Exemplo n.º 1
0
Arquivo: pull.go Projeto: devick/flynn
func (s *TagStore) pullV2Tag(eng *engine.Engine, r *registry.Session, out io.Writer, endpoint *registry.Endpoint, repoInfo *registry.RepositoryInfo, tag string, sf *utils.StreamFormatter, parallel bool, auth *registry.RequestAuthorization) (bool, error) {
	log.Debugf("Pulling tag from V2 registry: %q", tag)

	manifestBytes, manifestDigest, err := r.GetV2ImageManifest(endpoint, repoInfo.RemoteName, tag, auth)
	if err != nil {
		return false, err
	}

	// loadManifest ensures that the manifest payload has the expected digest
	// if the tag is a digest reference.
	manifest, verified, err := s.loadManifest(eng, manifestBytes, manifestDigest, tag)
	if err != nil {
		return false, fmt.Errorf("error verifying manifest: %s", err)
	}

	if err := checkValidManifest(manifest); err != nil {
		return false, err
	}

	if verified {
		log.Printf("Image manifest for %s has been verified", utils.ImageReference(repoInfo.CanonicalName, tag))
	}
	out.Write(sf.FormatStatus(tag, "Pulling from %s", repoInfo.CanonicalName))

	downloads := make([]downloadInfo, len(manifest.FSLayers))

	for i := len(manifest.FSLayers) - 1; i >= 0; i-- {
		var (
			sumStr  = manifest.FSLayers[i].BlobSum
			imgJSON = []byte(manifest.History[i].V1Compatibility)
		)

		img, err := image.NewImgJSON(imgJSON)
		if err != nil {
			return false, fmt.Errorf("failed to parse json: %s", err)
		}
		downloads[i].img = img

		// Check if exists
		if s.graph.Exists(img.ID) {
			log.Debugf("Image already exists: %s", img.ID)
			continue
		}

		dgst, err := digest.ParseDigest(sumStr)
		if err != nil {
			return false, err
		}
		downloads[i].digest = dgst

		out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Pulling fs layer", nil))

		downloadFunc := func(di *downloadInfo) error {
			log.Debugf("pulling blob %q to V1 img %s", sumStr, img.ID)

			if c, err := s.poolAdd("pull", "img:"+img.ID); err != nil {
				if c != nil {
					out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Layer already being pulled by another client. Waiting.", nil))
					<-c
					out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Download complete", nil))
				} else {
					log.Debugf("Image (id: %s) pull is already running, skipping: %v", img.ID, err)
				}
			} else {
				defer s.poolRemove("pull", "img:"+img.ID)
				tmpFile, err := ioutil.TempFile("", "GetV2ImageBlob")
				if err != nil {
					return err
				}

				r, l, err := r.GetV2ImageBlobReader(endpoint, repoInfo.RemoteName, di.digest.Algorithm(), di.digest.Hex(), auth)
				if err != nil {
					return err
				}
				defer r.Close()

				verifier, err := digest.NewDigestVerifier(di.digest)
				if err != nil {
					return err
				}

				if _, err := io.Copy(tmpFile, progressreader.New(progressreader.Config{
					In:        ioutil.NopCloser(io.TeeReader(r, verifier)),
					Out:       out,
					Formatter: sf,
					Size:      int(l),
					NewLines:  false,
					ID:        stringid.TruncateID(img.ID),
					Action:    "Downloading",
				})); err != nil {
					return fmt.Errorf("unable to copy v2 image blob data: %s", err)
				}

				out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Verifying Checksum", nil))

				if !verifier.Verified() {
					log.Infof("Image verification failed: checksum mismatch for %q", di.digest.String())
					verified = false
				}

				out.Write(sf.FormatProgress(stringid.TruncateID(img.ID), "Download complete", nil))

				log.Debugf("Downloaded %s to tempfile %s", img.ID, tmpFile.Name())
				di.tmpFile = tmpFile
				di.length = l
				di.downloaded = true
			}
			di.imgJSON = imgJSON

			return nil
		}

		if parallel {
			downloads[i].err = make(chan error)
			go func(di *downloadInfo) {
				di.err <- downloadFunc(di)
			}(&downloads[i])
		} else {
			err := downloadFunc(&downloads[i])
			if err != nil {
				return false, err
			}
		}
	}

	var tagUpdated bool
	for i := len(downloads) - 1; i >= 0; i-- {
		d := &downloads[i]
		if d.err != nil {
			err := <-d.err
			if err != nil {
				return false, err
			}
		}
		if d.downloaded {
			// if tmpFile is empty assume download and extracted elsewhere
			defer os.Remove(d.tmpFile.Name())
			defer d.tmpFile.Close()
			d.tmpFile.Seek(0, 0)
			if d.tmpFile != nil {
				err = s.graph.Register(d.img,
					progressreader.New(progressreader.Config{
						In:        d.tmpFile,
						Out:       out,
						Formatter: sf,
						Size:      int(d.length),
						ID:        stringid.TruncateID(d.img.ID),
						Action:    "Extracting",
					}))
				if err != nil {
					return false, err
				}

				// FIXME: Pool release here for parallel tag pull (ensures any downloads block until fully extracted)
			}
			out.Write(sf.FormatProgress(stringid.TruncateID(d.img.ID), "Pull complete", nil))
			tagUpdated = true
		} else {
			out.Write(sf.FormatProgress(stringid.TruncateID(d.img.ID), "Already exists", nil))
		}

	}

	// Check for new tag if no layers downloaded
	if !tagUpdated {
		repo, err := s.Get(repoInfo.LocalName)
		if err != nil {
			return false, err
		}
		if repo != nil {
			if _, exists := repo[tag]; !exists {
				tagUpdated = true
			}
		}
	}

	if verified && tagUpdated {
		out.Write(sf.FormatStatus(utils.ImageReference(repoInfo.CanonicalName, tag), "The image you are pulling has been verified. Important: image verification is a tech preview feature and should not be relied on to provide security."))
	}

	if manifestDigest != "" {
		out.Write(sf.FormatStatus("", "Digest: %s", manifestDigest))
	}

	if utils.DigestReference(tag) {
		if err = s.SetDigest(repoInfo.LocalName, tag, downloads[0].img.ID); err != nil {
			return false, err
		}
	} else {
		// only set the repository/tag -> image ID mapping when pulling by tag (i.e. not by digest)
		if err = s.Set(repoInfo.LocalName, tag, downloads[0].img.ID, true); err != nil {
			return false, err
		}
	}

	return tagUpdated, nil
}
Exemplo n.º 2
0
func (s *TagStore) pullV2Tag(eng *engine.Engine, r *registry.Session, out io.Writer, localName, remoteName, tag string, sf *utils.StreamFormatter, parallel bool) (bool, error) {
	log.Debugf("Pulling tag from V2 registry: %q", tag)
	manifestBytes, err := r.GetV2ImageManifest(remoteName, tag, nil)
	if err != nil {
		return false, err
	}

	manifest, verified, err := s.verifyManifest(eng, manifestBytes)
	if err != nil {
		return false, fmt.Errorf("error verifying manifest: %s", err)
	}

	if len(manifest.FSLayers) != len(manifest.History) {
		return false, fmt.Errorf("length of history not equal to number of layers")
	}

	if verified {
		out.Write(sf.FormatStatus(localName+":"+tag, "The image you are pulling has been verified"))
	} else {
		out.Write(sf.FormatStatus(tag, "Pulling from %s", localName))
	}

	if len(manifest.FSLayers) == 0 {
		return false, fmt.Errorf("no blobSums in manifest")
	}

	downloads := make([]downloadInfo, len(manifest.FSLayers))

	for i := len(manifest.FSLayers) - 1; i >= 0; i-- {
		var (
			sumStr  = manifest.FSLayers[i].BlobSum
			imgJSON = []byte(manifest.History[i].V1Compatibility)
		)

		img, err := image.NewImgJSON(imgJSON)
		if err != nil {
			return false, fmt.Errorf("failed to parse json: %s", err)
		}
		downloads[i].img = img

		// Check if exists
		if s.graph.Exists(img.ID) {
			log.Debugf("Image already exists: %s", img.ID)
			continue
		}

		chunks := strings.SplitN(sumStr, ":", 2)
		if len(chunks) < 2 {
			return false, fmt.Errorf("expected 2 parts in the sumStr, got %#v", chunks)
		}
		sumType, checksum := chunks[0], chunks[1]
		out.Write(sf.FormatProgress(utils.TruncateID(img.ID), "Pulling fs layer", nil))

		downloadFunc := func(di *downloadInfo) error {
			log.Debugf("pulling blob %q to V1 img %s", sumStr, img.ID)

			if c, err := s.poolAdd("pull", "img:"+img.ID); err != nil {
				if c != nil {
					out.Write(sf.FormatProgress(utils.TruncateID(img.ID), "Layer already being pulled by another client. Waiting.", nil))
					<-c
					out.Write(sf.FormatProgress(utils.TruncateID(img.ID), "Download complete", nil))
				} else {
					log.Debugf("Image (id: %s) pull is already running, skipping: %v", img.ID, err)
				}
			} else {
				defer s.poolRemove("pull", "img:"+img.ID)
				tmpFile, err := ioutil.TempFile("", "GetV2ImageBlob")
				if err != nil {
					return err
				}

				r, l, err := r.GetV2ImageBlobReader(remoteName, sumType, checksum, nil)
				if err != nil {
					return err
				}
				defer r.Close()
				io.Copy(tmpFile, utils.ProgressReader(r, int(l), out, sf, false, utils.TruncateID(img.ID), "Downloading"))

				out.Write(sf.FormatProgress(utils.TruncateID(img.ID), "Download complete", nil))

				log.Debugf("Downloaded %s to tempfile %s", img.ID, tmpFile.Name())
				di.tmpFile = tmpFile
				di.length = l
				di.downloaded = true
			}
			di.imgJSON = imgJSON

			return nil
		}

		if parallel {
			downloads[i].err = make(chan error)
			go func(di *downloadInfo) {
				di.err <- downloadFunc(di)
			}(&downloads[i])
		} else {
			err := downloadFunc(&downloads[i])
			if err != nil {
				return false, err
			}
		}
	}

	var layersDownloaded bool
	for i := len(downloads) - 1; i >= 0; i-- {
		d := &downloads[i]
		if d.err != nil {
			err := <-d.err
			if err != nil {
				return false, err
			}
		}
		if d.downloaded {
			// if tmpFile is empty assume download and extracted elsewhere
			defer os.Remove(d.tmpFile.Name())
			defer d.tmpFile.Close()
			d.tmpFile.Seek(0, 0)
			if d.tmpFile != nil {
				err = s.graph.Register(d.img,
					utils.ProgressReader(d.tmpFile, int(d.length), out, sf, false, utils.TruncateID(d.img.ID), "Extracting"))
				if err != nil {
					return false, err
				}

				// FIXME: Pool release here for parallel tag pull (ensures any downloads block until fully extracted)
			}
			out.Write(sf.FormatProgress(utils.TruncateID(d.img.ID), "Pull complete", nil))
			layersDownloaded = true
		} else {
			out.Write(sf.FormatProgress(utils.TruncateID(d.img.ID), "Already exists", nil))
		}

	}

	if err = s.Set(localName, tag, downloads[0].img.ID, true); err != nil {
		return false, err
	}

	return layersDownloaded, nil
}