Golang Digest.String方法代碼示例

// digestPathComponents provides a consistent path breakdown for a given
// digest. For a generic digest, it will be as follows:
//
// 	<algorithm>/<hex digest>
//
// Most importantly, for tarsum, the layout looks like this:
//
// 	tarsum/<version>/<digest algorithm>/<full digest>
//
// If multilevel is true, the first two bytes of the digest will separate
// groups of digest folder. It will be as follows:
//
// 	<algorithm>/<first two bytes of digest>/<full digest>
//
func digestPathComponents(dgst digest.Digest, multilevel bool) ([]string, error) {
	if err := dgst.Validate(); err != nil {
		return nil, err
	}

	algorithm := blobAlgorithmReplacer.Replace(string(dgst.Algorithm()))
	hex := dgst.Hex()
	prefix := []string{algorithm}

	var suffix []string

	if multilevel {
		suffix = append(suffix, hex[:2])
	}

	suffix = append(suffix, hex)

	if tsi, err := digest.ParseTarSum(dgst.String()); err == nil {
		// We have a tarsum!
		version := tsi.Version
		if version == "" {
			version = "v0"
		}

		prefix = []string{
			"tarsum",
			version,
			tsi.Algorithm,
		}
	}

	return append(prefix, suffix...), nil
}

func (graph *Graph) setLayerDigest(id string, dgst digest.Digest) error {
	root := graph.imageRoot(id)
	if err := ioutil.WriteFile(filepath.Join(root, digestFileName), []byte(dgst.String()), 0600); err != nil {
		return fmt.Errorf("Error storing digest in %s/%s: %s", root, digestFileName, err)
	}
	return nil
}

func (pms proxyManifestStore) Get(dgst digest.Digest) (*manifest.SignedManifest, error) {
	sm, err := pms.localManifests.Get(dgst)
	if err == nil {
		proxyMetrics.ManifestPush(uint64(len(sm.Raw)))
		return sm, err
	}

	sm, err = pms.remoteManifests.Get(dgst)
	if err != nil {
		return nil, err
	}

	proxyMetrics.ManifestPull(uint64(len(sm.Raw)))
	err = pms.localManifests.Put(sm)
	if err != nil {
		return nil, err
	}

	// Schedule the repo for removal
	pms.scheduler.AddManifest(pms.repositoryName, repositoryTTL)

	// Ensure the manifest blob is cleaned up
	pms.scheduler.AddBlob(dgst.String(), repositoryTTL)

	proxyMetrics.ManifestPush(uint64(len(sm.Raw)))

	return sm, err
}

// BuildBlobURL constructs the url for the blob identified by name and dgst.
func (ub *URLBuilder) BuildBlobURL(name string, dgst digest.Digest) (string, error) {
	route := ub.cloneRoute(RouteNameBlob)

	layerURL, err := route.URL("name", name, "digest", dgst.String())
	if err != nil {
		return "", err
	}

	return layerURL.String(), nil
}

func (pbs proxyBlobStore) ServeBlob(ctx context.Context, w http.ResponseWriter, r *http.Request, dgst digest.Digest) error {
	desc, err := pbs.localStore.Stat(ctx, dgst)
	if err != nil && err != distribution.ErrBlobUnknown {
		return err
	}

	if err == nil {
		proxyMetrics.BlobPush(uint64(desc.Size))
		return pbs.localStore.ServeBlob(ctx, w, r, dgst)
	}

	desc, err = pbs.remoteStore.Stat(ctx, dgst)
	if err != nil {
		return err
	}

	remoteReader, err := pbs.remoteStore.Open(ctx, dgst)
	if err != nil {
		return err
	}

	bw, isNew, cleanup, err := getOrCreateBlobWriter(ctx, pbs.localStore, desc)
	if err != nil {
		return err
	}
	defer cleanup()

	if isNew {
		go func() {
			err := streamToStorage(ctx, remoteReader, desc, bw)
			if err != nil {
				context.GetLogger(ctx).Error(err)
			}

			proxyMetrics.BlobPull(uint64(desc.Size))
		}()
		err := streamToClient(ctx, w, desc, bw)
		if err != nil {
			return err
		}

		proxyMetrics.BlobPush(uint64(desc.Size))
		pbs.scheduler.AddBlob(dgst.String(), blobTTL)
		return nil
	}

	err = streamToClient(ctx, w, desc, bw)
	if err != nil {
		return err
	}
	proxyMetrics.BlobPush(uint64(desc.Size))
	return nil
}

func (ms *manifests) Delete(dgst digest.Digest) error {
	u, err := ms.ub.BuildManifestURL(ms.name, dgst.String())
	if err != nil {
		return err
	}
	req, err := http.NewRequest("DELETE", u, nil)
	if err != nil {
		return err
	}

	resp, err := ms.client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if SuccessStatus(resp.StatusCode) {
		return nil
	}
	return handleErrorResponse(resp)
}

func (pms proxyManifestStore) GetByTag(tag string, options ...distribution.ManifestServiceOption) (*manifest.SignedManifest, error) {
	var localDigest digest.Digest

	localManifest, err := pms.localManifests.GetByTag(tag, options...)
	switch err.(type) {
	case distribution.ErrManifestUnknown, distribution.ErrManifestUnknownRevision:
		goto fromremote
	case nil:
		break
	default:
		return nil, err
	}

	localDigest, err = manifestDigest(localManifest)
	if err != nil {
		return nil, err
	}

fromremote:
	var sm *manifest.SignedManifest
	sm, err = pms.remoteManifests.GetByTag(tag, client.AddEtagToTag(tag, localDigest.String()))
	if err != nil {
		return nil, err
	}

	if sm == nil {
		context.GetLogger(pms.ctx).Debugf("Local manifest for %q is latest, dgst=%s", tag, localDigest.String())
		return localManifest, nil
	}
	context.GetLogger(pms.ctx).Debugf("Updated manifest for %q, dgst=%s", tag, localDigest.String())

	err = pms.localManifests.Put(sm)
	if err != nil {
		return nil, err
	}

	dgst, err := manifestDigest(sm)
	if err != nil {
		return nil, err
	}
	pms.scheduler.AddBlob(dgst.String(), repositoryTTL)
	pms.scheduler.AddManifest(pms.repositoryName, repositoryTTL)

	proxyMetrics.ManifestPull(uint64(len(sm.Raw)))
	proxyMetrics.ManifestPush(uint64(len(sm.Raw)))

	return sm, err
}

func setResponseHeaders(w http.ResponseWriter, length int64, mediaType string, digest digest.Digest) {
	w.Header().Set("Content-Length", strconv.FormatInt(length, 10))
	w.Header().Set("Content-Type", mediaType)
	w.Header().Set("Docker-Content-Digest", digest.String())
	w.Header().Set("Etag", digest.String())
}

// loadManifest loads a manifest from a byte array and verifies its content.
// The signature must be verified or an error is returned. If the manifest
// contains no signatures by a trusted key for the name in the manifest, the
// image is not considered verified. The parsed manifest object and a boolean
// for whether the manifest is verified is returned.
func (s *TagStore) loadManifest(eng *engine.Engine, manifestBytes []byte, dgst, ref string) (*registry.ManifestData, bool, error) {
	sig, err := libtrust.ParsePrettySignature(manifestBytes, "signatures")
	if err != nil {
		return nil, false, fmt.Errorf("error parsing payload: %s", err)
	}

	keys, err := sig.Verify()
	if err != nil {
		return nil, false, fmt.Errorf("error verifying payload: %s", err)
	}

	payload, err := sig.Payload()
	if err != nil {
		return nil, false, fmt.Errorf("error retrieving payload: %s", err)
	}

	var manifestDigest digest.Digest

	if dgst != "" {
		manifestDigest, err = digest.ParseDigest(dgst)
		if err != nil {
			return nil, false, fmt.Errorf("invalid manifest digest from registry: %s", err)
		}

		dgstVerifier, err := digest.NewDigestVerifier(manifestDigest)
		if err != nil {
			return nil, false, fmt.Errorf("unable to verify manifest digest from registry: %s", err)
		}

		dgstVerifier.Write(payload)

		if !dgstVerifier.Verified() {
			computedDigest, _ := digest.FromBytes(payload)
			return nil, false, fmt.Errorf("unable to verify manifest digest: registry has %q, computed %q", manifestDigest, computedDigest)
		}
	}

	if utils.DigestReference(ref) && ref != manifestDigest.String() {
		return nil, false, fmt.Errorf("mismatching image manifest digest: got %q, expected %q", manifestDigest, ref)
	}

	var manifest registry.ManifestData
	if err := json.Unmarshal(payload, &manifest); err != nil {
		return nil, false, fmt.Errorf("error unmarshalling manifest: %s", err)
	}
	if manifest.SchemaVersion != 1 {
		return nil, false, fmt.Errorf("unsupported schema version: %d", manifest.SchemaVersion)
	}

	var verified bool
	for _, key := range keys {
		job := eng.Job("trust_key_check")
		b, err := key.MarshalJSON()
		if err != nil {
			return nil, false, fmt.Errorf("error marshalling public key: %s", err)
		}
		namespace := manifest.Name
		if namespace[0] != '/' {
			namespace = "/" + namespace
		}
		stdoutBuffer := bytes.NewBuffer(nil)

		job.Args = append(job.Args, namespace)
		job.Setenv("PublicKey", string(b))
		// Check key has read/write permission (0x03)
		job.SetenvInt("Permission", 0x03)
		job.Stdout.Add(stdoutBuffer)
		if err = job.Run(); err != nil {
			return nil, false, fmt.Errorf("error running key check: %s", err)
		}
		result := engine.Tail(stdoutBuffer, 1)
		log.Debugf("Key check result: %q", result)
		if result == "verified" {
			verified = true
		}
	}

	return &manifest, verified, nil
}

func (ms *manifests) Get(dgst digest.Digest) (*manifest.SignedManifest, error) {
	// Call by Tag endpoint since the API uses the same
	// URL endpoint for tags and digests.
	return ms.GetByTag(dgst.String())
}

func (ms *manifests) Exists(dgst digest.Digest) (bool, error) {
	// Call by Tag endpoint since the API uses the same
	// URL endpoint for tags and digests.
	return ms.ExistsByTag(dgst.String())
}

func (rsrbds *repositoryScopedRedisBlobDescriptorService) blobDescriptorHashKey(dgst digest.Digest) string {
	return "repository::" + rsrbds.repo + "::blobs::" + dgst.String()
}