image.V1ID()
truncID := stringid.TruncateID(l.DiffID().String())
jsonRaw := v1Image.Config()
progress.Update(p.config.ProgressOutput, truncID, "Pushing")
// General rule is to use ID for graph accesses and compatibilityID for
// calls to session.registry()
imgData := ®istry.ImgData{
ID: v1ID,
}
// Send the json
if err := p.session.PushImageJSONRegistry(imgData, jsonRaw, ep); err != nil {
if err == registry.ErrAlreadyExists {
progress.Update(p.config.ProgressOutput, truncID, "Image already pushed, skipping")
return "", nil
}
return "", err
}
arch, err := l.TarStream()
if err != nil {
return "", err
}
defer arch.Close()
// don't care if this fails; best effort
size, _ := l.DiffSize()
// Send the layer
logrus.Debugf("rendered layer for %s of [%d] size", v1ID, size)
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, arch), p.config.ProgressOutput, size, truncID, "Pushing")
defer reader.Close()
checksum, checksumPayload, err := p.session.PushImageLayerRegistry(v1ID, reader, ep, jsonRaw)
if err != nil {
return "", err
}
imgData.Checksum = checksum
imgData.ChecksumPayload = checksumPayload
// Send the checksum
if err := p.session.PushImageChecksumRegistry(imgData, ep); err != nil {
return "", err
}
if err := p.v1IDService.Set(v1ID, p.repoInfo.Index.Name, l.DiffID()); err != nil {
logrus.Warnf("Could not set v1 ID mapping: %v", err)
}
progress.Update(p.config.ProgressOutput, truncID, "Image successfully pushed")
return imgData.Checksum, nil
}
func (p *v1Puller) downloadImage(ctx context.Context, repoData *registry.RepositoryData, img *registry.ImgData, layersDownloaded *bool) error {
if img.Tag == "" {
logrus.Debugf("Image (id: %s) present in this repository but untagged, skipping", img.ID)
return nil
}
localNameRef, err := reference.WithTag(p.repoInfo.LocalName, img.Tag)
if err != nil {
retErr := fmt.Errorf("Image (id: %s) has invalid tag: %s", img.ID, img.Tag)
logrus.Debug(retErr.Error())
return retErr
}
if err := v1.ValidateID(img.ID); err != nil {
return err
}
progress.Updatef(p.config.ProgressOutput, stringid.TruncateID(img.ID), "Pulling image (%s) from %s", img.Tag, p.repoInfo.CanonicalName.Name())
success := false
var lastErr error
for _, ep := range p.repoInfo.Index.Mirrors {
ep += "v1/"
progress.Updatef(p.config.ProgressOutput, stringid.TruncateID(img.ID), fmt.Sprintf("Pulling image (%s) from %s, mirror: %s", img.Tag, p.repoInfo.CanonicalName.Name(), ep))
if err = p.pullImage(ctx, img.ID, ep, localNameRef, layersDownloaded); err != nil {
// Don't report errors when pulling from mirrors.
logrus.Debugf("Error pulling image (%s) from %s, mirror: %s, %s", img.Tag, p.repoInfo.CanonicalName.Name(), ep, err)
continue
}
success = true
break
}
if !success {
for _, ep := range repoData.Endpoints {
progress.Updatef(p.config.ProgressOutput, stringid.TruncateID(img.ID), "Pulling image (%s) from %s, endpoint: %s", img.Tag, p.repoInfo.CanonicalName.Name(), ep)
if err = p.pullImage(ctx, img.ID, ep, localNameRef, layersDownloaded); err != nil {
// It's not ideal that only the last error is returned, it would be better to concatenate the errors.
// As the error is also given to the output stream the user will see the error.
lastErr = err
progress.Updatef(p.config.ProgressOutput, stringid.TruncateID(img.ID), "Error pulling image (%s) from %s, endpoint: %s, %s", img.Tag, p.repoInfo.CanonicalName.Name(), ep, err)
continue
}
success = true
break
}
}
if !success {
err := fmt.Errorf("Error pulling image (%s) from %s, %v", img.Tag, p.repoInfo.CanonicalName.Name(), lastErr)
progress.Update(p.config.ProgressOutput, stringid.TruncateID(img.ID), err.Error())
return err
}
progress.Update(p.config.ProgressOutput, stringid.TruncateID(img.ID), "Download complete")
return nil
}
// lookupImageOnEndpoint checks the specified endpoint to see if an image exists
// and if it is absent then it sends the image id to the channel to be pushed.
func (p *v1Pusher) lookupImageOnEndpoint(wg *sync.WaitGroup, endpoint string, images chan v1Image, imagesToPush chan string) {
defer wg.Done()
for image := range images {
v1ID := image.V1ID()
truncID := stringid.TruncateID(image.Layer().DiffID().String())
if err := p.session.LookupRemoteImage(v1ID, endpoint); err != nil {
logrus.Errorf("Error in LookupRemoteImage: %s", err)
imagesToPush <- v1ID
progress.Update(p.config.ProgressOutput, truncID, "Waiting")
} else {
progress.Update(p.config.ProgressOutput, truncID, "Already exists")
}
}
}
func (ld *v1LayerDescriptor) Download(ctx context.Context, progressOutput progress.Output) (io.ReadCloser, int64, error) {
progress.Update(progressOutput, ld.ID(), "Pulling fs layer")
layerReader, err := ld.session.GetRemoteImageLayer(ld.v1LayerID, ld.endpoint, ld.layerSize)
if err != nil {
progress.Update(progressOutput, ld.ID(), "Error pulling dependent layers")
if uerr, ok := err.(*url.Error); ok {
err = uerr.Err
}
if terr, ok := err.(net.Error); ok && terr.Timeout() {
return nil, 0, err
}
return nil, 0, xfer.DoNotRetry{Err: err}
}
*ld.layersDownloaded = true
ld.tmpFile, err = ioutil.TempFile("", "GetImageBlob")
if err != nil {
layerReader.Close()
return nil, 0, err
}
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, layerReader), progressOutput, ld.layerSize, ld.ID(), "Downloading")
defer reader.Close()
_, err = io.Copy(ld.tmpFile, reader)
if err != nil {
ld.Close()
return nil, 0, err
}
progress.Update(progressOutput, ld.ID(), "Download complete")
logrus.Debugf("Downloaded %s to tempfile %s", ld.ID(), ld.tmpFile.Name())
ld.tmpFile.Seek(0, 0)
// hand off the temporary file to the download manager, so it will only
// be closed once
tmpFile := ld.tmpFile
ld.tmpFile = nil
return ioutils.NewReadCloserWrapper(tmpFile, func() error {
tmpFile.Close()
err := os.RemoveAll(tmpFile.Name())
if err != nil {
logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
}
return err
}), ld.layerSize, nil
}
// Upload is a blocking function which ensures the listed layers are present on
// the remote registry. It uses the string returned by the Key method to
// deduplicate uploads.
func (lum *LayerUploadManager) Upload(ctx context.Context, layers []UploadDescriptor, progressOutput progress.Output) error {
var (
uploads []*uploadTransfer
dedupDescriptors = make(map[string]struct{})
)
for _, descriptor := range layers {
progress.Update(progressOutput, descriptor.ID(), "Preparing")
key := descriptor.Key()
if _, present := dedupDescriptors[key]; present {
continue
}
dedupDescriptors[key] = struct{}{}
xferFunc := lum.makeUploadFunc(descriptor)
upload, watcher := lum.tm.Transfer(descriptor.Key(), xferFunc, progressOutput)
defer upload.Release(watcher)
uploads = append(uploads, upload.(*uploadTransfer))
}
for _, upload := range uploads {
select {
case <-ctx.Done():
return ctx.Err()
case <-upload.Transfer.Done():
if upload.err != nil {
return upload.err
}
}
}
return nil
}
func (pd *v2PushDescriptor) uploadUsingSession(
ctx context.Context,
progressOutput progress.Output,
diffID layer.DiffID,
layerUpload distribution.BlobWriter,
) (distribution.Descriptor, error) {
arch, err := pd.layer.TarStream()
if err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
// don't care if this fails; best effort
size, _ := pd.layer.DiffSize()
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, arch), progressOutput, size, pd.ID(), "Pushing")
compressedReader, compressionDone := compress(reader)
defer func() {
reader.Close()
<-compressionDone
}()
digester := digest.Canonical.New()
tee := io.TeeReader(compressedReader, digester.Hash())
nn, err := layerUpload.ReadFrom(tee)
compressedReader.Close()
if err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
pushDigest := digester.Digest()
if _, err := layerUpload.Commit(ctx, distribution.Descriptor{Digest: pushDigest}); err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
logrus.Debugf("uploaded layer %s (%s), %d bytes", diffID, pushDigest, nn)
progress.Update(progressOutput, pd.ID(), "Pushed")
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.TagAndAdd(diffID, pd.hmacKey, metadata.V2Metadata{
Digest: pushDigest,
SourceRepository: pd.repoInfo.FullName(),
}); err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
desc := distribution.Descriptor{
Digest: pushDigest,
MediaType: schema2.MediaTypeLayer,
Size: nn,
}
pd.pushState.Lock()
// If Commit succeeded, that's an indication that the remote registry speaks the v2 protocol.
pd.pushState.confirmedV2 = true
pd.pushState.remoteLayers[diffID] = desc
pd.pushState.Unlock()
return desc, nil
}
func (p *v1Puller) downloadLayerConfig(v1LayerID, endpoint string) (imgJSON []byte, imgSize int64, err error) {
progress.Update(p.config.ProgressOutput, stringid.TruncateID(v1LayerID), "Pulling metadata")
retries := 5
for j := 1; j <= retries; j++ {
imgJSON, imgSize, err := p.session.GetRemoteImageJSON(v1LayerID, endpoint)
if err != nil && j == retries {
progress.Update(p.config.ProgressOutput, stringid.TruncateID(v1LayerID), "Error pulling layer metadata")
return nil, 0, err
} else if err != nil {
time.Sleep(time.Duration(j) * 500 * time.Millisecond)
continue
}
return imgJSON, imgSize, nil
}
// not reached
return nil, 0, nil
}
func (ld *v1LayerDescriptor) Download(ctx context.Context, progressOutput progress.Output) (io.ReadCloser, int64, error) {
progress.Update(progressOutput, ld.ID(), "Pulling fs layer")
layerReader, err := ld.session.GetRemoteImageLayer(ld.v1LayerID, ld.endpoint, ld.layerSize)
if err != nil {
progress.Update(progressOutput, ld.ID(), "Error pulling dependent layers")
if uerr, ok := err.(*url.Error); ok {
err = uerr.Err
}
if terr, ok := err.(net.Error); ok && terr.Timeout() {
return nil, 0, err
}
return nil, 0, xfer.DoNotRetry{Err: err}
}
*ld.layersDownloaded = true
ld.tmpFile, err = ioutil.TempFile("", "GetImageBlob")
if err != nil {
layerReader.Close()
return nil, 0, err
}
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, layerReader), progressOutput, ld.layerSize, ld.ID(), "Downloading")
defer reader.Close()
_, err = io.Copy(ld.tmpFile, reader)
if err != nil {
ld.Close()
return nil, 0, err
}
progress.Update(progressOutput, ld.ID(), "Download complete")
logrus.Debugf("Downloaded %s to tempfile %s", ld.ID(), ld.tmpFile.Name())
ld.tmpFile.Seek(0, 0)
return ld.tmpFile, ld.layerSize, nil
}
// WriteImageBlobs writes the image blob to the storage layer
func WriteImageBlobs(images []*ImageWithMeta) error {
if options.standalone {
return nil
}
// iterate from parent to children
// so that portlayer can extract each layer
// on top of previous one
destination := DestinationDirectory()
for i := len(images) - 1; i >= 0; i-- {
image := images[i]
id := image.Image.ID
f, err := os.Open(path.Join(destination, id, id+".tar"))
if err != nil {
return fmt.Errorf("Failed to open file: %s", err)
}
defer f.Close()
fi, err := f.Stat()
if err != nil {
return fmt.Errorf("Failed to stat file: %s", err)
}
in := progress.NewProgressReader(
ioutils.NewCancelReadCloser(context.Background(), f),
po,
fi.Size(),
image.String(),
"Extracting",
)
defer in.Close()
// Write the image
err = WriteImage(image, in)
if err != nil {
return fmt.Errorf("Failed to write to image store: %s", err)
}
progress.Update(po, image.String(), "Pull complete")
}
if err := os.RemoveAll(destination); err != nil {
return fmt.Errorf("Failed to remove download directory: %s", err)
}
return nil
}
// WriteImageBlob writes the image blob to the storage layer
func (ic *ImageC) WriteImageBlob(image *ImageWithMeta, progressOutput progress.Output, cleanup bool) error {
defer trace.End(trace.Begin(image.Image.ID))
destination := DestinationDirectory(ic.Options)
id := image.Image.ID
log.Infof("Path: %s", path.Join(destination, id, id+".targ"))
f, err := os.Open(path.Join(destination, id, id+".tar"))
if err != nil {
return fmt.Errorf("Failed to open file: %s", err)
}
defer f.Close()
fi, err := f.Stat()
if err != nil {
return fmt.Errorf("Failed to stat file: %s", err)
}
in := progress.NewProgressReader(
ioutils.NewCancelReadCloser(context.Background(), f),
progressOutput,
fi.Size(),
image.String(),
"Extracting",
)
defer in.Close()
// Write the image
err = WriteImage(ic.Host, image, in)
if err != nil {
return fmt.Errorf("Failed to write to image store: %s", err)
}
progress.Update(progressOutput, image.String(), "Pull complete")
if cleanup {
if err := os.RemoveAll(destination); err != nil {
return fmt.Errorf("Failed to remove download directory: %s", err)
}
}
return nil
}
func (pd *v2PushDescriptor) Upload(ctx context.Context, progressOutput progress.Output) (distribution.Descriptor, error) {
if fs, ok := pd.layer.(distribution.Describable); ok {
if d := fs.Descriptor(); len(d.URLs) > 0 {
progress.Update(progressOutput, pd.ID(), "Skipped foreign layer")
return d, nil
}
}
diffID := pd.DiffID()
pd.pushState.Lock()
if descriptor, ok := pd.pushState.remoteLayers[diffID]; ok {
// it is already known that the push is not needed and
// therefore doing a stat is unnecessary
pd.pushState.Unlock()
progress.Update(progressOutput, pd.ID(), "Layer already exists")
return descriptor, nil
}
pd.pushState.Unlock()
maxMountAttempts, maxExistenceChecks, checkOtherRepositories := getMaxMountAndExistenceCheckAttempts(pd.layer)
// Do we have any metadata associated with this layer's DiffID?
v2Metadata, err := pd.v2MetadataService.GetMetadata(diffID)
if err == nil {
// check for blob existence in the target repository if we have a mapping with it
descriptor, exists, err := pd.layerAlreadyExists(ctx, progressOutput, diffID, false, 1, v2Metadata)
if exists || err != nil {
return descriptor, err
}
}
// if digest was empty or not saved, or if blob does not exist on the remote repository,
// then push the blob.
bs := pd.repo.Blobs(ctx)
var layerUpload distribution.BlobWriter
// Attempt to find another repository in the same registry to mount the layer from to avoid an unnecessary upload
candidates := getRepositoryMountCandidates(pd.repoInfo, pd.hmacKey, maxMountAttempts, v2Metadata)
for _, mountCandidate := range candidates {
logrus.Debugf("attempting to mount layer %s (%s) from %s", diffID, mountCandidate.Digest, mountCandidate.SourceRepository)
createOpts := []distribution.BlobCreateOption{}
if len(mountCandidate.SourceRepository) > 0 {
namedRef, err := reference.WithName(mountCandidate.SourceRepository)
if err != nil {
logrus.Errorf("failed to parse source repository reference %v: %v", namedRef.String(), err)
pd.v2MetadataService.Remove(mountCandidate)
continue
}
// TODO (brianbland): We need to construct a reference where the Name is
// only the full remote name, so clean this up when distribution has a
// richer reference package
remoteRef, err := distreference.WithName(namedRef.RemoteName())
if err != nil {
logrus.Errorf("failed to make remote reference out of %q: %v", namedRef.RemoteName(), namedRef.RemoteName())
continue
}
canonicalRef, err := distreference.WithDigest(distreference.TrimNamed(remoteRef), mountCandidate.Digest)
if err != nil {
logrus.Errorf("failed to make canonical reference: %v", err)
continue
}
createOpts = append(createOpts, client.WithMountFrom(canonicalRef))
}
// send the layer
lu, err := bs.Create(ctx, createOpts...)
switch err := err.(type) {
case nil:
// noop
case distribution.ErrBlobMounted:
progress.Updatef(progressOutput, pd.ID(), "Mounted from %s", err.From.Name())
err.Descriptor.MediaType = schema2.MediaTypeLayer
pd.pushState.Lock()
pd.pushState.confirmedV2 = true
pd.pushState.remoteLayers[diffID] = err.Descriptor
pd.pushState.Unlock()
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.TagAndAdd(diffID, pd.hmacKey, metadata.V2Metadata{
Digest: err.Descriptor.Digest,
SourceRepository: pd.repoInfo.FullName(),
}); err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
return err.Descriptor, nil
default:
logrus.Infof("failed to mount layer %s (%s) from %s: %v", diffID, mountCandidate.Digest, mountCandidate.SourceRepository, err)
}
if len(mountCandidate.SourceRepository) > 0 &&
(metadata.CheckV2MetadataHMAC(&mountCandidate, pd.hmacKey) ||
len(mountCandidate.HMAC) == 0) {
cause := "blob mount failure"
if err != nil {
cause = fmt.Sprintf("an error: %v", err.Error())
}
logrus.Debugf("removing association between layer %s and %s due to %s", mountCandidate.Digest, mountCandidate.SourceRepository, cause)
pd.v2MetadataService.Remove(mountCandidate)
}
if lu != nil {
// cancel previous upload
cancelLayerUpload(ctx, mountCandidate.Digest, layerUpload)
layerUpload = lu
}
}
if maxExistenceChecks-len(pd.checkedDigests) > 0 {
// do additional layer existence checks with other known digests if any
descriptor, exists, err := pd.layerAlreadyExists(ctx, progressOutput, diffID, checkOtherRepositories, maxExistenceChecks-len(pd.checkedDigests), v2Metadata)
if exists || err != nil {
return descriptor, err
}
}
logrus.Debugf("Pushing layer: %s", diffID)
if layerUpload == nil {
layerUpload, err = bs.Create(ctx)
if err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
}
defer layerUpload.Close()
// upload the blob
desc, err := pd.uploadUsingSession(ctx, progressOutput, diffID, layerUpload)
if err != nil {
return desc, err
}
return desc, nil
}
// DownloadLayers ensures layers end up in the portlayer's image store
// It handles existing and simultaneous layer download de-duplication
// This code is utilizes Docker's xfer package: https://github.com/docker/docker/tree/v1.11.2/distribution/xfer
func (ldm *LayerDownloader) DownloadLayers(ctx context.Context, ic *ImageC) error {
defer trace.End(trace.Begin(""))
var (
topDownload *downloadTransfer
watcher *xfer.Watcher
d xfer.Transfer
layerCount = 0
sf = streamformatter.NewJSONStreamFormatter()
progressOutput = &serialProgressOutput{
c: make(chan prog, 100),
out: sf.NewProgressOutput(ic.Outstream, false),
}
)
go progressOutput.run()
defer progressOutput.stop()
// lock here so that we get all layers in flight before another client comes along
ldm.m.Lock()
// Grab the imageLayers
layers := ic.ImageLayers
// iterate backwards through layers to download
for i := len(layers) - 1; i >= 0; i-- {
layer := layers[i]
id := layer.ID
layerConfig, err := LayerCache().Get(id)
if err != nil {
switch err := err.(type) {
case LayerNotFoundError:
layerCount++
// layer does not already exist in store and is not currently in flight, so download it
progress.Update(progressOutput, layer.String(), "Pulling fs layer")
xferFunc := ldm.makeDownloadFunc(layer, ic, topDownload, layers)
d, watcher = ldm.tm.Transfer(id, xferFunc, progressOutput)
topDownload = d.(*downloadTransfer)
defer topDownload.Transfer.Release(watcher)
ldm.registerDownload(topDownload)
layer.Downloading = true
LayerCache().Add(layer)
continue
default:
return err
}
}
if layerConfig.Downloading {
layerCount++
if existingDownload, ok := ldm.downloadsByID[id]; ok {
xferFunc := ldm.makeDownloadFuncFromDownload(layer, existingDownload, topDownload, layers)
d, watcher = ldm.tm.Transfer(id, xferFunc, progressOutput)
topDownload = d.(*downloadTransfer)
defer topDownload.Transfer.Release(watcher)
}
continue
}
progress.Update(progressOutput, layer.String(), "Already exists")
}
ldm.m.Unlock()
// each layer download will block until the parent download finishes,
// so this will block until the child-most layer, and thus all layers, have finished downloading
if layerCount > 0 {
select {
case <-ctx.Done():
return ctx.Err()
case <-topDownload.Done():
default:
<-topDownload.Done()
}
err := topDownload.result()
if err != nil {
return err
}
} else {
if err := updateRepositoryCache(ic); err != nil {
return err
}
}
progress.Message(progressOutput, "", "Digest: "+ic.ImageManifest.Digest)
if layerCount > 0 {
progress.Message(progressOutput, "", "Status: Downloaded newer image for "+ic.Image+":"+ic.Tag)
} else {
progress.Message(progressOutput, "", "Status: Image is up to date for "+ic.Image+":"+ic.Tag)
}
return nil
}
func (p *v1Puller) pullImage(ctx context.Context, v1ID, endpoint string, localNameRef reference.Named, layersDownloaded *bool) (err error) {
var history []string
history, err = p.session.GetRemoteHistory(v1ID, endpoint)
if err != nil {
return err
}
if len(history) < 1 {
return fmt.Errorf("empty history for image %s", v1ID)
}
progress.Update(p.config.ProgressOutput, stringid.TruncateID(v1ID), "Pulling dependent layers")
var (
descriptors []xfer.DownloadDescriptor
newHistory []image.History
imgJSON []byte
imgSize int64
)
// Iterate over layers, in order from bottom-most to top-most. Download
// config for all layers and create descriptors.
for i := len(history) - 1; i >= 0; i-- {
v1LayerID := history[i]
imgJSON, imgSize, err = p.downloadLayerConfig(v1LayerID, endpoint)
if err != nil {
return err
}
// Create a new-style config from the legacy configs
h, err := v1.HistoryFromConfig(imgJSON, false)
if err != nil {
return err
}
newHistory = append(newHistory, h)
layerDescriptor := &v1LayerDescriptor{
v1LayerID: v1LayerID,
indexName: p.repoInfo.Index.Name,
endpoint: endpoint,
v1IDService: p.v1IDService,
layersDownloaded: layersDownloaded,
layerSize: imgSize,
session: p.session,
}
descriptors = append(descriptors, layerDescriptor)
}
rootFS := image.NewRootFS()
resultRootFS, release, err := p.config.DownloadManager.Download(ctx, *rootFS, descriptors, p.config.ProgressOutput)
if err != nil {
return err
}
defer release()
config, err := v1.MakeConfigFromV1Config(imgJSON, &resultRootFS, newHistory)
if err != nil {
return err
}
imageID, err := p.config.ImageStore.Create(config)
if err != nil {
return err
}
if err := p.config.ReferenceStore.AddTag(localNameRef, imageID, true); err != nil {
return err
}
return nil
}
func (pd *v2PushDescriptor) Upload(ctx context.Context, progressOutput progress.Output) error {
diffID := pd.DiffID()
pd.pushState.Lock()
if _, ok := pd.pushState.remoteLayers[diffID]; ok {
// it is already known that the push is not needed and
// therefore doing a stat is unnecessary
pd.pushState.Unlock()
progress.Update(progressOutput, pd.ID(), "Layer already exists")
return nil
}
pd.pushState.Unlock()
// Do we have any metadata associated with this layer's DiffID?
v2Metadata, err := pd.v2MetadataService.GetMetadata(diffID)
if err == nil {
descriptor, exists, err := layerAlreadyExists(ctx, v2Metadata, pd.repoInfo, pd.repo, pd.pushState)
if err != nil {
progress.Update(progressOutput, pd.ID(), "Image push failed")
return retryOnError(err)
}
if exists {
progress.Update(progressOutput, pd.ID(), "Layer already exists")
pd.pushState.Lock()
pd.pushState.remoteLayers[diffID] = descriptor
pd.pushState.Unlock()
return nil
}
}
logrus.Debugf("Pushing layer: %s", diffID)
// if digest was empty or not saved, or if blob does not exist on the remote repository,
// then push the blob.
bs := pd.repo.Blobs(ctx)
var mountFrom metadata.V2Metadata
// Attempt to find another repository in the same registry to mount the layer from to avoid an unnecessary upload
for _, metadata := range v2Metadata {
sourceRepo, err := reference.ParseNamed(metadata.SourceRepository)
if err != nil {
continue
}
if pd.repoInfo.Hostname() == sourceRepo.Hostname() {
logrus.Debugf("attempting to mount layer %s (%s) from %s", diffID, metadata.Digest, sourceRepo.FullName())
mountFrom = metadata
break
}
}
var createOpts []distribution.BlobCreateOption
if mountFrom.SourceRepository != "" {
namedRef, err := reference.WithName(mountFrom.SourceRepository)
if err != nil {
return err
}
// TODO (brianbland): We need to construct a reference where the Name is
// only the full remote name, so clean this up when distribution has a
// richer reference package
remoteRef, err := distreference.WithName(namedRef.RemoteName())
if err != nil {
return err
}
canonicalRef, err := distreference.WithDigest(remoteRef, mountFrom.Digest)
if err != nil {
return err
}
createOpts = append(createOpts, client.WithMountFrom(canonicalRef))
}
// Send the layer
layerUpload, err := bs.Create(ctx, createOpts...)
switch err := err.(type) {
case distribution.ErrBlobMounted:
progress.Updatef(progressOutput, pd.ID(), "Mounted from %s", err.From.Name())
err.Descriptor.MediaType = schema2.MediaTypeLayer
pd.pushState.Lock()
pd.pushState.confirmedV2 = true
pd.pushState.remoteLayers[diffID] = err.Descriptor
pd.pushState.Unlock()
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.Add(diffID, metadata.V2Metadata{Digest: mountFrom.Digest, SourceRepository: pd.repoInfo.FullName()}); err != nil {
return xfer.DoNotRetry{Err: err}
}
return nil
}
if mountFrom.SourceRepository != "" {
// unable to mount layer from this repository, so this source mapping is no longer valid
logrus.Debugf("unassociating layer %s (%s) with %s", diffID, mountFrom.Digest, mountFrom.SourceRepository)
pd.v2MetadataService.Remove(mountFrom)
}
if err != nil {
return retryOnError(err)
}
defer layerUpload.Close()
arch, err := pd.layer.TarStream()
if err != nil {
return xfer.DoNotRetry{Err: err}
}
// don't care if this fails; best effort
size, _ := pd.layer.DiffSize()
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, arch), progressOutput, size, pd.ID(), "Pushing")
compressedReader, compressionDone := compress(reader)
defer func() {
reader.Close()
<-compressionDone
}()
digester := digest.Canonical.New()
tee := io.TeeReader(compressedReader, digester.Hash())
nn, err := layerUpload.ReadFrom(tee)
compressedReader.Close()
if err != nil {
return retryOnError(err)
}
pushDigest := digester.Digest()
if _, err := layerUpload.Commit(ctx, distribution.Descriptor{Digest: pushDigest}); err != nil {
return retryOnError(err)
}
logrus.Debugf("uploaded layer %s (%s), %d bytes", diffID, pushDigest, nn)
progress.Update(progressOutput, pd.ID(), "Pushed")
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.Add(diffID, metadata.V2Metadata{Digest: pushDigest, SourceRepository: pd.repoInfo.FullName()}); err != nil {
return xfer.DoNotRetry{Err: err}
}
pd.pushState.Lock()
// If Commit succeded, that's an indication that the remote registry
// speaks the v2 protocol.
pd.pushState.confirmedV2 = true
pd.pushState.remoteLayers[diffID] = distribution.Descriptor{
Digest: pushDigest,
MediaType: schema2.MediaTypeLayer,
Size: nn,
}
pd.pushState.Unlock()
return nil
}
func (ld *v2LayerDescriptor) Download(ctx context.Context, progressOutput progress.Output) (io.ReadCloser, int64, error) {
logrus.Debugf("pulling blob %q", ld.digest)
var (
err error
offset int64
)
if ld.tmpFile == nil {
ld.tmpFile, err = createDownloadFile()
if err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
} else {
offset, err = ld.tmpFile.Seek(0, os.SEEK_END)
if err != nil {
logrus.Debugf("error seeking to end of download file: %v", err)
offset = 0
ld.tmpFile.Close()
if err := os.Remove(ld.tmpFile.Name()); err != nil {
logrus.Errorf("Failed to remove temp file: %s", ld.tmpFile.Name())
}
ld.tmpFile, err = createDownloadFile()
if err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
} else if offset != 0 {
logrus.Debugf("attempting to resume download of %q from %d bytes", ld.digest, offset)
}
}
tmpFile := ld.tmpFile
layerDownload, err := ld.open(ctx)
if err != nil {
logrus.Errorf("Error initiating layer download: %v", err)
if err == distribution.ErrBlobUnknown {
return nil, 0, xfer.DoNotRetry{Err: err}
}
return nil, 0, retryOnError(err)
}
if offset != 0 {
_, err := layerDownload.Seek(offset, os.SEEK_SET)
if err != nil {
if err := ld.truncateDownloadFile(); err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
return nil, 0, err
}
}
size, err := layerDownload.Seek(0, os.SEEK_END)
if err != nil {
// Seek failed, perhaps because there was no Content-Length
// header. This shouldn't fail the download, because we can
// still continue without a progress bar.
size = 0
} else {
if size != 0 && offset > size {
logrus.Debug("Partial download is larger than full blob. Starting over")
offset = 0
if err := ld.truncateDownloadFile(); err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
}
// Restore the seek offset either at the beginning of the
// stream, or just after the last byte we have from previous
// attempts.
_, err = layerDownload.Seek(offset, os.SEEK_SET)
if err != nil {
return nil, 0, err
}
}
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, layerDownload), progressOutput, size-offset, ld.ID(), "Downloading")
defer reader.Close()
if ld.verifier == nil {
ld.verifier, err = digest.NewDigestVerifier(ld.digest)
if err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
}
_, err = io.Copy(tmpFile, io.TeeReader(reader, ld.verifier))
if err != nil {
if err == transport.ErrWrongCodeForByteRange {
if err := ld.truncateDownloadFile(); err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
return nil, 0, err
}
return nil, 0, retryOnError(err)
}
progress.Update(progressOutput, ld.ID(), "Verifying Checksum")
if !ld.verifier.Verified() {
err = fmt.Errorf("filesystem layer verification failed for digest %s", ld.digest)
logrus.Error(err)
// Allow a retry if this digest verification error happened
// after a resumed download.
if offset != 0 {
if err := ld.truncateDownloadFile(); err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
return nil, 0, err
}
return nil, 0, xfer.DoNotRetry{Err: err}
}
progress.Update(progressOutput, ld.ID(), "Download complete")
logrus.Debugf("Downloaded %s to tempfile %s", ld.ID(), tmpFile.Name())
_, err = tmpFile.Seek(0, os.SEEK_SET)
if err != nil {
tmpFile.Close()
if err := os.Remove(tmpFile.Name()); err != nil {
logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
}
ld.tmpFile = nil
ld.verifier = nil
return nil, 0, xfer.DoNotRetry{Err: err}
}
// hand off the temporary file to the download manager, so it will only
// be closed once
ld.tmpFile = nil
return ioutils.NewReadCloserWrapper(tmpFile, func() error {
tmpFile.Close()
err := os.RemoveAll(tmpFile.Name())
if err != nil {
logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
}
return err
}), size, nil
}
// makeDownloadFunc returns a func used by xfer.TransferManager to download a layer
func (ldm *LayerDownloader) makeDownloadFunc(layer *ImageWithMeta, ic *ImageC, parentDownload *downloadTransfer, layers []*ImageWithMeta) xfer.DoFunc {
return func(progressChan chan<- progress.Progress, start <-chan struct{}, inactive chan<- struct{}) xfer.Transfer {
d := &downloadTransfer{
Transfer: xfer.NewTransfer(),
layer: layer,
}
go func() {
defer func() {
close(progressChan)
// remove layer from cache if there was an error attempting to download
if d.err != nil {
LayerCache().Remove(layer.ID)
}
}()
progressOutput := progress.ChanOutput(progressChan)
// wait for TransferManager to give the go-ahead
select {
case <-start:
default:
progress.Update(progressOutput, layer.String(), "Waiting")
<-start
}
if parentDownload != nil {
// bail if parent download failed or was cancelled
select {
case <-parentDownload.Done():
if err := parentDownload.result(); err != nil {
d.err = err
return
}
default:
}
}
// fetch blob
diffID, err := FetchImageBlob(d.Transfer.Context(), ic.Options, layer, progressOutput)
if err != nil {
d.err = fmt.Errorf("%s/%s returned %s", ic.Image, layer.ID, err)
return
}
layer.DiffID = diffID
close(inactive)
if parentDownload != nil {
select {
case <-d.Transfer.Context().Done():
d.err = errors.New("layer download cancelled")
return
default:
<-parentDownload.Done() // block until parent download completes
}
if err := parentDownload.result(); err != nil {
d.err = err
return
}
}
// is this the leaf layer?
imageLayer := layer.ID == layers[0].ID
// if this is the leaf layer, we are done and can now create the image config
if imageLayer {
imageConfig, err := ic.CreateImageConfig(layers)
if err != nil {
d.err = err
return
}
// cache and persist the image
cache.ImageCache().Add(&imageConfig)
cache.ImageCache().Save()
// place calculated ImageID in struct
ic.ImageID = imageConfig.ImageID
if err = updateRepositoryCache(ic); err != nil {
d.err = err
return
}
}
ldm.m.Lock()
defer ldm.m.Unlock()
// Write blob to the storage layer
if err := ic.WriteImageBlob(layer, progressOutput, imageLayer); err != nil {
d.err = err
return
}
// mark the layer as finished downloading
LayerCache().Commit(layer)
ldm.unregisterDownload(layer)
}()
return d
}
}
// FetchImageBlob fetches the image blob
func FetchImageBlob(ctx context.Context, options Options, image *ImageWithMeta, progressOutput progress.Output) (string, error) {
defer trace.End(trace.Begin(options.Image + "/" + image.Layer.BlobSum))
id := image.ID
layer := image.Layer.BlobSum
meta := image.Meta
diffID := ""
url, err := url.Parse(options.Registry)
if err != nil {
return diffID, err
}
url.Path = path.Join(url.Path, options.Image, "blobs", layer)
log.Debugf("URL: %s\n ", url)
fetcher := urlfetcher.NewURLFetcher(urlfetcher.Options{
Timeout: options.Timeout,
Username: options.Username,
Password: options.Password,
Token: options.Token,
InsecureSkipVerify: options.InsecureSkipVerify,
})
// ctx
ctx, cancel := context.WithTimeout(ctx, options.Timeout)
defer cancel()
imageFileName, err := fetcher.Fetch(ctx, url, true, progressOutput, image.String())
if err != nil {
return diffID, err
}
// Cleanup function for the error case
defer func() {
if err != nil {
os.Remove(imageFileName)
}
}()
// Open the file so that we can use it as a io.Reader for sha256 calculation
imageFile, err := os.Open(string(imageFileName))
if err != nil {
return diffID, err
}
defer imageFile.Close()
// blobSum is the sha of the compressed layer
blobSum := sha256.New()
// diffIDSum is the sha of the uncompressed layer
diffIDSum := sha256.New()
// blobTr is an io.TeeReader that writes bytes to blobSum that it reads from imageFile
// see https://golang.org/pkg/io/#TeeReader
blobTr := io.TeeReader(imageFile, blobSum)
progress.Update(progressOutput, image.String(), "Verifying Checksum")
decompressedTar, err := archive.DecompressStream(blobTr)
if err != nil {
return diffID, err
}
// Copy bytes from decompressed layer into diffIDSum to calculate diffID
_, cerr := io.Copy(diffIDSum, decompressedTar)
if cerr != nil {
return diffID, cerr
}
bs := fmt.Sprintf("sha256:%x", blobSum.Sum(nil))
if bs != layer {
return diffID, fmt.Errorf("Failed to validate layer checksum. Expected %s got %s", layer, bs)
}
diffID = fmt.Sprintf("sha256:%x", diffIDSum.Sum(nil))
// this isn't an empty layer, so we need to calculate the size
if diffID != string(DigestSHA256EmptyTar) {
var layerSize int64
// seek to the beginning of the file
imageFile.Seek(0, 0)
// recreate the decompressed tar Reader
decompressedTar, err := archive.DecompressStream(imageFile)
if err != nil {
return "", err
}
// get a tar reader for access to the files in the archive
tr := tar.NewReader(decompressedTar)
// iterate through tar headers to get file sizes
for {
tarHeader, err := tr.Next()
if err == io.EOF {
break
}
if err != nil {
return "", err
}
layerSize += tarHeader.Size
}
image.Size = layerSize
}
log.Infof("diffID for layer %s: %s", id, diffID)
// Ensure the parent directory exists
destination := path.Join(DestinationDirectory(options), id)
err = os.MkdirAll(destination, 0755) /* #nosec */
if err != nil {
return diffID, err
}
// Move(rename) the temporary file to its final destination
err = os.Rename(string(imageFileName), path.Join(destination, id+".tar"))
if err != nil {
return diffID, err
}
// Dump the history next to it
err = ioutil.WriteFile(path.Join(destination, id+".json"), []byte(meta), 0644)
if err != nil {
return diffID, err
}
progress.Update(progressOutput, image.String(), "Download complete")
return diffID, nil
}
func (pd *v2PushDescriptor) Upload(ctx context.Context, progressOutput progress.Output) (distribution.Descriptor, error) {
if fs, ok := pd.layer.(distribution.Describable); ok {
if d := fs.Descriptor(); len(d.URLs) > 0 {
progress.Update(progressOutput, pd.ID(), "Skipped foreign layer")
return d, nil
}
}
diffID := pd.DiffID()
pd.pushState.Lock()
if descriptor, ok := pd.pushState.remoteLayers[diffID]; ok {
// it is already known that the push is not needed and
// therefore doing a stat is unnecessary
pd.pushState.Unlock()
progress.Update(progressOutput, pd.ID(), "Layer already exists")
return descriptor, nil
}
pd.pushState.Unlock()
// Do we have any metadata associated with this layer's DiffID?
v2Metadata, err := pd.v2MetadataService.GetMetadata(diffID)
if err == nil {
descriptor, exists, err := layerAlreadyExists(ctx, v2Metadata, pd.repoInfo, pd.repo, pd.pushState)
if err != nil {
progress.Update(progressOutput, pd.ID(), "Image push failed")
return distribution.Descriptor{}, retryOnError(err)
}
if exists {
progress.Update(progressOutput, pd.ID(), "Layer already exists")
pd.pushState.Lock()
pd.pushState.remoteLayers[diffID] = descriptor
pd.pushState.Unlock()
return descriptor, nil
}
}
logrus.Debugf("Pushing layer: %s", diffID)
// if digest was empty or not saved, or if blob does not exist on the remote repository,
// then push the blob.
bs := pd.repo.Blobs(ctx)
var layerUpload distribution.BlobWriter
mountAttemptsRemaining := 3
// Attempt to find another repository in the same registry to mount the layer
// from to avoid an unnecessary upload.
// Note: metadata is stored from oldest to newest, so we iterate through this
// slice in reverse to maximize our chances of the blob still existing in the
// remote repository.
for i := len(v2Metadata) - 1; i >= 0 && mountAttemptsRemaining > 0; i-- {
mountFrom := v2Metadata[i]
sourceRepo, err := reference.ParseNamed(mountFrom.SourceRepository)
if err != nil {
continue
}
if pd.repoInfo.Hostname() != sourceRepo.Hostname() {
// don't mount blobs from another registry
continue
}
namedRef, err := reference.WithName(mountFrom.SourceRepository)
if err != nil {
continue
}
// TODO (brianbland): We need to construct a reference where the Name is
// only the full remote name, so clean this up when distribution has a
// richer reference package
remoteRef, err := distreference.WithName(namedRef.RemoteName())
if err != nil {
continue
}
canonicalRef, err := distreference.WithDigest(remoteRef, mountFrom.Digest)
if err != nil {
continue
}
logrus.Debugf("attempting to mount layer %s (%s) from %s", diffID, mountFrom.Digest, sourceRepo.FullName())
layerUpload, err = bs.Create(ctx, client.WithMountFrom(canonicalRef))
switch err := err.(type) {
case distribution.ErrBlobMounted:
progress.Updatef(progressOutput, pd.ID(), "Mounted from %s", err.From.Name())
err.Descriptor.MediaType = schema2.MediaTypeLayer
pd.pushState.Lock()
pd.pushState.confirmedV2 = true
pd.pushState.remoteLayers[diffID] = err.Descriptor
pd.pushState.Unlock()
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.Add(diffID, metadata.V2Metadata{Digest: mountFrom.Digest, SourceRepository: pd.repoInfo.FullName()}); err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
return err.Descriptor, nil
case nil:
// blob upload session created successfully, so begin the upload
mountAttemptsRemaining = 0
default:
// unable to mount layer from this repository, so this source mapping is no longer valid
logrus.Debugf("unassociating layer %s (%s) with %s", diffID, mountFrom.Digest, mountFrom.SourceRepository)
pd.v2MetadataService.Remove(mountFrom)
mountAttemptsRemaining--
}
}
if layerUpload == nil {
layerUpload, err = bs.Create(ctx)
if err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
}
defer layerUpload.Close()
arch, err := pd.layer.TarStream()
if err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
// don't care if this fails; best effort
size, _ := pd.layer.DiffSize()
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, arch), progressOutput, size, pd.ID(), "Pushing")
compressedReader, compressionDone := compress(reader)
defer func() {
reader.Close()
<-compressionDone
}()
digester := digest.Canonical.New()
tee := io.TeeReader(compressedReader, digester.Hash())
nn, err := layerUpload.ReadFrom(tee)
compressedReader.Close()
if err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
pushDigest := digester.Digest()
if _, err := layerUpload.Commit(ctx, distribution.Descriptor{Digest: pushDigest}); err != nil {
return distribution.Descriptor{}, retryOnError(err)
}
logrus.Debugf("uploaded layer %s (%s), %d bytes", diffID, pushDigest, nn)
progress.Update(progressOutput, pd.ID(), "Pushed")
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.Add(diffID, metadata.V2Metadata{Digest: pushDigest, SourceRepository: pd.repoInfo.FullName()}); err != nil {
return distribution.Descriptor{}, xfer.DoNotRetry{Err: err}
}
pd.pushState.Lock()
// If Commit succeeded, that's an indication that the remote registry
// speaks the v2 protocol.
pd.pushState.confirmedV2 = true
descriptor := distribution.Descriptor{
Digest: pushDigest,
MediaType: schema2.MediaTypeLayer,
Size: nn,
}
pd.pushState.remoteLayers[diffID] = descriptor
pd.pushState.Unlock()
return descriptor, nil
}
// makeDownloadFunc returns a function that performs the layer download and
// registration. If parentDownload is non-nil, it waits for that download to
// complete before the registration step, and registers the downloaded data
// on top of parentDownload's resulting layer. Otherwise, it registers the
// layer on top of the ChainID given by parentLayer.
func (ldm *LayerDownloadManager) makeDownloadFunc(descriptor DownloadDescriptor, parentLayer layer.ChainID, parentDownload *downloadTransfer) DoFunc {
return func(progressChan chan<- progress.Progress, start <-chan struct{}, inactive chan<- struct{}) Transfer {
d := &downloadTransfer{
Transfer: NewTransfer(),
layerStore: ldm.layerStore,
}
go func() {
defer func() {
close(progressChan)
}()
progressOutput := progress.ChanOutput(progressChan)
select {
case <-start:
default:
progress.Update(progressOutput, descriptor.ID(), "Waiting")
<-start
}
if parentDownload != nil {
// Did the parent download already fail or get
// cancelled?
select {
case <-parentDownload.Done():
_, err := parentDownload.result()
if err != nil {
d.err = err
return
}
default:
}
}
var (
downloadReader io.ReadCloser
size int64
err error
retries int
)
defer descriptor.Close()
for {
downloadReader, size, err = descriptor.Download(d.Transfer.Context(), progressOutput)
if err == nil {
break
}
// If an error was returned because the context
// was cancelled, we shouldn't retry.
select {
case <-d.Transfer.Context().Done():
d.err = err
return
default:
}
retries++
if _, isDNR := err.(DoNotRetry); isDNR || retries == maxDownloadAttempts {
logrus.Errorf("Download failed: %v", err)
d.err = err
return
}
logrus.Errorf("Download failed, retrying: %v", err)
delay := retries * 5
ticker := time.NewTicker(time.Second)
selectLoop:
for {
progress.Updatef(progressOutput, descriptor.ID(), "Retrying in %d second%s", delay, (map[bool]string{true: "s"})[delay != 1])
select {
case <-ticker.C:
delay--
if delay == 0 {
ticker.Stop()
break selectLoop
}
case <-d.Transfer.Context().Done():
ticker.Stop()
d.err = errors.New("download cancelled during retry delay")
return
}
}
}
close(inactive)
if parentDownload != nil {
select {
case <-d.Transfer.Context().Done():
d.err = errors.New("layer registration cancelled")
downloadReader.Close()
return
case <-parentDownload.Done():
}
l, err := parentDownload.result()
if err != nil {
d.err = err
downloadReader.Close()
return
}
parentLayer = l.ChainID()
}
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(d.Transfer.Context(), downloadReader), progressOutput, size, descriptor.ID(), "Extracting")
defer reader.Close()
inflatedLayerData, err := archive.DecompressStream(reader)
if err != nil {
d.err = fmt.Errorf("could not get decompression stream: %v", err)
return
}
var src distribution.Descriptor
if fs, ok := descriptor.(distribution.Describable); ok {
src = fs.Descriptor()
}
if ds, ok := d.layerStore.(layer.DescribableStore); ok {
d.layer, err = ds.RegisterWithDescriptor(inflatedLayerData, parentLayer, src)
} else {
d.layer, err = d.layerStore.Register(inflatedLayerData, parentLayer)
}
if err != nil {
select {
case <-d.Transfer.Context().Done():
d.err = errors.New("layer registration cancelled")
default:
d.err = fmt.Errorf("failed to register layer: %v", err)
}
return
}
progress.Update(progressOutput, descriptor.ID(), "Pull complete")
withRegistered, hasRegistered := descriptor.(DownloadDescriptorWithRegistered)
if hasRegistered {
withRegistered.Registered(d.layer.DiffID())
}
// Doesn't actually need to be its own goroutine, but
// done like this so we can defer close(c).
go func() {
<-d.Transfer.Released()
if d.layer != nil {
layer.ReleaseAndLog(d.layerStore, d.layer)
}
}()
}()
return d
}
}
func (ld *v2LayerDescriptor) Download(ctx context.Context, progressOutput progress.Output) (io.ReadCloser, int64, error) {
logrus.Debugf("pulling blob %q", ld.digest)
blobs := ld.repo.Blobs(ctx)
layerDownload, err := blobs.Open(ctx, ld.digest)
if err != nil {
logrus.Debugf("Error statting layer: %v", err)
if err == distribution.ErrBlobUnknown {
return nil, 0, xfer.DoNotRetry{Err: err}
}
return nil, 0, retryOnError(err)
}
size, err := layerDownload.Seek(0, os.SEEK_END)
if err != nil {
// Seek failed, perhaps because there was no Content-Length
// header. This shouldn't fail the download, because we can
// still continue without a progress bar.
size = 0
} else {
// Restore the seek offset at the beginning of the stream.
_, err = layerDownload.Seek(0, os.SEEK_SET)
if err != nil {
return nil, 0, err
}
}
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, layerDownload), progressOutput, size, ld.ID(), "Downloading")
defer reader.Close()
verifier, err := digest.NewDigestVerifier(ld.digest)
if err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
tmpFile, err := ioutil.TempFile("", "GetImageBlob")
if err != nil {
return nil, 0, xfer.DoNotRetry{Err: err}
}
_, err = io.Copy(tmpFile, io.TeeReader(reader, verifier))
if err != nil {
return nil, 0, retryOnError(err)
}
progress.Update(progressOutput, ld.ID(), "Verifying Checksum")
if !verifier.Verified() {
err = fmt.Errorf("filesystem layer verification failed for digest %s", ld.digest)
logrus.Error(err)
tmpFile.Close()
if err := os.RemoveAll(tmpFile.Name()); err != nil {
logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
}
return nil, 0, xfer.DoNotRetry{Err: err}
}
progress.Update(progressOutput, ld.ID(), "Download complete")
logrus.Debugf("Downloaded %s to tempfile %s", ld.ID(), tmpFile.Name())
tmpFile.Seek(0, 0)
return ioutils.NewReadCloserWrapper(tmpFile, tmpFileCloser(tmpFile)), size, nil
}
// ImagesToDownload creates a slice of ImageWithMeta for the images that needs to be downloaded
func ImagesToDownload(manifest *Manifest, storeName string) ([]*ImageWithMeta, *ImageWithMeta, error) {
images := make([]*ImageWithMeta, len(manifest.FSLayers))
v1 := docker.V1Image{}
// iterate from parent to children
for i := len(manifest.History) - 1; i >= 0; i-- {
history := manifest.History[i]
layer := manifest.FSLayers[i]
// unmarshall V1Compatibility to get the image ID
if err := json.Unmarshal([]byte(history.V1Compatibility), &v1); err != nil {
return nil, nil, fmt.Errorf("Failed to unmarshall image history: %s", err)
}
// if parent is empty set it to scratch
parent := "scratch"
if v1.Parent != "" {
parent = v1.Parent
}
// add image to ImageWithMeta list
images[i] = &ImageWithMeta{
Image: &models.Image{
ID: v1.ID,
Parent: &parent,
Store: storeName,
},
meta: history.V1Compatibility,
layer: layer,
diffID: "",
}
log.Debugf("ImagesToDownload Manifest image: %#v", images[i])
}
// return early if -standalone set
if options.standalone {
return images, nil, nil
}
// Create the image store just in case
err := CreateImageStore(storeName)
if err != nil {
return nil, nil, fmt.Errorf("Failed to create image store: %s", err)
}
// Get the list of known images from the storage layer
existingImages, err := ListImages(storeName, images)
if err != nil {
return nil, nil, fmt.Errorf("Failed to obtain list of images: %s", err)
}
for i := range existingImages {
log.Debugf("Existing image: %#v", existingImages[i])
}
// grab the imageLayer for use in later evaluation of metadata update
imageLayer := images[0]
// iterate from parent to children
// so that we can delete from the slice
// while iterating over it
for i := len(images) - 1; i >= 0; i-- {
ID := images[i].ID
// Check whether storage layer knows this image ID
if _, ok := existingImages[ID]; ok {
log.Debugf("%s already exists", ID)
// update the progress before deleting it from the slice
progress.Update(po, images[i].String(), "Already exists")
// delete existing image from images
images = append(images[:i], images[i+1:]...)
}
}
return images, imageLayer, nil
}
func (lum *LayerUploadManager) makeUploadFunc(descriptor UploadDescriptor) DoFunc {
return func(progressChan chan<- progress.Progress, start <-chan struct{}, inactive chan<- struct{}) Transfer {
u := &uploadTransfer{
Transfer: NewTransfer(),
}
go func() {
defer func() {
close(progressChan)
}()
progressOutput := progress.ChanOutput(progressChan)
select {
case <-start:
default:
progress.Update(progressOutput, descriptor.ID(), "Waiting")
<-start
}
retries := 0
for {
remoteDescriptor, err := descriptor.Upload(u.Transfer.Context(), progressOutput)
if err == nil {
u.remoteDescriptor = remoteDescriptor
break
}
// If an error was returned because the context
// was cancelled, we shouldn't retry.
select {
case <-u.Transfer.Context().Done():
u.err = err
return
default:
}
retries++
if _, isDNR := err.(DoNotRetry); isDNR || retries == maxUploadAttempts {
logrus.Errorf("Upload failed: %v", err)
u.err = err
return
}
logrus.Errorf("Upload failed, retrying: %v", err)
delay := retries * 5
ticker := time.NewTicker(time.Second)
selectLoop:
for {
progress.Updatef(progressOutput, descriptor.ID(), "Retrying in %d second%s", delay, (map[bool]string{true: "s"})[delay != 1])
select {
case <-ticker.C:
delay--
if delay == 0 {
ticker.Stop()
break selectLoop
}
case <-u.Transfer.Context().Done():
ticker.Stop()
u.err = errors.New("upload cancelled during retry delay")
return
}
}
}
}()
return u
}
}
// layerAlreadyExists checks if the registry already knows about any of the metadata passed in the "metadata"
// slice. If it finds one that the registry knows about, it returns the known digest and "true". If
// "checkOtherRepositories" is true, stat will be performed also with digests mapped to any other repository
// (not just the target one).
func (pd *v2PushDescriptor) layerAlreadyExists(
ctx context.Context,
progressOutput progress.Output,
diffID layer.DiffID,
checkOtherRepositories bool,
maxExistenceCheckAttempts int,
v2Metadata []metadata.V2Metadata,
) (desc distribution.Descriptor, exists bool, err error) {
// filter the metadata
candidates := []metadata.V2Metadata{}
for _, meta := range v2Metadata {
if len(meta.SourceRepository) > 0 && !checkOtherRepositories && meta.SourceRepository != pd.repoInfo.FullName() {
continue
}
candidates = append(candidates, meta)
}
// sort the candidates by similarity
sortV2MetadataByLikenessAndAge(pd.repoInfo, pd.hmacKey, candidates)
digestToMetadata := make(map[digest.Digest]*metadata.V2Metadata)
// an array of unique blob digests ordered from the best mount candidates to worst
layerDigests := []digest.Digest{}
for i := 0; i < len(candidates); i++ {
if len(layerDigests) >= maxExistenceCheckAttempts {
break
}
meta := &candidates[i]
if _, exists := digestToMetadata[meta.Digest]; exists {
// keep reference just to the first mapping (the best mount candidate)
continue
}
if _, exists := pd.checkedDigests[meta.Digest]; exists {
// existence of this digest has already been tested
continue
}
digestToMetadata[meta.Digest] = meta
layerDigests = append(layerDigests, meta.Digest)
}
attempts:
for _, dgst := range layerDigests {
meta := digestToMetadata[dgst]
logrus.Debugf("Checking for presence of layer %s (%s) in %s", diffID, dgst, pd.repoInfo.FullName())
desc, err = pd.repo.Blobs(ctx).Stat(ctx, dgst)
pd.checkedDigests[meta.Digest] = struct{}{}
switch err {
case nil:
if m, ok := digestToMetadata[desc.Digest]; !ok || m.SourceRepository != pd.repoInfo.FullName() || !metadata.CheckV2MetadataHMAC(m, pd.hmacKey) {
// cache mapping from this layer's DiffID to the blobsum
if err := pd.v2MetadataService.TagAndAdd(diffID, pd.hmacKey, metadata.V2Metadata{
Digest: desc.Digest,
SourceRepository: pd.repoInfo.FullName(),
}); err != nil {
return distribution.Descriptor{}, false, xfer.DoNotRetry{Err: err}
}
}
desc.MediaType = schema2.MediaTypeLayer
exists = true
break attempts
case distribution.ErrBlobUnknown:
if meta.SourceRepository == pd.repoInfo.FullName() {
// remove the mapping to the target repository
pd.v2MetadataService.Remove(*meta)
}
default:
logrus.WithError(err).Debugf("Failed to check for presence of layer %s (%s) in %s", diffID, dgst, pd.repoInfo.FullName())
}
}
if exists {
progress.Update(progressOutput, pd.ID(), "Layer already exists")
pd.pushState.Lock()
pd.pushState.remoteLayers[diffID] = desc
pd.pushState.Unlock()
}
return desc, exists, nil
}
// Download is a blocking function which ensures the requested layers are
// present in the layer store. It uses the string returned by the Key method to
// deduplicate downloads. If a given layer is not already known to present in
// the layer store, and the key is not used by an in-progress download, the
// Download method is called to get the layer tar data. Layers are then
// registered in the appropriate order. The caller must call the returned
// release function once it is is done with the returned RootFS object.
func (ldm *LayerDownloadManager) Download(ctx context.Context, initialRootFS image.RootFS, layers []DownloadDescriptor, progressOutput progress.Output) (image.RootFS, func(), error) {
var (
topLayer layer.Layer
topDownload *downloadTransfer
watcher *Watcher
missingLayer bool
transferKey = ""
downloadsByKey = make(map[string]*downloadTransfer)
)
rootFS := initialRootFS
for _, descriptor := range layers {
key := descriptor.Key()
transferKey += key
if !missingLayer {
missingLayer = true
diffID, err := descriptor.DiffID()
if err == nil {
getRootFS := rootFS
getRootFS.Append(diffID)
l, err := ldm.layerStore.Get(getRootFS.ChainID())
if err == nil {
// Layer already exists.
logrus.Debugf("Layer already exists: %s", descriptor.ID())
progress.Update(progressOutput, descriptor.ID(), "Already exists")
if topLayer != nil {
layer.ReleaseAndLog(ldm.layerStore, topLayer)
}
topLayer = l
missingLayer = false
rootFS.Append(diffID)
continue
}
}
}
// Does this layer have the same data as a previous layer in
// the stack? If so, avoid downloading it more than once.
var topDownloadUncasted Transfer
if existingDownload, ok := downloadsByKey[key]; ok {
xferFunc := ldm.makeDownloadFuncFromDownload(descriptor, existingDownload, topDownload)
defer topDownload.Transfer.Release(watcher)
topDownloadUncasted, watcher = ldm.tm.Transfer(transferKey, xferFunc, progressOutput)
topDownload = topDownloadUncasted.(*downloadTransfer)
continue
}
// Layer is not known to exist - download and register it.
progress.Update(progressOutput, descriptor.ID(), "Pulling fs layer")
var xferFunc DoFunc
if topDownload != nil {
xferFunc = ldm.makeDownloadFunc(descriptor, "", topDownload)
defer topDownload.Transfer.Release(watcher)
} else {
xferFunc = ldm.makeDownloadFunc(descriptor, rootFS.ChainID(), nil)
}
topDownloadUncasted, watcher = ldm.tm.Transfer(transferKey, xferFunc, progressOutput)
topDownload = topDownloadUncasted.(*downloadTransfer)
downloadsByKey[key] = topDownload
}
if topDownload == nil {
return rootFS, func() {
if topLayer != nil {
layer.ReleaseAndLog(ldm.layerStore, topLayer)
}
}, nil
}
// Won't be using the list built up so far - will generate it
// from downloaded layers instead.
rootFS.DiffIDs = []layer.DiffID{}
defer func() {
if topLayer != nil {
layer.ReleaseAndLog(ldm.layerStore, topLayer)
}
}()
select {
case <-ctx.Done():
topDownload.Transfer.Release(watcher)
return rootFS, func() {}, ctx.Err()
case <-topDownload.Done():
break
}
l, err := topDownload.result()
if err != nil {
topDownload.Transfer.Release(watcher)
return rootFS, func() {}, err
}
// Must do this exactly len(layers) times, so we don't include the
// base layer on Windows.
for range layers {
if l == nil {
topDownload.Transfer.Release(watcher)
return rootFS, func() {}, errors.New("internal error: too few parent layers")
}
rootFS.DiffIDs = append([]layer.DiffID{l.DiffID()}, rootFS.DiffIDs...)
l = l.Parent()
}
return rootFS, func() { topDownload.Transfer.Release(watcher) }, err
}
func (pd *v2PushDescriptor) Upload(ctx context.Context, progressOutput progress.Output) (digest.Digest, error) {
diffID := pd.DiffID()
logrus.Debugf("Pushing layer: %s", diffID)
// Do we have any blobsums associated with this layer's DiffID?
possibleBlobsums, err := pd.blobSumService.GetBlobSums(diffID)
if err == nil {
dgst, exists, err := blobSumAlreadyExists(ctx, possibleBlobsums, pd.repo, pd.layersPushed)
if err != nil {
progress.Update(progressOutput, pd.ID(), "Image push failed")
return "", retryOnError(err)
}
if exists {
progress.Update(progressOutput, pd.ID(), "Layer already exists")
return dgst, nil
}
}
// if digest was empty or not saved, or if blob does not exist on the remote repository,
// then push the blob.
bs := pd.repo.Blobs(ctx)
// Send the layer
layerUpload, err := bs.Create(ctx)
if err != nil {
return "", retryOnError(err)
}
defer layerUpload.Close()
arch, err := pd.layer.TarStream()
if err != nil {
return "", xfer.DoNotRetry{Err: err}
}
// don't care if this fails; best effort
size, _ := pd.layer.DiffSize()
reader := progress.NewProgressReader(ioutils.NewCancelReadCloser(ctx, arch), progressOutput, size, pd.ID(), "Pushing")
defer reader.Close()
compressedReader := compress(reader)
digester := digest.Canonical.New()
tee := io.TeeReader(compressedReader, digester.Hash())
nn, err := layerUpload.ReadFrom(tee)
compressedReader.Close()
if err != nil {
return "", retryOnError(err)
}
pushDigest := digester.Digest()
if _, err := layerUpload.Commit(ctx, distribution.Descriptor{Digest: pushDigest}); err != nil {
return "", retryOnError(err)
}
// If Commit succeded, that's an indication that the remote registry
// speaks the v2 protocol.
*pd.confirmedV2 = true
logrus.Debugf("uploaded layer %s (%s), %d bytes", diffID, pushDigest, nn)
progress.Update(progressOutput, pd.ID(), "Pushed")
// Cache mapping from this layer's DiffID to the blobsum
if err := pd.blobSumService.Add(diffID, pushDigest); err != nil {
return "", xfer.DoNotRetry{Err: err}
}
pd.layersPushed.Lock()
pd.layersPushed.layersPushed[pushDigest] = true
pd.layersPushed.Unlock()
return pushDigest, nil
}
