// loadImage fetches the image with the given id from the graph.
func (graph *Graph) loadImage(id string) (*image.Image, error) {
root := graph.imageRoot(id)
// Open the JSON file to decode by streaming
jsonSource, err := os.Open(jsonPath(root))
if err != nil {
return nil, err
}
defer jsonSource.Close()
img := &image.Image{}
dec := json.NewDecoder(jsonSource)
// Decode the JSON data
if err := dec.Decode(img); err != nil {
return nil, err
}
if img.ID == "" {
img.ID = id
}
if img.Parent == "" && img.ParentID != "" && img.ParentID.Validate() == nil {
img.Parent = img.ParentID.Hex()
}
// compatibilityID for parent
parent, err := ioutil.ReadFile(filepath.Join(root, parentFileName))
if err == nil && len(parent) > 0 {
img.Parent = string(parent)
}
if err := image.ValidateID(img.ID); err != nil {
return nil, err
}
if buf, err := ioutil.ReadFile(filepath.Join(root, layersizeFileName)); err != nil {
if !os.IsNotExist(err) {
return nil, err
}
// If the layersize file does not exist then set the size to a negative number
// because a layer size of 0 (zero) is valid
img.Size = -1
} else {
// Using Atoi here instead would temporarily convert the size to a machine
// dependent integer type, which causes images larger than 2^31 bytes to
// display negative sizes on 32-bit machines:
size, err := strconv.ParseInt(string(buf), 10, 64)
if err != nil {
return nil, err
}
img.Size = int64(size)
}
return img, nil
}
func validateRemoteName(remoteName string) error {
if !strings.Contains(remoteName, "/") {
// the repository name must not be a valid image ID
if err := image.ValidateID(remoteName); err == nil {
return fmt.Errorf("Invalid repository name (%s), cannot specify 64-byte hexadecimal strings", remoteName)
}
}
return v2.ValidateRepositoryName(remoteName)
}
func (s *TagStore) recursiveLoad(address, tmpImageDir string) error {
if _, err := s.LookupImage(address); err != nil {
logrus.Debugf("Loading %s", address)
imageJSON, err := ioutil.ReadFile(filepath.Join(tmpImageDir, "repo", address, "json"))
if err != nil {
logrus.Debugf("Error reading json: %v", err)
return err
}
layer, err := os.Open(filepath.Join(tmpImageDir, "repo", address, "layer.tar"))
if err != nil {
logrus.Debugf("Error reading embedded tar: %v", err)
return err
}
img, err := image.NewImgJSON(imageJSON)
if err != nil {
logrus.Debugf("Error unmarshalling json: %v", err)
return err
}
if err := image.ValidateID(img.ID); err != nil {
logrus.Debugf("Error validating ID: %v", err)
return err
}
// ensure no two downloads of the same layer happen at the same time
poolKey := "layer:" + img.ID
broadcaster, found := s.poolAdd("pull", poolKey)
if found {
logrus.Debugf("Image (id: %s) load is already running, waiting", img.ID)
return broadcaster.Wait()
}
defer s.poolRemove("pull", poolKey)
if img.Parent != "" {
if !s.graph.Exists(img.Parent) {
if err := s.recursiveLoad(img.Parent, tmpImageDir); err != nil {
return err
}
}
}
if err := s.graph.Register(v1Descriptor{img}, layer); err != nil {
return err
}
}
logrus.Debugf("Completed processing %s", address)
return nil
}
// Register imports a pre-existing image into the graph.
// Returns nil if the image is already registered.
func (graph *Graph) Register(im image.Descriptor, layerData io.Reader) (err error) {
imgID := im.ID()
if err := image.ValidateID(imgID); err != nil {
return err
}
// this is needed cause pull_v2 attemptIDReuse could deadlock
graph.imagesMutex.Lock()
defer graph.imagesMutex.Unlock()
// We need this entire operation to be atomic within the engine. Note that
// this doesn't mean Register is fully safe yet.
graph.imageMutex.Lock(imgID)
defer graph.imageMutex.Unlock(imgID)
return graph.register(im, layerData)
}
// fixManifestLayers removes repeated layers from the manifest and checks the
// correctness of the parent chain.
func fixManifestLayers(m *manifest.Manifest) error {
images := make([]*image.Image, len(m.FSLayers))
for i := range m.FSLayers {
img, err := image.NewImgJSON([]byte(m.History[i].V1Compatibility))
if err != nil {
return err
}
images[i] = img
if err := image.ValidateID(img.ID); err != nil {
return err
}
}
if images[len(images)-1].Parent != "" {
return errors.New("Invalid parent ID in the base layer of the image.")
}
// check general duplicates to error instead of a deadlock
idmap := make(map[string]struct{})
var lastID string
for _, img := range images {
// skip IDs that appear after each other, we handle those later
if _, exists := idmap[img.ID]; img.ID != lastID && exists {
return fmt.Errorf("ID %+v appears multiple times in manifest", img.ID)
}
lastID = img.ID
idmap[lastID] = struct{}{}
}
// backwards loop so that we keep the remaining indexes after removing items
for i := len(images) - 2; i >= 0; i-- {
if images[i].ID == images[i+1].ID { // repeated ID. remove and continue
m.FSLayers = append(m.FSLayers[:i], m.FSLayers[i+1:]...)
m.History = append(m.History[:i], m.History[i+1:]...)
} else if images[i].Parent != images[i+1].ID {
return fmt.Errorf("Invalid parent ID. Expected %v, got %v.", images[i+1].ID, images[i].Parent)
}
}
return nil
}
func (p *v1Puller) pullRepository(askedTag string) error {
out := p.config.OutStream
out.Write(p.sf.FormatStatus("", "Pulling repository %s", p.repoInfo.CanonicalName))
repoData, err := p.session.GetRepositoryData(p.repoInfo.RemoteName)
if err != nil {
if strings.Contains(err.Error(), "HTTP code: 404") {
return fmt.Errorf("Error: image %s not found", utils.ImageReference(p.repoInfo.RemoteName, askedTag))
}
// Unexpected HTTP error
return err
}
logrus.Debugf("Retrieving the tag list")
tagsList := make(map[string]string)
if askedTag == "" {
tagsList, err = p.session.GetRemoteTags(repoData.Endpoints, p.repoInfo.RemoteName)
} else {
var tagID string
tagID, err = p.session.GetRemoteTag(repoData.Endpoints, p.repoInfo.RemoteName, askedTag)
tagsList[askedTag] = tagID
}
if err != nil {
if err == registry.ErrRepoNotFound && askedTag != "" {
return fmt.Errorf("Tag %s not found in repository %s", askedTag, p.repoInfo.CanonicalName)
}
logrus.Errorf("unable to get remote tags: %s", err)
return err
}
for tag, id := range tagsList {
repoData.ImgList[id] = ®istry.ImgData{
ID: id,
Tag: tag,
Checksum: "",
}
}
logrus.Debugf("Registering tags")
// If no tag has been specified, pull them all
if askedTag == "" {
for tag, id := range tagsList {
repoData.ImgList[id].Tag = tag
}
} else {
// Otherwise, check that the tag exists and use only that one
id, exists := tagsList[askedTag]
if !exists {
return fmt.Errorf("Tag %s not found in repository %s", askedTag, p.repoInfo.CanonicalName)
}
repoData.ImgList[id].Tag = askedTag
}
errors := make(chan error)
layersDownloaded := false
imgIDs := []string{}
sessionID := p.session.ID()
defer func() {
p.graph.Release(sessionID, imgIDs...)
}()
for _, imgData := range repoData.ImgList {
downloadImage := func(img *registry.ImgData) {
if askedTag != "" && img.Tag != askedTag {
errors <- nil
return
}
if img.Tag == "" {
logrus.Debugf("Image (id: %s) present in this repository but untagged, skipping", img.ID)
errors <- nil
return
}
if err := image.ValidateID(img.ID); err != nil {
errors <- err
return
}
// ensure no two downloads of the same image happen at the same time
poolKey := "img:" + img.ID
broadcaster, found := p.poolAdd("pull", poolKey)
broadcaster.Add(out)
if found {
errors <- broadcaster.Wait()
return
}
defer p.poolRemove("pull", poolKey)
// we need to retain it until tagging
p.graph.Retain(sessionID, img.ID)
imgIDs = append(imgIDs, img.ID)
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), fmt.Sprintf("Pulling image (%s) from %s", img.Tag, p.repoInfo.CanonicalName), nil))
success := false
var lastErr, err error
var isDownloaded bool
for _, ep := range p.repoInfo.Index.Mirrors {
ep += "v1/"
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), fmt.Sprintf("Pulling image (%s) from %s, mirror: %s", img.Tag, p.repoInfo.CanonicalName, ep), nil))
if isDownloaded, err = p.pullImage(broadcaster, img.ID, ep); 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, ep, err)
continue
}
layersDownloaded = layersDownloaded || isDownloaded
success = true
break
}
if !success {
for _, ep := range repoData.Endpoints {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), fmt.Sprintf("Pulling image (%s) from %s, endpoint: %s", img.Tag, p.repoInfo.CanonicalName, ep), nil))
if isDownloaded, err = p.pullImage(broadcaster, img.ID, ep); 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
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), fmt.Sprintf("Error pulling image (%s) from %s, endpoint: %s, %s", img.Tag, p.repoInfo.CanonicalName, ep, err), nil))
continue
}
layersDownloaded = layersDownloaded || isDownloaded
success = true
break
}
}
if !success {
err := fmt.Errorf("Error pulling image (%s) from %s, %v", img.Tag, p.repoInfo.CanonicalName, lastErr)
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), err.Error(), nil))
errors <- err
broadcaster.CloseWithError(err)
return
}
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(img.ID), "Download complete", nil))
errors <- nil
}
go downloadImage(imgData)
}
var lastError error
for i := 0; i < len(repoData.ImgList); i++ {
if err := <-errors; err != nil {
lastError = err
}
}
if lastError != nil {
return lastError
}
for tag, id := range tagsList {
if askedTag != "" && tag != askedTag {
continue
}
if err := p.Tag(p.repoInfo.LocalName, tag, id, true); err != nil {
return err
}
}
requestedTag := p.repoInfo.LocalName
if len(askedTag) > 0 {
requestedTag = utils.ImageReference(p.repoInfo.LocalName, askedTag)
}
writeStatus(requestedTag, out, p.sf, layersDownloaded)
return nil
}
