package graph
import (
"errors"
"fmt"
"io"
"net"
"net/url"
"strings"
"time"
"github.com/Sirupsen/logrus"
"github.com/docker/distribution/registry/client/transport"
"github.com/docker/docker/image"
"github.com/docker/docker/pkg/progressreader"
"github.com/docker/docker/pkg/streamformatter"
"github.com/docker/docker/pkg/stringid"
"github.com/docker/docker/registry"
"github.com/docker/docker/utils"
)
type v1Puller struct {
*TagStore
endpoint registry.APIEndpoint
config *ImagePullConfig
sf *streamformatter.StreamFormatter
repoInfo *registry.RepositoryInfo
session *registry.Session
}
func (p *v1Puller) Pull(tag string) (fallback bool, err error) {
if utils.DigestReference(tag) {
// Allowing fallback, because HTTPS v1 is before HTTP v2
return true, registry.ErrNoSupport{errors.New("Cannot pull by digest with v1 registry")}
}
tlsConfig, err := p.registryService.TLSConfig(p.repoInfo.Index.Name)
if err != nil {
return false, err
}
// Adds Docker-specific headers as well as user-specified headers (metaHeaders)
tr := transport.NewTransport(
// TODO(tiborvass): was ReceiveTimeout
registry.NewTransport(tlsConfig),
registry.DockerHeaders(p.config.MetaHeaders)...,
)
client := registry.HTTPClient(tr)
v1Endpoint, err := p.endpoint.ToV1Endpoint(p.config.MetaHeaders)
if err != nil {
logrus.Debugf("Could not get v1 endpoint: %v", err)
return true, err
}
p.session, err = registry.NewSession(client, p.config.AuthConfig, v1Endpoint)
if err != nil {
// TODO(dmcgowan): Check if should fallback
logrus.Debugf("Fallback from error: %s", err)
return true, err
}
if err := p.pullRepository(tag); err != nil {
// TODO(dmcgowan): Check if should fallback
return false, err
}
out := p.config.OutStream
out.Write(p.sf.FormatStatus("", "%s: this image was pulled from a legacy registry. Important: This registry version will not be supported in future versions of docker.", p.repoInfo.CanonicalName))
return false, 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
}
func (p *v1Puller) pullImage(out io.Writer, imgID, endpoint string) (layersDownloaded bool, err error) {
var history []string
history, err = p.session.GetRemoteHistory(imgID, endpoint)
if err != nil {
return false, err
}
out.Write(p.sf.FormatProgress(stringid.TruncateID(imgID), "Pulling dependent layers", nil))
// FIXME: Try to stream the images?
// FIXME: Launch the getRemoteImage() in goroutines
sessionID := p.session.ID()
// As imgID has been retained in pullRepository, no need to retain again
p.graph.Retain(sessionID, history[1:]...)
defer p.graph.Release(sessionID, history[1:]...)
layersDownloaded = false
for i := len(history) - 1; i >= 0; i-- {
id := history[i]
// ensure no two downloads of the same layer happen at the same time
poolKey := "layer:" + id
broadcaster, found := p.poolAdd("pull", poolKey)
broadcaster.Add(out)
if found {
logrus.Debugf("Image (id: %s) pull is already running, skipping", id)
err = broadcaster.Wait()
if err != nil {
return layersDownloaded, err
}
continue
}
// This must use a closure so it captures the value of err when
// the function returns, not when the 'defer' is evaluated.
defer func() {
p.poolRemoveWithError("pull", poolKey, err)
}()
if !p.graph.Exists(id) {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Pulling metadata", nil))
var (
imgJSON []byte
imgSize int64
err error
img *image.Image
)
retries := 5
for j := 1; j <= retries; j++ {
imgJSON, imgSize, err = p.session.GetRemoteImageJSON(id, endpoint)
if err != nil && j == retries {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Error pulling dependent layers", nil))
return layersDownloaded, err
} else if err != nil {
time.Sleep(time.Duration(j) * 500 * time.Millisecond)
continue
}
img, err = image.NewImgJSON(imgJSON)
layersDownloaded = true
if err != nil && j == retries {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Error pulling dependent layers", nil))
return layersDownloaded, fmt.Errorf("Failed to parse json: %s", err)
} else if err != nil {
time.Sleep(time.Duration(j) * 500 * time.Millisecond)
continue
} else {
break
}
}
for j := 1; j <= retries; j++ {
// Get the layer
status := "Pulling fs layer"
if j > 1 {
status = fmt.Sprintf("Pulling fs layer [retries: %d]", j)
}
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), status, nil))
layer, err := p.session.GetRemoteImageLayer(img.ID, endpoint, imgSize)
if uerr, ok := err.(*url.Error); ok {
err = uerr.Err
}
if terr, ok := err.(net.Error); ok && terr.Timeout() && j < retries {
time.Sleep(time.Duration(j) * 500 * time.Millisecond)
continue
} else if err != nil {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Error pulling dependent layers", nil))
return layersDownloaded, err
}
layersDownloaded = true
defer layer.Close()
err = p.graph.Register(v1Descriptor{img},
progressreader.New(progressreader.Config{
In: layer,
Out: broadcaster,
Formatter: p.sf,
Size: imgSize,
NewLines: false,
ID: stringid.TruncateID(id),
Action: "Downloading",
}))
if terr, ok := err.(net.Error); ok && terr.Timeout() && j < retries {
time.Sleep(time.Duration(j) * 500 * time.Millisecond)
continue
} else if err != nil {
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Error downloading dependent layers", nil))
return layersDownloaded, err
} else {
break
}
}
}
broadcaster.Write(p.sf.FormatProgress(stringid.TruncateID(id), "Download complete", nil))
broadcaster.Close()
}
return layersDownloaded, nil
}