func createRepository(env *testEnv, t *testing.T, imageName string, tag string) {
	unsignedManifest := &manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: imageName,
		Tag:  tag,
		FSLayers: []manifest.FSLayer{
			{
				BlobSum: "asdf",
			},
			{
				BlobSum: "qwer",
			},
		},
	}

	// Push 2 random layers
	expectedLayers := make(map[digest.Digest]io.ReadSeeker)

	for i := range unsignedManifest.FSLayers {
		rs, dgstStr, err := testutil.CreateRandomTarFile()

		if err != nil {
			t.Fatalf("error creating random layer %d: %v", i, err)
		}
		dgst := digest.Digest(dgstStr)

		expectedLayers[dgst] = rs
		unsignedManifest.FSLayers[i].BlobSum = dgst

		uploadURLBase, _ := startPushLayer(t, env.builder, imageName)
		pushLayer(t, env.builder, imageName, dgst, uploadURLBase, rs)
	}

	signedManifest, err := manifest.Sign(unsignedManifest, env.pk)
	if err != nil {
		t.Fatalf("unexpected error signing manifest: %v", err)
	}

	payload, err := signedManifest.Payload()
	checkErr(t, err, "getting manifest payload")

	dgst, err := digest.FromBytes(payload)
	checkErr(t, err, "digesting manifest")

	manifestDigestURL, err := env.builder.BuildManifestURL(imageName, dgst.String())
	checkErr(t, err, "building manifest url")

	resp := putManifest(t, "putting signed manifest", manifestDigestURL, signedManifest)
	checkResponse(t, "putting signed manifest", resp, http.StatusAccepted)
	checkHeaders(t, resp, http.Header{
		"Location":              []string{manifestDigestURL},
		"Docker-Content-Digest": []string{dgst.String()},
	})
}

func populateRepo(t *testing.T, ctx context.Context, repository distribution.Repository, name, tag string) (digest.Digest, error) {
	m := manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: name,
		Tag:  tag,
	}

	for i := 0; i < 2; i++ {
		wr, err := repository.Blobs(ctx).Create(ctx)
		if err != nil {
			t.Fatalf("unexpected error creating test upload: %v", err)
		}

		rs, ts, err := testutil.CreateRandomTarFile()
		if err != nil {
			t.Fatalf("unexpected error generating test layer file")
		}
		dgst := digest.Digest(ts)
		if _, err := io.Copy(wr, rs); err != nil {
			t.Fatalf("unexpected error copying to upload: %v", err)
		}

		if _, err := wr.Commit(ctx, distribution.Descriptor{Digest: dgst}); err != nil {
			t.Fatalf("unexpected error finishing upload: %v", err)
		}
	}

	pk, err := libtrust.GenerateECP256PrivateKey()
	if err != nil {
		t.Fatalf("unexpected error generating private key: %v", err)
	}

	sm, err := manifest.Sign(&m, pk)
	if err != nil {
		t.Fatalf("error signing manifest: %v", err)
	}

	ms, err := repository.Manifests(ctx)
	if err != nil {
		t.Fatalf(err.Error())
	}
	ms.Put(sm)
	if err != nil {
		t.Fatalf("unexpected errors putting manifest: %v", err)
	}
	pl, err := sm.Payload()
	if err != nil {
		t.Fatal(err)
	}
	return digest.FromBytes(pl)
}

func signAndServeManifest(rw http.ResponseWriter, code int, header http.Header, m *manifest.Manifest) {
	newSm, err := manifest.Sign(m, key)
	if err != nil {
		http.Error(rw, err.Error(), http.StatusInternalServerError)
		return
	}

	if header.Get("Docker-Content-Digest") != "" {
		payload, err := newSm.Payload()
		if err != nil {
			http.Error(rw, err.Error(), http.StatusInternalServerError)
			return
		}
		dgst, err := digest.FromBytes(payload)
		if err != nil {
			http.Error(rw, err.Error(), http.StatusInternalServerError)
			return
		}

		header.Set("Docker-Content-Digest", dgst.String())
	}

	copied, err := json.MarshalIndent(newSm, "", "   ")
	if err != nil {
		http.Error(rw, err.Error(), http.StatusInternalServerError)
		return
	}

	header.Set("Content-Length", strconv.Itoa(len(copied)))
	copyHeader(rw.Header(), header)
	rw.WriteHeader(code)

	n, err := rw.Write(copied)
	if err != nil {
		logrus.Errorf("Error writing: %s", err)
		return
	}
	if n != len(copied) {
		logrus.Errorf("Short write: wrote %d, expected %d", n, len(copied))
	}
}

func createTestEnv(t *testing.T, fn testSinkFn) Listener {
	pk, err := libtrust.GenerateECP256PrivateKey()
	if err != nil {
		t.Fatalf("error generating private key: %v", err)
	}

	sm, err = manifest.Sign(&m, pk)
	if err != nil {
		t.Fatalf("error signing manifest: %v", err)
	}

	payload, err = sm.Payload()
	if err != nil {
		t.Fatalf("error getting manifest payload: %v", err)
	}

	dgst, err = digest.FromBytes(payload)
	if err != nil {
		t.Fatalf("error digesting manifest payload: %v", err)
	}

	return NewBridge(ub, source, actor, request, fn)
}

// checkExerciseRegistry takes the registry through all of its operations,
// carrying out generic checks.
func checkExerciseRepository(t *testing.T, repository distribution.Repository) {
	// TODO(stevvooe): This would be a nice testutil function. Basically, it
	// takes the registry through a common set of operations. This could be
	// used to make cross-cutting updates by changing internals that affect
	// update counts. Basically, it would make writing tests a lot easier.
	ctx := context.Background()
	tag := "thetag"
	m := manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: repository.Name(),
		Tag:  tag,
	}

	blobs := repository.Blobs(ctx)
	for i := 0; i < 2; i++ {
		rs, ds, err := testutil.CreateRandomTarFile()
		if err != nil {
			t.Fatalf("error creating test layer: %v", err)
		}
		dgst := digest.Digest(ds)

		wr, err := blobs.Create(ctx)
		if err != nil {
			t.Fatalf("error creating layer upload: %v", err)
		}

		// Use the resumes, as well!
		wr, err = blobs.Resume(ctx, wr.ID())
		if err != nil {
			t.Fatalf("error resuming layer upload: %v", err)
		}

		io.Copy(wr, rs)

		if _, err := wr.Commit(ctx, distribution.Descriptor{Digest: dgst}); err != nil {
			t.Fatalf("unexpected error finishing upload: %v", err)
		}

		m.FSLayers = append(m.FSLayers, manifest.FSLayer{
			BlobSum: dgst,
		})

		// Then fetch the blobs
		if rc, err := blobs.Open(ctx, dgst); err != nil {
			t.Fatalf("error fetching layer: %v", err)
		} else {
			defer rc.Close()
		}
	}

	pk, err := libtrust.GenerateECP256PrivateKey()
	if err != nil {
		t.Fatalf("unexpected error generating key: %v", err)
	}

	sm, err := manifest.Sign(&m, pk)
	if err != nil {
		t.Fatalf("unexpected error signing manifest: %v", err)
	}

	manifests, err := repository.Manifests(ctx)
	if err != nil {
		t.Fatal(err.Error())
	}

	if err = manifests.Put(sm); err != nil {
		t.Fatalf("unexpected error putting the manifest: %v", err)
	}

	p, err := sm.Payload()
	if err != nil {
		t.Fatalf("unexpected error getting manifest payload: %v", err)
	}

	dgst, err := digest.FromBytes(p)
	if err != nil {
		t.Fatalf("unexpected error digesting manifest payload: %v", err)
	}

	fetchedByManifest, err := manifests.Get(dgst)
	if err != nil {
		t.Fatalf("unexpected error fetching manifest: %v", err)
	}

	if fetchedByManifest.Tag != sm.Tag {
		t.Fatalf("retrieved unexpected manifest: %v", err)
	}

	fetched, err := manifests.GetByTag(tag)
	if err != nil {
		t.Fatalf("unexpected error fetching manifest: %v", err)
	}

	if fetched.Tag != fetchedByManifest.Tag {
		t.Fatalf("retrieved unexpected manifest: %v", err)
	}
//.........这里部分代码省略.........

func TestManifestAPI(t *testing.T) {
	env := newTestEnv(t)

	imageName := "foo/bar"
	tag := "thetag"

	manifestURL, err := env.builder.BuildManifestURL(imageName, tag)
	if err != nil {
		t.Fatalf("unexpected error getting manifest url: %v", err)
	}

	// -----------------------------
	// Attempt to fetch the manifest
	resp, err := http.Get(manifestURL)
	if err != nil {
		t.Fatalf("unexpected error getting manifest: %v", err)
	}
	defer resp.Body.Close()

	checkResponse(t, "getting non-existent manifest", resp, http.StatusNotFound)
	checkBodyHasErrorCodes(t, "getting non-existent manifest", resp, v2.ErrorCodeManifestUnknown)

	tagsURL, err := env.builder.BuildTagsURL(imageName)
	if err != nil {
		t.Fatalf("unexpected error building tags url: %v", err)
	}

	resp, err = http.Get(tagsURL)
	if err != nil {
		t.Fatalf("unexpected error getting unknown tags: %v", err)
	}
	defer resp.Body.Close()

	// Check that we get an unknown repository error when asking for tags
	checkResponse(t, "getting unknown manifest tags", resp, http.StatusNotFound)
	checkBodyHasErrorCodes(t, "getting unknown manifest tags", resp, v2.ErrorCodeNameUnknown)

	// --------------------------------
	// Attempt to push unsigned manifest with missing layers
	unsignedManifest := &manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: imageName,
		Tag:  tag,
		FSLayers: []manifest.FSLayer{
			{
				BlobSum: "asdf",
			},
			{
				BlobSum: "qwer",
			},
		},
	}

	resp = putManifest(t, "putting unsigned manifest", manifestURL, unsignedManifest)
	defer resp.Body.Close()
	checkResponse(t, "posting unsigned manifest", resp, http.StatusBadRequest)
	_, p, counts := checkBodyHasErrorCodes(t, "getting unknown manifest tags", resp,
		v2.ErrorCodeManifestUnverified, v2.ErrorCodeBlobUnknown, v2.ErrorCodeDigestInvalid)

	expectedCounts := map[errcode.ErrorCode]int{
		v2.ErrorCodeManifestUnverified: 1,
		v2.ErrorCodeBlobUnknown:        2,
		v2.ErrorCodeDigestInvalid:      2,
	}

	if !reflect.DeepEqual(counts, expectedCounts) {
		t.Fatalf("unexpected number of error codes encountered: %v\n!=\n%v\n---\n%s", counts, expectedCounts, string(p))
	}

	// TODO(stevvooe): Add a test case where we take a mostly valid registry,
	// tamper with the content and ensure that we get a unverified manifest
	// error.

	// Push 2 random layers
	expectedLayers := make(map[digest.Digest]io.ReadSeeker)

	for i := range unsignedManifest.FSLayers {
		rs, dgstStr, err := testutil.CreateRandomTarFile()

		if err != nil {
			t.Fatalf("error creating random layer %d: %v", i, err)
		}
		dgst := digest.Digest(dgstStr)

		expectedLayers[dgst] = rs
		unsignedManifest.FSLayers[i].BlobSum = dgst

		uploadURLBase, _ := startPushLayer(t, env.builder, imageName)
		pushLayer(t, env.builder, imageName, dgst, uploadURLBase, rs)
	}

	// -------------------
	// Push the signed manifest with all layers pushed.
	signedManifest, err := manifest.Sign(unsignedManifest, env.pk)
	if err != nil {
		t.Fatalf("unexpected error signing manifest: %v", err)
	}

//.........这里部分代码省略.........

//.........这里部分代码省略.........
		}

		// break early if layer has already been seen in this image,
		// this prevents infinite loops on layers which loopback, this
		// cannot be prevented since layer IDs are not merkle hashes
		// TODO(dmcgowan): throw error if no valid use case is found
		if layersSeen[layer.ID] {
			break
		}

		logrus.Debugf("Pushing layer: %s", layer.ID)

		if layer.Config != nil && metadata.Image != layer.ID {
			if err := runconfig.Merge(&metadata, layer.Config); err != nil {
				return err
			}
		}

		var exists bool
		dgst, err := p.graph.GetLayerDigest(layer.ID)
		switch err {
		case nil:
			if p.layersPushed[dgst] {
				exists = true
				// break out of switch, it is already known that
				// the push is not needed and therefore doing a
				// stat is unnecessary
				break
			}
			_, err := p.repo.Blobs(context.Background()).Stat(context.Background(), dgst)
			switch err {
			case nil:
				exists = true
				out.Write(p.sf.FormatProgress(stringid.TruncateID(layer.ID), "Image already exists", nil))
			case distribution.ErrBlobUnknown:
				// nop
			default:
				out.Write(p.sf.FormatProgress(stringid.TruncateID(layer.ID), "Image push failed", nil))
				return err
			}
		case ErrDigestNotSet:
			// nop
		case digest.ErrDigestInvalidFormat, digest.ErrDigestUnsupported:
			return fmt.Errorf("error getting image checksum: %v", err)
		}

		// if digest was empty or not saved, or if blob does not exist on the remote repository,
		// then fetch it.
		if !exists {
			var pushDigest digest.Digest
			if pushDigest, err = p.pushV2Image(p.repo.Blobs(context.Background()), layer); err != nil {
				return err
			}
			if dgst == "" {
				// Cache new checksum
				if err := p.graph.SetLayerDigest(layer.ID, pushDigest); err != nil {
					return err
				}
			}
			dgst = pushDigest
		}

		// read v1Compatibility config, generate new if needed
		jsonData, err := p.graph.GenerateV1CompatibilityChain(layer.ID)
		if err != nil {
			return err
		}

		m.FSLayers = append(m.FSLayers, manifest.FSLayer{BlobSum: dgst})
		m.History = append(m.History, manifest.History{V1Compatibility: string(jsonData)})

		layersSeen[layer.ID] = true
		p.layersPushed[dgst] = true
	}

	// Fix parent chain if necessary
	if err = fixHistory(m); err != nil {
		return err
	}

	logrus.Infof("Signed manifest for %s:%s using daemon's key: %s", p.repo.Name(), tag, p.trustKey.KeyID())
	signed, err := manifest.Sign(m, p.trustKey)
	if err != nil {
		return err
	}

	manifestDigest, manifestSize, err := digestFromManifest(signed, p.repo.Name())
	if err != nil {
		return err
	}
	if manifestDigest != "" {
		out.Write(p.sf.FormatStatus("", "%s: digest: %s size: %d", tag, manifestDigest, manifestSize))
	}

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

func TestManifestStorage(t *testing.T) {
	env := newManifestStoreTestEnv(t, "foo/bar", "thetag")
	ctx := context.Background()
	ms, err := env.repository.Manifests(ctx)
	if err != nil {
		t.Fatal(err)
	}

	exists, err := ms.ExistsByTag(env.tag)
	if err != nil {
		t.Fatalf("unexpected error checking manifest existence: %v", err)
	}

	if exists {
		t.Fatalf("manifest should not exist")
	}

	if _, err := ms.GetByTag(env.tag); true {
		switch err.(type) {
		case distribution.ErrManifestUnknown:
			break
		default:
			t.Fatalf("expected manifest unknown error: %#v", err)
		}
	}

	m := manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: env.name,
		Tag:  env.tag,
	}

	// Build up some test layers and add them to the manifest, saving the
	// readseekers for upload later.
	testLayers := map[digest.Digest]io.ReadSeeker{}
	for i := 0; i < 2; i++ {
		rs, ds, err := testutil.CreateRandomTarFile()
		if err != nil {
			t.Fatalf("unexpected error generating test layer file")
		}
		dgst := digest.Digest(ds)

		testLayers[digest.Digest(dgst)] = rs
		m.FSLayers = append(m.FSLayers, manifest.FSLayer{
			BlobSum: dgst,
		})
	}

	pk, err := libtrust.GenerateECP256PrivateKey()
	if err != nil {
		t.Fatalf("unexpected error generating private key: %v", err)
	}

	sm, merr := manifest.Sign(&m, pk)
	if merr != nil {
		t.Fatalf("error signing manifest: %v", err)
	}

	err = ms.Put(sm)
	if err == nil {
		t.Fatalf("expected errors putting manifest with full verification")
	}

	switch err := err.(type) {
	case distribution.ErrManifestVerification:
		if len(err) != 2 {
			t.Fatalf("expected 2 verification errors: %#v", err)
		}

		for _, err := range err {
			if _, ok := err.(distribution.ErrManifestBlobUnknown); !ok {
				t.Fatalf("unexpected error type: %v", err)
			}
		}
	default:
		t.Fatalf("unexpected error verifying manifest: %v", err)
	}

	// Now, upload the layers that were missing!
	for dgst, rs := range testLayers {
		wr, err := env.repository.Blobs(env.ctx).Create(env.ctx)
		if err != nil {
			t.Fatalf("unexpected error creating test upload: %v", err)
		}

		if _, err := io.Copy(wr, rs); err != nil {
			t.Fatalf("unexpected error copying to upload: %v", err)
		}

		if _, err := wr.Commit(env.ctx, distribution.Descriptor{Digest: dgst}); err != nil {
			t.Fatalf("unexpected error finishing upload: %v", err)
		}
	}

	if err = ms.Put(sm); err != nil {
		t.Fatalf("unexpected error putting manifest: %v", err)
	}

//.........这里部分代码省略.........

func (p *v2Pusher) pushV2Tag(tag string) error {
	logrus.Debugf("Pushing repository: %s:%s", p.repo.Name(), tag)

	layerID, exists := p.localRepo[tag]
	if !exists {
		return fmt.Errorf("tag does not exist: %s", tag)
	}

	layer, err := p.graph.Get(layerID)
	if err != nil {
		return err
	}

	m := &manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name:         p.repo.Name(),
		Tag:          tag,
		Architecture: layer.Architecture,
		FSLayers:     []manifest.FSLayer{},
		History:      []manifest.History{},
	}

	var metadata runconfig.Config
	if layer != nil && layer.Config != nil {
		metadata = *layer.Config
	}

	out := p.config.OutStream

	for ; layer != nil; layer, err = p.graph.GetParent(layer) {
		if err != nil {
			return err
		}

		if p.layersSeen[layer.ID] {
			break
		}

		logrus.Debugf("Pushing layer: %s", layer.ID)

		if layer.Config != nil && metadata.Image != layer.ID {
			if err := runconfig.Merge(&metadata, layer.Config); err != nil {
				return err
			}
		}

		jsonData, err := p.graph.RawJSON(layer.ID)
		if err != nil {
			return fmt.Errorf("cannot retrieve the path for %s: %s", layer.ID, err)
		}

		var exists bool
		dgst, err := p.graph.GetDigest(layer.ID)
		switch err {
		case nil:
			_, err := p.repo.Blobs(nil).Stat(nil, dgst)
			switch err {
			case nil:
				exists = true
				out.Write(p.sf.FormatProgress(stringid.TruncateID(layer.ID), "Image already exists", nil))
			case distribution.ErrBlobUnknown:
				// nop
			default:
				out.Write(p.sf.FormatProgress(stringid.TruncateID(layer.ID), "Image push failed", nil))
				return err
			}
		case ErrDigestNotSet:
			// nop
		case digest.ErrDigestInvalidFormat, digest.ErrDigestUnsupported:
			return fmt.Errorf("error getting image checksum: %v", err)
		}

		// if digest was empty or not saved, or if blob does not exist on the remote repository,
		// then fetch it.
		if !exists {
			if pushDigest, err := p.pushV2Image(p.repo.Blobs(nil), layer); err != nil {
				return err
			} else if pushDigest != dgst {
				// Cache new checksum
				if err := p.graph.SetDigest(layer.ID, pushDigest); err != nil {
					return err
				}
				dgst = pushDigest
			}
		}

		m.FSLayers = append(m.FSLayers, manifest.FSLayer{BlobSum: dgst})
		m.History = append(m.History, manifest.History{V1Compatibility: string(jsonData)})

		p.layersSeen[layer.ID] = true
	}

	logrus.Infof("Signed manifest for %s:%s using daemon's key: %s", p.repo.Name(), tag, p.trustKey.KeyID())
	signed, err := manifest.Sign(m, p.trustKey)
	if err != nil {
		return err
	}

//.........这里部分代码省略.........

func TestManifestStorage(t *testing.T) {
	env := newManifestStoreTestEnv(t, "foo/bar", "thetag")
	ms := env.repository.Manifests()

	exists, err := ms.ExistsByTag(env.ctx, env.tag)
	if err != nil {
		t.Fatalf("unexpected error checking manifest existence: %v", err)
	}

	if exists {
		t.Fatalf("manifest should not exist")
	}

	if _, err := ms.GetByTag(env.ctx, env.tag); true {
		switch err.(type) {
		case distribution.ErrManifestUnknown:
			break
		default:
			t.Fatalf("expected manifest unknown error: %#v", err)
		}
	}

	m := manifest.Manifest{
		Versioned: manifest.Versioned{
			SchemaVersion: 1,
		},
		Name: env.name,
		Tag:  env.tag,
	}

	// Build up some test layers and add them to the manifest, saving the
	// readseekers for upload later.
	testLayers := map[digest.Digest]io.ReadSeeker{}
	for i := 0; i < 2; i++ {
		rs, ds, err := testutil.CreateRandomTarFile()
		if err != nil {
			t.Fatalf("unexpected error generating test layer file")
		}
		dgst := digest.Digest(ds)

		testLayers[digest.Digest(dgst)] = rs
		m.FSLayers = append(m.FSLayers, manifest.FSLayer{
			BlobSum: dgst,
		})
	}

	pk, err := libtrust.GenerateECP256PrivateKey()
	if err != nil {
		t.Fatalf("unexpected error generating private key: %v", err)
	}

	sm, err := manifest.Sign(&m, pk)
	if err != nil {
		t.Fatalf("error signing manifest: %v", err)
	}

	err = ms.Put(env.ctx, sm)
	if err == nil {
		t.Fatalf("expected errors putting manifest")
	}

	// TODO(stevvooe): We expect errors describing all of the missing layers.

	// Now, upload the layers that were missing!
	for dgst, rs := range testLayers {
		upload, err := env.repository.Layers().Upload()
		if err != nil {
			t.Fatalf("unexpected error creating test upload: %v", err)
		}

		if _, err := io.Copy(upload, rs); err != nil {
			t.Fatalf("unexpected error copying to upload: %v", err)
		}

		if _, err := upload.Finish(dgst); err != nil {
			t.Fatalf("unexpected error finishing upload: %v", err)
		}
	}

	if err = ms.Put(env.ctx, sm); err != nil {
		t.Fatalf("unexpected error putting manifest: %v", err)
	}

	exists, err = ms.ExistsByTag(env.ctx, env.tag)
	if err != nil {
		t.Fatalf("unexpected error checking manifest existence: %v", err)
	}

	if !exists {
		t.Fatalf("manifest should exist")
	}

	fetchedManifest, err := ms.GetByTag(env.ctx, env.tag)
	if err != nil {
		t.Fatalf("unexpected error fetching manifest: %v", err)
	}

	if !reflect.DeepEqual(fetchedManifest, sm) {
		t.Fatalf("fetched manifest not equal: %#v != %#v", fetchedManifest, sm)
	}
//.........这里部分代码省略.........