Golang Layer.DiffID方法代碼示例

func (p *v2Pusher) pushLayerIfNecessary(out io.Writer, l layer.Layer) (digest.Digest, error) {
	logrus.Debugf("Pushing layer: %s", l.DiffID())

	// Do we have any blobsums associated with this layer's DiffID?
	possibleBlobsums, err := p.blobSumService.GetBlobSums(l.DiffID())
	if err == nil {
		dgst, exists, err := p.blobSumAlreadyExists(possibleBlobsums)
		if err != nil {
			out.Write(p.sf.FormatProgress(stringid.TruncateID(string(l.DiffID())), "Image push failed", nil))
			return "", err
		}
		if exists {
			out.Write(p.sf.FormatProgress(stringid.TruncateID(string(l.DiffID())), "Layer already exists", nil))
			return dgst, nil
		}
	}

	// if digest was empty or not saved, or if blob does not exist on the remote repository,
	// then push the blob.
	pushDigest, err := p.pushV2Layer(p.repo.Blobs(context.Background()), l)
	if err != nil {
		return "", err
	}
	// Cache mapping from this layer's DiffID to the blobsum
	if err := p.blobSumService.Add(l.DiffID(), pushDigest); err != nil {
		return "", err
	}

	return pushDigest, nil
}

func (p *v2Pusher) pushV2Layer(bs distribution.BlobService, l layer.Layer) (digest.Digest, error) {
	out := p.config.OutStream
	displayID := stringid.TruncateID(string(l.DiffID()))

	out.Write(p.sf.FormatProgress(displayID, "Preparing", nil))

	arch, err := l.TarStream()
	if err != nil {
		return "", err
	}

	// Send the layer
	layerUpload, err := bs.Create(context.Background())
	if err != nil {
		return "", err
	}
	defer layerUpload.Close()

	// don't care if this fails; best effort
	size, _ := l.DiffSize()

	reader := progressreader.New(progressreader.Config{
		In:        ioutil.NopCloser(arch), // we'll take care of close here.
		Out:       out,
		Formatter: p.sf,
		Size:      size,
		NewLines:  false,
		ID:        displayID,
		Action:    "Pushing",
	})

	compressedReader := compress(reader)

	digester := digest.Canonical.New()
	tee := io.TeeReader(compressedReader, digester.Hash())

	out.Write(p.sf.FormatProgress(displayID, "Pushing", nil))
	nn, err := layerUpload.ReadFrom(tee)
	compressedReader.Close()
	if err != nil {
		return "", err
	}

	dgst := digester.Digest()
	if _, err := layerUpload.Commit(context.Background(), distribution.Descriptor{Digest: dgst}); err != nil {
		return "", err
	}

	logrus.Debugf("uploaded layer %s (%s), %d bytes", l.DiffID(), dgst, nn)
	out.Write(p.sf.FormatProgress(displayID, "Pushed", nil))

	return dgst, nil
}

func (p *v2Pusher) pushV2Tag(association tag.Association) error {
	ref := association.Ref
	logrus.Debugf("Pushing repository: %s", ref.String())

	img, err := p.config.ImageStore.Get(association.ImageID)
	if err != nil {
		return fmt.Errorf("could not find image from tag %s: %v", ref.String(), err)
	}

	out := p.config.OutStream

	var l layer.Layer

	topLayerID := img.RootFS.ChainID()
	if topLayerID == "" {
		l = layer.EmptyLayer
	} else {
		l, err = p.config.LayerStore.Get(topLayerID)
		if err != nil {
			return fmt.Errorf("failed to get top layer from image: %v", err)
		}
		defer layer.ReleaseAndLog(p.config.LayerStore, l)
	}

	fsLayers := make(map[layer.DiffID]schema1.FSLayer)

	// Push empty layer if necessary
	for _, h := range img.History {
		if h.EmptyLayer {
			dgst, err := p.pushLayerIfNecessary(out, layer.EmptyLayer)
			if err != nil {
				return err
			}
			p.layersPushed[dgst] = true
			fsLayers[layer.EmptyLayer.DiffID()] = schema1.FSLayer{BlobSum: dgst}
			break
		}
	}

	for i := 0; i < len(img.RootFS.DiffIDs); i++ {
		dgst, err := p.pushLayerIfNecessary(out, l)
		if err != nil {
			return err
		}

		p.layersPushed[dgst] = true
		fsLayers[l.DiffID()] = schema1.FSLayer{BlobSum: dgst}

		l = l.Parent()
	}

	var tag string
	if tagged, isTagged := ref.(reference.Tagged); isTagged {
		tag = tagged.Tag()
	}
	m, err := CreateV2Manifest(p.repo.Name(), tag, img, fsLayers)
	if err != nil {
		return err
	}

	logrus.Infof("Signed manifest for %s using daemon's key: %s", ref.String(), p.config.TrustKey.KeyID())
	signed, err := schema1.Sign(m, p.config.TrustKey)
	if err != nil {
		return err
	}

	manifestDigest, manifestSize, err := digestFromManifest(signed, p.repo.Name())
	if err != nil {
		return err
	}
	if manifestDigest != "" {
		if tagged, isTagged := ref.(reference.Tagged); isTagged {
			// NOTE: do not change this format without first changing the trust client
			// code. This information is used to determine what was pushed and should be signed.
			out.Write(p.sf.FormatStatus("", "%s: digest: %s size: %d", tagged.Tag(), manifestDigest, manifestSize))
		}
	}

	manSvc, err := p.repo.Manifests(context.Background())
	if err != nil {
		return err
	}
	return manSvc.Put(signed)
}