Initial checkin from CRI-O repo

Signed-off-by: Matthew Heon <matthew.heon@gmail.com>

41 files changed, 7761 insertions, 0 deletions

diff --git a/vendor/github.com/docker/distribution/LICENSE b/vendor/github.com/docker/distribution/LICENSE
new file mode 100644
index 000000000..e06d20818
--- /dev/null
+++ b/vendor/github.com/docker/distribution/LICENSE
@@ -0,0 +1,202 @@
+Apache License
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diff --git a/vendor/github.com/docker/distribution/README.md b/vendor/github.com/docker/distribution/README.md
new file mode 100644
index 000000000..998878850
--- /dev/null
+++ b/vendor/github.com/docker/distribution/README.md
@@ -0,0 +1,130 @@
+# Distribution
+
+The Docker toolset to pack, ship, store, and deliver content.
+
+This repository's main product is the Docker Registry 2.0 implementation
+for storing and distributing Docker images. It supersedes the
+[docker/docker-registry](https://github.com/docker/docker-registry)
+project with a new API design, focused around security and performance.
+
+<img src="https://www.docker.com/sites/default/files/oyster-registry-3.png" width=200px/>
+
+[![Circle CI](https://circleci.com/gh/docker/distribution/tree/master.svg?style=svg)](https://circleci.com/gh/docker/distribution/tree/master)
+[![GoDoc](https://godoc.org/github.com/docker/distribution?status.svg)](https://godoc.org/github.com/docker/distribution)
+
+This repository contains the following components:
+
+|**Component**       |Description                                                                                                                                                                                         |
+|--------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| **registry**       | An implementation of the [Docker Registry HTTP API V2](docs/spec/api.md) for use with docker 1.6+.                                                                                                  |
+| **libraries**      | A rich set of libraries for interacting with distribution components. Please see [godoc](https://godoc.org/github.com/docker/distribution) for details. **Note**: These libraries are **unstable**. |
+| **specifications** | _Distribution_ related specifications are available in [docs/spec](docs/spec)                                                                                                                        |
+| **documentation**  | Docker's full documentation set is available at [docs.docker.com](https://docs.docker.com). This repository [contains the subset](docs/) related just to the registry.                                                                                                                                          |
+
+### How does this integrate with Docker engine?
+
+This project should provide an implementation to a V2 API for use in the [Docker
+core project](https://github.com/docker/docker). The API should be embeddable
+and simplify the process of securely pulling and pushing content from `docker`
+daemons.
+
+### What are the long term goals of the Distribution project?
+
+The _Distribution_ project has the further long term goal of providing a
+secure tool chain for distributing content. The specifications, APIs and tools
+should be as useful with Docker as they are without.
+
+Our goal is to design a professional grade and extensible content distribution
+system that allow users to:
+
+* Enjoy an efficient, secured and reliable way to store, manage, package and
+  exchange content
+* Hack/roll their own on top of healthy open-source components
+* Implement their own home made solution through good specs, and solid
+  extensions mechanism.
+
+## More about Registry 2.0
+
+The new registry implementation provides the following benefits:
+
+- faster push and pull
+- new, more efficient implementation
+- simplified deployment
+- pluggable storage backend
+- webhook notifications
+
+For information on upcoming functionality, please see [ROADMAP.md](ROADMAP.md).
+
+### Who needs to deploy a registry?
+
+By default, Docker users pull images from Docker's public registry instance.
+[Installing Docker](https://docs.docker.com/engine/installation/) gives users this
+ability. Users can also push images to a repository on Docker's public registry,
+if they have a [Docker Hub](https://hub.docker.com/) account.
+
+For some users and even companies, this default behavior is sufficient. For
+others, it is not.
+
+For example, users with their own software products may want to maintain a
+registry for private, company images. Also, you may wish to deploy your own
+image repository for images used to test or in continuous integration. For these
+use cases and others, [deploying your own registry instance](https://github.com/docker/docker.github.io/blob/master/registry/deploying.md)
+may be the better choice.
+
+### Migration to Registry 2.0
+
+For those who have previously deployed their own registry based on the Registry
+1.0 implementation and wish to deploy a Registry 2.0 while retaining images,
+data migration is required. A tool to assist with migration efforts has been
+created. For more information see [docker/migrator](https://github.com/docker/migrator).
+
+## Contribute
+
+Please see [CONTRIBUTING.md](CONTRIBUTING.md) for details on how to contribute
+issues, fixes, and patches to this project. If you are contributing code, see
+the instructions for [building a development environment](BUILDING.md).
+
+## Support
+
+If any issues are encountered while using the _Distribution_ project, several
+avenues are available for support:
+
+<table>
+<tr>
+	<th align="left">
+	IRC
+	</th>
+	<td>
+	#docker-distribution on FreeNode
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Issue Tracker
+	</th>
+	<td>
+	github.com/docker/distribution/issues
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Google Groups
+	</th>
+	<td>
+	https://groups.google.com/a/dockerproject.org/forum/#!forum/distribution
+	</td>
+</tr>
+<tr>
+	<th align="left">
+	Mailing List
+	</th>
+	<td>
+	docker@dockerproject.org
+	</td>
+</tr>
+</table>
+
+
+## License
+
+This project is distributed under [Apache License, Version 2.0](LICENSE).
diff --git a/vendor/github.com/docker/distribution/blobs.go b/vendor/github.com/docker/distribution/blobs.go
new file mode 100644
index 000000000..01d309029
--- /dev/null
+++ b/vendor/github.com/docker/distribution/blobs.go
@@ -0,0 +1,257 @@
+package distribution
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/reference"
+	"github.com/opencontainers/go-digest"
+)
+
+var (
+	// ErrBlobExists returned when blob already exists
+	ErrBlobExists = errors.New("blob exists")
+
+	// ErrBlobDigestUnsupported when blob digest is an unsupported version.
+	ErrBlobDigestUnsupported = errors.New("unsupported blob digest")
+
+	// ErrBlobUnknown when blob is not found.
+	ErrBlobUnknown = errors.New("unknown blob")
+
+	// ErrBlobUploadUnknown returned when upload is not found.
+	ErrBlobUploadUnknown = errors.New("blob upload unknown")
+
+	// ErrBlobInvalidLength returned when the blob has an expected length on
+	// commit, meaning mismatched with the descriptor or an invalid value.
+	ErrBlobInvalidLength = errors.New("blob invalid length")
+)
+
+// ErrBlobInvalidDigest returned when digest check fails.
+type ErrBlobInvalidDigest struct {
+	Digest digest.Digest
+	Reason error
+}
+
+func (err ErrBlobInvalidDigest) Error() string {
+	return fmt.Sprintf("invalid digest for referenced layer: %v, %v",
+		err.Digest, err.Reason)
+}
+
+// ErrBlobMounted returned when a blob is mounted from another repository
+// instead of initiating an upload session.
+type ErrBlobMounted struct {
+	From       reference.Canonical
+	Descriptor Descriptor
+}
+
+func (err ErrBlobMounted) Error() string {
+	return fmt.Sprintf("blob mounted from: %v to: %v",
+		err.From, err.Descriptor)
+}
+
+// Descriptor describes targeted content. Used in conjunction with a blob
+// store, a descriptor can be used to fetch, store and target any kind of
+// blob. The struct also describes the wire protocol format. Fields should
+// only be added but never changed.
+type Descriptor struct {
+	// MediaType describe the type of the content. All text based formats are
+	// encoded as utf-8.
+	MediaType string `json:"mediaType,omitempty"`
+
+	// Size in bytes of content.
+	Size int64 `json:"size,omitempty"`
+
+	// Digest uniquely identifies the content. A byte stream can be verified
+	// against against this digest.
+	Digest digest.Digest `json:"digest,omitempty"`
+
+	// URLs contains the source URLs of this content.
+	URLs []string `json:"urls,omitempty"`
+
+	// NOTE: Before adding a field here, please ensure that all
+	// other options have been exhausted. Much of the type relationships
+	// depend on the simplicity of this type.
+}
+
+// Descriptor returns the descriptor, to make it satisfy the Describable
+// interface. Note that implementations of Describable are generally objects
+// which can be described, not simply descriptors; this exception is in place
+// to make it more convenient to pass actual descriptors to functions that
+// expect Describable objects.
+func (d Descriptor) Descriptor() Descriptor {
+	return d
+}
+
+// BlobStatter makes blob descriptors available by digest. The service may
+// provide a descriptor of a different digest if the provided digest is not
+// canonical.
+type BlobStatter interface {
+	// Stat provides metadata about a blob identified by the digest. If the
+	// blob is unknown to the describer, ErrBlobUnknown will be returned.
+	Stat(ctx context.Context, dgst digest.Digest) (Descriptor, error)
+}
+
+// BlobDeleter enables deleting blobs from storage.
+type BlobDeleter interface {
+	Delete(ctx context.Context, dgst digest.Digest) error
+}
+
+// BlobEnumerator enables iterating over blobs from storage
+type BlobEnumerator interface {
+	Enumerate(ctx context.Context, ingester func(dgst digest.Digest) error) error
+}
+
+// BlobDescriptorService manages metadata about a blob by digest. Most
+// implementations will not expose such an interface explicitly. Such mappings
+// should be maintained by interacting with the BlobIngester. Hence, this is
+// left off of BlobService and BlobStore.
+type BlobDescriptorService interface {
+	BlobStatter
+
+	// SetDescriptor assigns the descriptor to the digest. The provided digest and
+	// the digest in the descriptor must map to identical content but they may
+	// differ on their algorithm. The descriptor must have the canonical
+	// digest of the content and the digest algorithm must match the
+	// annotators canonical algorithm.
+	//
+	// Such a facility can be used to map blobs between digest domains, with
+	// the restriction that the algorithm of the descriptor must match the
+	// canonical algorithm (ie sha256) of the annotator.
+	SetDescriptor(ctx context.Context, dgst digest.Digest, desc Descriptor) error
+
+	// Clear enables descriptors to be unlinked
+	Clear(ctx context.Context, dgst digest.Digest) error
+}
+
+// BlobDescriptorServiceFactory creates middleware for BlobDescriptorService.
+type BlobDescriptorServiceFactory interface {
+	BlobAccessController(svc BlobDescriptorService) BlobDescriptorService
+}
+
+// ReadSeekCloser is the primary reader type for blob data, combining
+// io.ReadSeeker with io.Closer.
+type ReadSeekCloser interface {
+	io.ReadSeeker
+	io.Closer
+}
+
+// BlobProvider describes operations for getting blob data.
+type BlobProvider interface {
+	// Get returns the entire blob identified by digest along with the descriptor.
+	Get(ctx context.Context, dgst digest.Digest) ([]byte, error)
+
+	// Open provides a ReadSeekCloser to the blob identified by the provided
+	// descriptor. If the blob is not known to the service, an error will be
+	// returned.
+	Open(ctx context.Context, dgst digest.Digest) (ReadSeekCloser, error)
+}
+
+// BlobServer can serve blobs via http.
+type BlobServer interface {
+	// ServeBlob attempts to serve the blob, identified by dgst, via http. The
+	// service may decide to redirect the client elsewhere or serve the data
+	// directly.
+	//
+	// This handler only issues successful responses, such as 2xx or 3xx,
+	// meaning it serves data or issues a redirect. If the blob is not
+	// available, an error will be returned and the caller may still issue a
+	// response.
+	//
+	// The implementation may serve the same blob from a different digest
+	// domain. The appropriate headers will be set for the blob, unless they
+	// have already been set by the caller.
+	ServeBlob(ctx context.Context, w http.ResponseWriter, r *http.Request, dgst digest.Digest) error
+}
+
+// BlobIngester ingests blob data.
+type BlobIngester interface {
+	// Put inserts the content p into the blob service, returning a descriptor
+	// or an error.
+	Put(ctx context.Context, mediaType string, p []byte) (Descriptor, error)
+
+	// Create allocates a new blob writer to add a blob to this service. The
+	// returned handle can be written to and later resumed using an opaque
+	// identifier. With this approach, one can Close and Resume a BlobWriter
+	// multiple times until the BlobWriter is committed or cancelled.
+	Create(ctx context.Context, options ...BlobCreateOption) (BlobWriter, error)
+
+	// Resume attempts to resume a write to a blob, identified by an id.
+	Resume(ctx context.Context, id string) (BlobWriter, error)
+}
+
+// BlobCreateOption is a general extensible function argument for blob creation
+// methods. A BlobIngester may choose to honor any or none of the given
+// BlobCreateOptions, which can be specific to the implementation of the
+// BlobIngester receiving them.
+// TODO (brianbland): unify this with ManifestServiceOption in the future
+type BlobCreateOption interface {
+	Apply(interface{}) error
+}
+
+// CreateOptions is a collection of blob creation modifiers relevant to general
+// blob storage intended to be configured by the BlobCreateOption.Apply method.
+type CreateOptions struct {
+	Mount struct {
+		ShouldMount bool
+		From        reference.Canonical
+		// Stat allows to pass precalculated descriptor to link and return.
+		// Blob access check will be skipped if set.
+		Stat *Descriptor
+	}
+}
+
+// BlobWriter provides a handle for inserting data into a blob store.
+// Instances should be obtained from BlobWriteService.Writer and
+// BlobWriteService.Resume. If supported by the store, a writer can be
+// recovered with the id.
+type BlobWriter interface {
+	io.WriteCloser
+	io.ReaderFrom
+
+	// Size returns the number of bytes written to this blob.
+	Size() int64
+
+	// ID returns the identifier for this writer. The ID can be used with the
+	// Blob service to later resume the write.
+	ID() string
+
+	// StartedAt returns the time this blob write was started.
+	StartedAt() time.Time
+
+	// Commit completes the blob writer process. The content is verified
+	// against the provided provisional descriptor, which may result in an
+	// error. Depending on the implementation, written data may be validated
+	// against the provisional descriptor fields. If MediaType is not present,
+	// the implementation may reject the commit or assign "application/octet-
+	// stream" to the blob. The returned descriptor may have a different
+	// digest depending on the blob store, referred to as the canonical
+	// descriptor.
+	Commit(ctx context.Context, provisional Descriptor) (canonical Descriptor, err error)
+
+	// Cancel ends the blob write without storing any data and frees any
+	// associated resources. Any data written thus far will be lost. Cancel
+	// implementations should allow multiple calls even after a commit that
+	// result in a no-op. This allows use of Cancel in a defer statement,
+	// increasing the assurance that it is correctly called.
+	Cancel(ctx context.Context) error
+}
+
+// BlobService combines the operations to access, read and write blobs. This
+// can be used to describe remote blob services.
+type BlobService interface {
+	BlobStatter
+	BlobProvider
+	BlobIngester
+}
+
+// BlobStore represent the entire suite of blob related operations. Such an
+// implementation can access, read, write, delete and serve blobs.
+type BlobStore interface {
+	BlobService
+	BlobServer
+	BlobDeleter
+}
diff --git a/vendor/github.com/docker/distribution/context/context.go b/vendor/github.com/docker/distribution/context/context.go
new file mode 100644
index 000000000..23cbf5b54
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/context.go
@@ -0,0 +1,85 @@
+package context
+
+import (
+	"sync"
+
+	"github.com/docker/distribution/uuid"
+	"golang.org/x/net/context"
+)
+
+// Context is a copy of Context from the golang.org/x/net/context package.
+type Context interface {
+	context.Context
+}
+
+// instanceContext is a context that provides only an instance id. It is
+// provided as the main background context.
+type instanceContext struct {
+	Context
+	id   string    // id of context, logged as "instance.id"
+	once sync.Once // once protect generation of the id
+}
+
+func (ic *instanceContext) Value(key interface{}) interface{} {
+	if key == "instance.id" {
+		ic.once.Do(func() {
+			// We want to lazy initialize the UUID such that we don't
+			// call a random generator from the package initialization
+			// code. For various reasons random could not be available
+			// https://github.com/docker/distribution/issues/782
+			ic.id = uuid.Generate().String()
+		})
+		return ic.id
+	}
+
+	return ic.Context.Value(key)
+}
+
+var background = &instanceContext{
+	Context: context.Background(),
+}
+
+// Background returns a non-nil, empty Context. The background context
+// provides a single key, "instance.id" that is globally unique to the
+// process.
+func Background() Context {
+	return background
+}
+
+// WithValue returns a copy of parent in which the value associated with key is
+// val. Use context Values only for request-scoped data that transits processes
+// and APIs, not for passing optional parameters to functions.
+func WithValue(parent Context, key, val interface{}) Context {
+	return context.WithValue(parent, key, val)
+}
+
+// stringMapContext is a simple context implementation that checks a map for a
+// key, falling back to a parent if not present.
+type stringMapContext struct {
+	context.Context
+	m map[string]interface{}
+}
+
+// WithValues returns a context that proxies lookups through a map. Only
+// supports string keys.
+func WithValues(ctx context.Context, m map[string]interface{}) context.Context {
+	mo := make(map[string]interface{}, len(m)) // make our own copy.
+	for k, v := range m {
+		mo[k] = v
+	}
+
+	return stringMapContext{
+		Context: ctx,
+		m:       mo,
+	}
+}
+
+func (smc stringMapContext) Value(key interface{}) interface{} {
+	if ks, ok := key.(string); ok {
+		if v, ok := smc.m[ks]; ok {
+			return v
+		}
+	}
+
+	return smc.Context.Value(key)
+}
diff --git a/vendor/github.com/docker/distribution/context/doc.go b/vendor/github.com/docker/distribution/context/doc.go
new file mode 100644
index 000000000..9b623074e
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/doc.go
@@ -0,0 +1,89 @@
+// Package context provides several utilities for working with
+// golang.org/x/net/context in http requests. Primarily, the focus is on
+// logging relevant request information but this package is not limited to
+// that purpose.
+//
+// The easiest way to get started is to get the background context:
+//
+// 	ctx := context.Background()
+//
+// The returned context should be passed around your application and be the
+// root of all other context instances. If the application has a version, this
+// line should be called before anything else:
+//
+// 	ctx := context.WithVersion(context.Background(), version)
+//
+// The above will store the version in the context and will be available to
+// the logger.
+//
+// Logging
+//
+// The most useful aspect of this package is GetLogger. This function takes
+// any context.Context interface and returns the current logger from the
+// context. Canonical usage looks like this:
+//
+// 	GetLogger(ctx).Infof("something interesting happened")
+//
+// GetLogger also takes optional key arguments. The keys will be looked up in
+// the context and reported with the logger. The following example would
+// return a logger that prints the version with each log message:
+//
+// 	ctx := context.Context(context.Background(), "version", version)
+// 	GetLogger(ctx, "version").Infof("this log message has a version field")
+//
+// The above would print out a log message like this:
+//
+// 	INFO[0000] this log message has a version field        version=v2.0.0-alpha.2.m
+//
+// When used with WithLogger, we gain the ability to decorate the context with
+// loggers that have information from disparate parts of the call stack.
+// Following from the version example, we can build a new context with the
+// configured logger such that we always print the version field:
+//
+// 	ctx = WithLogger(ctx, GetLogger(ctx, "version"))
+//
+// Since the logger has been pushed to the context, we can now get the version
+// field for free with our log messages. Future calls to GetLogger on the new
+// context will have the version field:
+//
+// 	GetLogger(ctx).Infof("this log message has a version field")
+//
+// This becomes more powerful when we start stacking loggers. Let's say we
+// have the version logger from above but also want a request id. Using the
+// context above, in our request scoped function, we place another logger in
+// the context:
+//
+// 	ctx = context.WithValue(ctx, "http.request.id", "unique id") // called when building request context
+// 	ctx = WithLogger(ctx, GetLogger(ctx, "http.request.id"))
+//
+// When GetLogger is called on the new context, "http.request.id" will be
+// included as a logger field, along with the original "version" field:
+//
+// 	INFO[0000] this log message has a version field        http.request.id=unique id version=v2.0.0-alpha.2.m
+//
+// Note that this only affects the new context, the previous context, with the
+// version field, can be used independently. Put another way, the new logger,
+// added to the request context, is unique to that context and can have
+// request scoped variables.
+//
+// HTTP Requests
+//
+// This package also contains several methods for working with http requests.
+// The concepts are very similar to those described above. We simply place the
+// request in the context using WithRequest. This makes the request variables
+// available. GetRequestLogger can then be called to get request specific
+// variables in a log line:
+//
+// 	ctx = WithRequest(ctx, req)
+// 	GetRequestLogger(ctx).Infof("request variables")
+//
+// Like above, if we want to include the request data in all log messages in
+// the context, we push the logger to a new context and use that one:
+//
+// 	ctx = WithLogger(ctx, GetRequestLogger(ctx))
+//
+// The concept is fairly powerful and ensures that calls throughout the stack
+// can be traced in log messages. Using the fields like "http.request.id", one
+// can analyze call flow for a particular request with a simple grep of the
+// logs.
+package context
diff --git a/vendor/github.com/docker/distribution/context/http.go b/vendor/github.com/docker/distribution/context/http.go
new file mode 100644
index 000000000..7d65c8524
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/http.go
@@ -0,0 +1,366 @@
+package context
+
+import (
+	"errors"
+	"net"
+	"net/http"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/docker/distribution/uuid"
+	"github.com/gorilla/mux"
+	log "github.com/sirupsen/logrus"
+)
+
+// Common errors used with this package.
+var (
+	ErrNoRequestContext        = errors.New("no http request in context")
+	ErrNoResponseWriterContext = errors.New("no http response in context")
+)
+
+func parseIP(ipStr string) net.IP {
+	ip := net.ParseIP(ipStr)
+	if ip == nil {
+		log.Warnf("invalid remote IP address: %q", ipStr)
+	}
+	return ip
+}
+
+// RemoteAddr extracts the remote address of the request, taking into
+// account proxy headers.
+func RemoteAddr(r *http.Request) string {
+	if prior := r.Header.Get("X-Forwarded-For"); prior != "" {
+		proxies := strings.Split(prior, ",")
+		if len(proxies) > 0 {
+			remoteAddr := strings.Trim(proxies[0], " ")
+			if parseIP(remoteAddr) != nil {
+				return remoteAddr
+			}
+		}
+	}
+	// X-Real-Ip is less supported, but worth checking in the
+	// absence of X-Forwarded-For
+	if realIP := r.Header.Get("X-Real-Ip"); realIP != "" {
+		if parseIP(realIP) != nil {
+			return realIP
+		}
+	}
+
+	return r.RemoteAddr
+}
+
+// RemoteIP extracts the remote IP of the request, taking into
+// account proxy headers.
+func RemoteIP(r *http.Request) string {
+	addr := RemoteAddr(r)
+
+	// Try parsing it as "IP:port"
+	if ip, _, err := net.SplitHostPort(addr); err == nil {
+		return ip
+	}
+
+	return addr
+}
+
+// WithRequest places the request on the context. The context of the request
+// is assigned a unique id, available at "http.request.id". The request itself
+// is available at "http.request". Other common attributes are available under
+// the prefix "http.request.". If a request is already present on the context,
+// this method will panic.
+func WithRequest(ctx Context, r *http.Request) Context {
+	if ctx.Value("http.request") != nil {
+		// NOTE(stevvooe): This needs to be considered a programming error. It
+		// is unlikely that we'd want to have more than one request in
+		// context.
+		panic("only one request per context")
+	}
+
+	return &httpRequestContext{
+		Context:   ctx,
+		startedAt: time.Now(),
+		id:        uuid.Generate().String(),
+		r:         r,
+	}
+}
+
+// GetRequest returns the http request in the given context. Returns
+// ErrNoRequestContext if the context does not have an http request associated
+// with it.
+func GetRequest(ctx Context) (*http.Request, error) {
+	if r, ok := ctx.Value("http.request").(*http.Request); r != nil && ok {
+		return r, nil
+	}
+	return nil, ErrNoRequestContext
+}
+
+// GetRequestID attempts to resolve the current request id, if possible. An
+// error is return if it is not available on the context.
+func GetRequestID(ctx Context) string {
+	return GetStringValue(ctx, "http.request.id")
+}
+
+// WithResponseWriter returns a new context and response writer that makes
+// interesting response statistics available within the context.
+func WithResponseWriter(ctx Context, w http.ResponseWriter) (Context, http.ResponseWriter) {
+	if closeNotifier, ok := w.(http.CloseNotifier); ok {
+		irwCN := &instrumentedResponseWriterCN{
+			instrumentedResponseWriter: instrumentedResponseWriter{
+				ResponseWriter: w,
+				Context:        ctx,
+			},
+			CloseNotifier: closeNotifier,
+		}
+
+		return irwCN, irwCN
+	}
+
+	irw := instrumentedResponseWriter{
+		ResponseWriter: w,
+		Context:        ctx,
+	}
+	return &irw, &irw
+}
+
+// GetResponseWriter returns the http.ResponseWriter from the provided
+// context. If not present, ErrNoResponseWriterContext is returned. The
+// returned instance provides instrumentation in the context.
+func GetResponseWriter(ctx Context) (http.ResponseWriter, error) {
+	v := ctx.Value("http.response")
+
+	rw, ok := v.(http.ResponseWriter)
+	if !ok || rw == nil {
+		return nil, ErrNoResponseWriterContext
+	}
+
+	return rw, nil
+}
+
+// getVarsFromRequest let's us change request vars implementation for testing
+// and maybe future changes.
+var getVarsFromRequest = mux.Vars
+
+// WithVars extracts gorilla/mux vars and makes them available on the returned
+// context. Variables are available at keys with the prefix "vars.". For
+// example, if looking for the variable "name", it can be accessed as
+// "vars.name". Implementations that are accessing values need not know that
+// the underlying context is implemented with gorilla/mux vars.
+func WithVars(ctx Context, r *http.Request) Context {
+	return &muxVarsContext{
+		Context: ctx,
+		vars:    getVarsFromRequest(r),
+	}
+}
+
+// GetRequestLogger returns a logger that contains fields from the request in
+// the current context. If the request is not available in the context, no
+// fields will display. Request loggers can safely be pushed onto the context.
+func GetRequestLogger(ctx Context) Logger {
+	return GetLogger(ctx,
+		"http.request.id",
+		"http.request.method",
+		"http.request.host",
+		"http.request.uri",
+		"http.request.referer",
+		"http.request.useragent",
+		"http.request.remoteaddr",
+		"http.request.contenttype")
+}
+
+// GetResponseLogger reads the current response stats and builds a logger.
+// Because the values are read at call time, pushing a logger returned from
+// this function on the context will lead to missing or invalid data. Only
+// call this at the end of a request, after the response has been written.
+func GetResponseLogger(ctx Context) Logger {
+	l := getLogrusLogger(ctx,
+		"http.response.written",
+		"http.response.status",
+		"http.response.contenttype")
+
+	duration := Since(ctx, "http.request.startedat")
+
+	if duration > 0 {
+		l = l.WithField("http.response.duration", duration.String())
+	}
+
+	return l
+}
+
+// httpRequestContext makes information about a request available to context.
+type httpRequestContext struct {
+	Context
+
+	startedAt time.Time
+	id        string
+	r         *http.Request
+}
+
+// Value returns a keyed element of the request for use in the context. To get
+// the request itself, query "request". For other components, access them as
+// "request.<component>". For example, r.RequestURI
+func (ctx *httpRequestContext) Value(key interface{}) interface{} {
+	if keyStr, ok := key.(string); ok {
+		if keyStr == "http.request" {
+			return ctx.r
+		}
+
+		if !strings.HasPrefix(keyStr, "http.request.") {
+			goto fallback
+		}
+
+		parts := strings.Split(keyStr, ".")
+
+		if len(parts) != 3 {
+			goto fallback
+		}
+
+		switch parts[2] {
+		case "uri":
+			return ctx.r.RequestURI
+		case "remoteaddr":
+			return RemoteAddr(ctx.r)
+		case "method":
+			return ctx.r.Method
+		case "host":
+			return ctx.r.Host
+		case "referer":
+			referer := ctx.r.Referer()
+			if referer != "" {
+				return referer
+			}
+		case "useragent":
+			return ctx.r.UserAgent()
+		case "id":
+			return ctx.id
+		case "startedat":
+			return ctx.startedAt
+		case "contenttype":
+			ct := ctx.r.Header.Get("Content-Type")
+			if ct != "" {
+				return ct
+			}
+		}
+	}
+
+fallback:
+	return ctx.Context.Value(key)
+}
+
+type muxVarsContext struct {
+	Context
+	vars map[string]string
+}
+
+func (ctx *muxVarsContext) Value(key interface{}) interface{} {
+	if keyStr, ok := key.(string); ok {
+		if keyStr == "vars" {
+			return ctx.vars
+		}
+
+		if strings.HasPrefix(keyStr, "vars.") {
+			keyStr = strings.TrimPrefix(keyStr, "vars.")
+		}
+
+		if v, ok := ctx.vars[keyStr]; ok {
+			return v
+		}
+	}
+
+	return ctx.Context.Value(key)
+}
+
+// instrumentedResponseWriterCN provides response writer information in a
+// context. It implements http.CloseNotifier so that users can detect
+// early disconnects.
+type instrumentedResponseWriterCN struct {
+	instrumentedResponseWriter
+	http.CloseNotifier
+}
+
+// instrumentedResponseWriter provides response writer information in a
+// context. This variant is only used in the case where CloseNotifier is not
+// implemented by the parent ResponseWriter.
+type instrumentedResponseWriter struct {
+	http.ResponseWriter
+	Context
+
+	mu      sync.Mutex
+	status  int
+	written int64
+}
+
+func (irw *instrumentedResponseWriter) Write(p []byte) (n int, err error) {
+	n, err = irw.ResponseWriter.Write(p)
+
+	irw.mu.Lock()
+	irw.written += int64(n)
+
+	// Guess the likely status if not set.
+	if irw.status == 0 {
+		irw.status = http.StatusOK
+	}
+
+	irw.mu.Unlock()
+
+	return
+}
+
+func (irw *instrumentedResponseWriter) WriteHeader(status int) {
+	irw.ResponseWriter.WriteHeader(status)
+
+	irw.mu.Lock()
+	irw.status = status
+	irw.mu.Unlock()
+}
+
+func (irw *instrumentedResponseWriter) Flush() {
+	if flusher, ok := irw.ResponseWriter.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}
+
+func (irw *instrumentedResponseWriter) Value(key interface{}) interface{} {
+	if keyStr, ok := key.(string); ok {
+		if keyStr == "http.response" {
+			return irw
+		}
+
+		if !strings.HasPrefix(keyStr, "http.response.") {
+			goto fallback
+		}
+
+		parts := strings.Split(keyStr, ".")
+
+		if len(parts) != 3 {
+			goto fallback
+		}
+
+		irw.mu.Lock()
+		defer irw.mu.Unlock()
+
+		switch parts[2] {
+		case "written":
+			return irw.written
+		case "status":
+			return irw.status
+		case "contenttype":
+			contentType := irw.Header().Get("Content-Type")
+			if contentType != "" {
+				return contentType
+			}
+		}
+	}
+
+fallback:
+	return irw.Context.Value(key)
+}
+
+func (irw *instrumentedResponseWriterCN) Value(key interface{}) interface{} {
+	if keyStr, ok := key.(string); ok {
+		if keyStr == "http.response" {
+			return irw
+		}
+	}
+
+	return irw.instrumentedResponseWriter.Value(key)
+}
diff --git a/vendor/github.com/docker/distribution/context/logger.go b/vendor/github.com/docker/distribution/context/logger.go
new file mode 100644
index 000000000..86c5964e4
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/logger.go
@@ -0,0 +1,116 @@
+package context
+
+import (
+	"fmt"
+
+	"github.com/sirupsen/logrus"
+	"runtime"
+)
+
+// Logger provides a leveled-logging interface.
+type Logger interface {
+	// standard logger methods
+	Print(args ...interface{})
+	Printf(format string, args ...interface{})
+	Println(args ...interface{})
+
+	Fatal(args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Fatalln(args ...interface{})
+
+	Panic(args ...interface{})
+	Panicf(format string, args ...interface{})
+	Panicln(args ...interface{})
+
+	// Leveled methods, from logrus
+	Debug(args ...interface{})
+	Debugf(format string, args ...interface{})
+	Debugln(args ...interface{})
+
+	Error(args ...interface{})
+	Errorf(format string, args ...interface{})
+	Errorln(args ...interface{})
+
+	Info(args ...interface{})
+	Infof(format string, args ...interface{})
+	Infoln(args ...interface{})
+
+	Warn(args ...interface{})
+	Warnf(format string, args ...interface{})
+	Warnln(args ...interface{})
+}
+
+// WithLogger creates a new context with provided logger.
+func WithLogger(ctx Context, logger Logger) Context {
+	return WithValue(ctx, "logger", logger)
+}
+
+// GetLoggerWithField returns a logger instance with the specified field key
+// and value without affecting the context. Extra specified keys will be
+// resolved from the context.
+func GetLoggerWithField(ctx Context, key, value interface{}, keys ...interface{}) Logger {
+	return getLogrusLogger(ctx, keys...).WithField(fmt.Sprint(key), value)
+}
+
+// GetLoggerWithFields returns a logger instance with the specified fields
+// without affecting the context. Extra specified keys will be resolved from
+// the context.
+func GetLoggerWithFields(ctx Context, fields map[interface{}]interface{}, keys ...interface{}) Logger {
+	// must convert from interface{} -> interface{} to string -> interface{} for logrus.
+	lfields := make(logrus.Fields, len(fields))
+	for key, value := range fields {
+		lfields[fmt.Sprint(key)] = value
+	}
+
+	return getLogrusLogger(ctx, keys...).WithFields(lfields)
+}
+
+// GetLogger returns the logger from the current context, if present. If one
+// or more keys are provided, they will be resolved on the context and
+// included in the logger. While context.Value takes an interface, any key
+// argument passed to GetLogger will be passed to fmt.Sprint when expanded as
+// a logging key field. If context keys are integer constants, for example,
+// its recommended that a String method is implemented.
+func GetLogger(ctx Context, keys ...interface{}) Logger {
+	return getLogrusLogger(ctx, keys...)
+}
+
+// GetLogrusLogger returns the logrus logger for the context. If one more keys
+// are provided, they will be resolved on the context and included in the
+// logger. Only use this function if specific logrus functionality is
+// required.
+func getLogrusLogger(ctx Context, keys ...interface{}) *logrus.Entry {
+	var logger *logrus.Entry
+
+	// Get a logger, if it is present.
+	loggerInterface := ctx.Value("logger")
+	if loggerInterface != nil {
+		if lgr, ok := loggerInterface.(*logrus.Entry); ok {
+			logger = lgr
+		}
+	}
+
+	if logger == nil {
+		fields := logrus.Fields{}
+
+		// Fill in the instance id, if we have it.
+		instanceID := ctx.Value("instance.id")
+		if instanceID != nil {
+			fields["instance.id"] = instanceID
+		}
+
+		fields["go.version"] = runtime.Version()
+		// If no logger is found, just return the standard logger.
+		logger = logrus.StandardLogger().WithFields(fields)
+	}
+
+	fields := logrus.Fields{}
+	for _, key := range keys {
+		v := ctx.Value(key)
+		if v != nil {
+			fields[fmt.Sprint(key)] = v
+		}
+	}
+
+	return logger.WithFields(fields)
+}
diff --git a/vendor/github.com/docker/distribution/context/trace.go b/vendor/github.com/docker/distribution/context/trace.go
new file mode 100644
index 000000000..721964a84
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/trace.go
@@ -0,0 +1,104 @@
+package context
+
+import (
+	"runtime"
+	"time"
+
+	"github.com/docker/distribution/uuid"
+)
+
+// WithTrace allocates a traced timing span in a new context. This allows a
+// caller to track the time between calling WithTrace and the returned done
+// function. When the done function is called, a log message is emitted with a
+// "trace.duration" field, corresponding to the elapsed time and a
+// "trace.func" field, corresponding to the function that called WithTrace.
+//
+// The logging keys "trace.id" and "trace.parent.id" are provided to implement
+// dapper-like tracing. This function should be complemented with a WithSpan
+// method that could be used for tracing distributed RPC calls.
+//
+// The main benefit of this function is to post-process log messages or
+// intercept them in a hook to provide timing data. Trace ids and parent ids
+// can also be linked to provide call tracing, if so required.
+//
+// Here is an example of the usage:
+//
+// 	func timedOperation(ctx Context) {
+// 		ctx, done := WithTrace(ctx)
+// 		defer done("this will be the log message")
+// 		// ... function body ...
+// 	}
+//
+// If the function ran for roughly 1s, such a usage would emit a log message
+// as follows:
+//
+// 	INFO[0001] this will be the log message  trace.duration=1.004575763s trace.func=github.com/docker/distribution/context.traceOperation trace.id=<id> ...
+//
+// Notice that the function name is automatically resolved, along with the
+// package and a trace id is emitted that can be linked with parent ids.
+func WithTrace(ctx Context) (Context, func(format string, a ...interface{})) {
+	if ctx == nil {
+		ctx = Background()
+	}
+
+	pc, file, line, _ := runtime.Caller(1)
+	f := runtime.FuncForPC(pc)
+	ctx = &traced{
+		Context: ctx,
+		id:      uuid.Generate().String(),
+		start:   time.Now(),
+		parent:  GetStringValue(ctx, "trace.id"),
+		fnname:  f.Name(),
+		file:    file,
+		line:    line,
+	}
+
+	return ctx, func(format string, a ...interface{}) {
+		GetLogger(ctx,
+			"trace.duration",
+			"trace.id",
+			"trace.parent.id",
+			"trace.func",
+			"trace.file",
+			"trace.line").
+			Debugf(format, a...)
+	}
+}
+
+// traced represents a context that is traced for function call timing. It
+// also provides fast lookup for the various attributes that are available on
+// the trace.
+type traced struct {
+	Context
+	id     string
+	parent string
+	start  time.Time
+	fnname string
+	file   string
+	line   int
+}
+
+func (ts *traced) Value(key interface{}) interface{} {
+	switch key {
+	case "trace.start":
+		return ts.start
+	case "trace.duration":
+		return time.Since(ts.start)
+	case "trace.id":
+		return ts.id
+	case "trace.parent.id":
+		if ts.parent == "" {
+			return nil // must return nil to signal no parent.
+		}
+
+		return ts.parent
+	case "trace.func":
+		return ts.fnname
+	case "trace.file":
+		return ts.file
+	case "trace.line":
+		return ts.line
+	}
+
+	return ts.Context.Value(key)
+}
diff --git a/vendor/github.com/docker/distribution/context/util.go b/vendor/github.com/docker/distribution/context/util.go
new file mode 100644
index 000000000..cb9ef52e3
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/util.go
@@ -0,0 +1,24 @@
+package context
+
+import (
+	"time"
+)
+
+// Since looks up key, which should be a time.Time, and returns the duration
+// since that time. If the key is not found, the value returned will be zero.
+// This is helpful when inferring metrics related to context execution times.
+func Since(ctx Context, key interface{}) time.Duration {
+	if startedAt, ok := ctx.Value(key).(time.Time); ok {
+		return time.Since(startedAt)
+	}
+	return 0
+}
+
+// GetStringValue returns a string value from the context. The empty string
+// will be returned if not found.
+func GetStringValue(ctx Context, key interface{}) (value string) {
+	if valuev, ok := ctx.Value(key).(string); ok {
+		value = valuev
+	}
+	return value
+}
diff --git a/vendor/github.com/docker/distribution/context/version.go b/vendor/github.com/docker/distribution/context/version.go
new file mode 100644
index 000000000..746cda02e
--- /dev/null
+++ b/vendor/github.com/docker/distribution/context/version.go
@@ -0,0 +1,16 @@
+package context
+
+// WithVersion stores the application version in the context. The new context
+// gets a logger to ensure log messages are marked with the application
+// version.
+func WithVersion(ctx Context, version string) Context {
+	ctx = WithValue(ctx, "version", version)
+	// push a new logger onto the stack
+	return WithLogger(ctx, GetLogger(ctx, "version"))
+}
+
+// GetVersion returns the application version from the context. An empty
+// string may returned if the version was not set on the context.
+func GetVersion(ctx Context) string {
+	return GetStringValue(ctx, "version")
+}
diff --git a/vendor/github.com/docker/distribution/digestset/set.go b/vendor/github.com/docker/distribution/digestset/set.go
new file mode 100644
index 000000000..71327dca7
--- /dev/null
+++ b/vendor/github.com/docker/distribution/digestset/set.go
@@ -0,0 +1,247 @@
+package digestset
+
+import (
+	"errors"
+	"sort"
+	"strings"
+	"sync"
+
+	digest "github.com/opencontainers/go-digest"
+)
+
+var (
+	// ErrDigestNotFound is used when a matching digest
+	// could not be found in a set.
+	ErrDigestNotFound = errors.New("digest not found")
+
+	// ErrDigestAmbiguous is used when multiple digests
+	// are found in a set. None of the matching digests
+	// should be considered valid matches.
+	ErrDigestAmbiguous = errors.New("ambiguous digest string")
+)
+
+// Set is used to hold a unique set of digests which
+// may be easily referenced by easily  referenced by a string
+// representation of the digest as well as short representation.
+// The uniqueness of the short representation is based on other
+// digests in the set. If digests are omitted from this set,
+// collisions in a larger set may not be detected, therefore it
+// is important to always do short representation lookups on
+// the complete set of digests. To mitigate collisions, an
+// appropriately long short code should be used.
+type Set struct {
+	mutex   sync.RWMutex
+	entries digestEntries
+}
+
+// NewSet creates an empty set of digests
+// which may have digests added.
+func NewSet() *Set {
+	return &Set{
+		entries: digestEntries{},
+	}
+}
+
+// checkShortMatch checks whether two digests match as either whole
+// values or short values. This function does not test equality,
+// rather whether the second value could match against the first
+// value.
+func checkShortMatch(alg digest.Algorithm, hex, shortAlg, shortHex string) bool {
+	if len(hex) == len(shortHex) {
+		if hex != shortHex {
+			return false
+		}
+		if len(shortAlg) > 0 && string(alg) != shortAlg {
+			return false
+		}
+	} else if !strings.HasPrefix(hex, shortHex) {
+		return false
+	} else if len(shortAlg) > 0 && string(alg) != shortAlg {
+		return false
+	}
+	return true
+}
+
+// Lookup looks for a digest matching the given string representation.
+// If no digests could be found ErrDigestNotFound will be returned
+// with an empty digest value. If multiple matches are found
+// ErrDigestAmbiguous will be returned with an empty digest value.
+func (dst *Set) Lookup(d string) (digest.Digest, error) {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	if len(dst.entries) == 0 {
+		return "", ErrDigestNotFound
+	}
+	var (
+		searchFunc func(int) bool
+		alg        digest.Algorithm
+		hex        string
+	)
+	dgst, err := digest.Parse(d)
+	if err == digest.ErrDigestInvalidFormat {
+		hex = d
+		searchFunc = func(i int) bool {
+			return dst.entries[i].val >= d
+		}
+	} else {
+		hex = dgst.Hex()
+		alg = dgst.Algorithm()
+		searchFunc = func(i int) bool {
+			if dst.entries[i].val == hex {
+				return dst.entries[i].alg >= alg
+			}
+			return dst.entries[i].val >= hex
+		}
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	if idx == len(dst.entries) || !checkShortMatch(dst.entries[idx].alg, dst.entries[idx].val, string(alg), hex) {
+		return "", ErrDigestNotFound
+	}
+	if dst.entries[idx].alg == alg && dst.entries[idx].val == hex {
+		return dst.entries[idx].digest, nil
+	}
+	if idx+1 < len(dst.entries) && checkShortMatch(dst.entries[idx+1].alg, dst.entries[idx+1].val, string(alg), hex) {
+		return "", ErrDigestAmbiguous
+	}
+
+	return dst.entries[idx].digest, nil
+}
+
+// Add adds the given digest to the set. An error will be returned
+// if the given digest is invalid. If the digest already exists in the
+// set, this operation will be a no-op.
+func (dst *Set) Add(d digest.Digest) error {
+	if err := d.Validate(); err != nil {
+		return err
+	}
+	dst.mutex.Lock()
+	defer dst.mutex.Unlock()
+	entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d}
+	searchFunc := func(i int) bool {
+		if dst.entries[i].val == entry.val {
+			return dst.entries[i].alg >= entry.alg
+		}
+		return dst.entries[i].val >= entry.val
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	if idx == len(dst.entries) {
+		dst.entries = append(dst.entries, entry)
+		return nil
+	} else if dst.entries[idx].digest == d {
+		return nil
+	}
+
+	entries := append(dst.entries, nil)
+	copy(entries[idx+1:], entries[idx:len(entries)-1])
+	entries[idx] = entry
+	dst.entries = entries
+	return nil
+}
+
+// Remove removes the given digest from the set. An err will be
+// returned if the given digest is invalid. If the digest does
+// not exist in the set, this operation will be a no-op.
+func (dst *Set) Remove(d digest.Digest) error {
+	if err := d.Validate(); err != nil {
+		return err
+	}
+	dst.mutex.Lock()
+	defer dst.mutex.Unlock()
+	entry := &digestEntry{alg: d.Algorithm(), val: d.Hex(), digest: d}
+	searchFunc := func(i int) bool {
+		if dst.entries[i].val == entry.val {
+			return dst.entries[i].alg >= entry.alg
+		}
+		return dst.entries[i].val >= entry.val
+	}
+	idx := sort.Search(len(dst.entries), searchFunc)
+	// Not found if idx is after or value at idx is not digest
+	if idx == len(dst.entries) || dst.entries[idx].digest != d {
+		return nil
+	}
+
+	entries := dst.entries
+	copy(entries[idx:], entries[idx+1:])
+	entries = entries[:len(entries)-1]
+	dst.entries = entries
+
+	return nil
+}
+
+// All returns all the digests in the set
+func (dst *Set) All() []digest.Digest {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	retValues := make([]digest.Digest, len(dst.entries))
+	for i := range dst.entries {
+		retValues[i] = dst.entries[i].digest
+	}
+
+	return retValues
+}
+
+// ShortCodeTable returns a map of Digest to unique short codes. The
+// length represents the minimum value, the maximum length may be the
+// entire value of digest if uniqueness cannot be achieved without the
+// full value. This function will attempt to make short codes as short
+// as possible to be unique.
+func ShortCodeTable(dst *Set, length int) map[digest.Digest]string {
+	dst.mutex.RLock()
+	defer dst.mutex.RUnlock()
+	m := make(map[digest.Digest]string, len(dst.entries))
+	l := length
+	resetIdx := 0
+	for i := 0; i < len(dst.entries); i++ {
+		var short string
+		extended := true
+		for extended {
+			extended = false
+			if len(dst.entries[i].val) <= l {
+				short = dst.entries[i].digest.String()
+			} else {
+				short = dst.entries[i].val[:l]
+				for j := i + 1; j < len(dst.entries); j++ {
+					if checkShortMatch(dst.entries[j].alg, dst.entries[j].val, "", short) {
+						if j > resetIdx {
+							resetIdx = j
+						}
+						extended = true
+					} else {
+						break
+					}
+				}
+				if extended {
+					l++
+				}
+			}
+		}
+		m[dst.entries[i].digest] = short
+		if i >= resetIdx {
+			l = length
+		}
+	}
+	return m
+}
+
+type digestEntry struct {
+	alg    digest.Algorithm
+	val    string
+	digest digest.Digest
+}
+
+type digestEntries []*digestEntry
+
+func (d digestEntries) Len() int {
+	return len(d)
+}
+
+func (d digestEntries) Less(i, j int) bool {
+	if d[i].val != d[j].val {
+		return d[i].val < d[j].val
+	}
+	return d[i].alg < d[j].alg
+}
+
+func (d digestEntries) Swap(i, j int) {
+	d[i], d[j] = d[j], d[i]
+}
diff --git a/vendor/github.com/docker/distribution/doc.go b/vendor/github.com/docker/distribution/doc.go
new file mode 100644
index 000000000..bdd8cb708
--- /dev/null
+++ b/vendor/github.com/docker/distribution/doc.go
@@ -0,0 +1,7 @@
+// Package distribution will define the interfaces for the components of
+// docker distribution. The goal is to allow users to reliably package, ship
+// and store content related to docker images.
+//
+// This is currently a work in progress. More details are available in the
+// README.md.
+package distribution
diff --git a/vendor/github.com/docker/distribution/errors.go b/vendor/github.com/docker/distribution/errors.go
new file mode 100644
index 000000000..020d33258
--- /dev/null
+++ b/vendor/github.com/docker/distribution/errors.go
@@ -0,0 +1,115 @@
+package distribution
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/opencontainers/go-digest"
+)
+
+// ErrAccessDenied is returned when an access to a requested resource is
+// denied.
+var ErrAccessDenied = errors.New("access denied")
+
+// ErrManifestNotModified is returned when a conditional manifest GetByTag
+// returns nil due to the client indicating it has the latest version
+var ErrManifestNotModified = errors.New("manifest not modified")
+
+// ErrUnsupported is returned when an unimplemented or unsupported action is
+// performed
+var ErrUnsupported = errors.New("operation unsupported")
+
+// ErrTagUnknown is returned if the given tag is not known by the tag service
+type ErrTagUnknown struct {
+	Tag string
+}
+
+func (err ErrTagUnknown) Error() string {
+	return fmt.Sprintf("unknown tag=%s", err.Tag)
+}
+
+// ErrRepositoryUnknown is returned if the named repository is not known by
+// the registry.
+type ErrRepositoryUnknown struct {
+	Name string
+}
+
+func (err ErrRepositoryUnknown) Error() string {
+	return fmt.Sprintf("unknown repository name=%s", err.Name)
+}
+
+// ErrRepositoryNameInvalid should be used to denote an invalid repository
+// name. Reason may set, indicating the cause of invalidity.
+type ErrRepositoryNameInvalid struct {
+	Name   string
+	Reason error
+}
+
+func (err ErrRepositoryNameInvalid) Error() string {
+	return fmt.Sprintf("repository name %q invalid: %v", err.Name, err.Reason)
+}
+
+// ErrManifestUnknown is returned if the manifest is not known by the
+// registry.
+type ErrManifestUnknown struct {
+	Name string
+	Tag  string
+}
+
+func (err ErrManifestUnknown) Error() string {
+	return fmt.Sprintf("unknown manifest name=%s tag=%s", err.Name, err.Tag)
+}
+
+// ErrManifestUnknownRevision is returned when a manifest cannot be found by
+// revision within a repository.
+type ErrManifestUnknownRevision struct {
+	Name     string
+	Revision digest.Digest
+}
+
+func (err ErrManifestUnknownRevision) Error() string {
+	return fmt.Sprintf("unknown manifest name=%s revision=%s", err.Name, err.Revision)
+}
+
+// ErrManifestUnverified is returned when the registry is unable to verify
+// the manifest.
+type ErrManifestUnverified struct{}
+
+func (ErrManifestUnverified) Error() string {
+	return "unverified manifest"
+}
+
+// ErrManifestVerification provides a type to collect errors encountered
+// during manifest verification. Currently, it accepts errors of all types,
+// but it may be narrowed to those involving manifest verification.
+type ErrManifestVerification []error
+
+func (errs ErrManifestVerification) Error() string {
+	var parts []string
+	for _, err := range errs {
+		parts = append(parts, err.Error())
+	}
+
+	return fmt.Sprintf("errors verifying manifest: %v", strings.Join(parts, ","))
+}
+
+// ErrManifestBlobUnknown returned when a referenced blob cannot be found.
+type ErrManifestBlobUnknown struct {
+	Digest digest.Digest
+}
+
+func (err ErrManifestBlobUnknown) Error() string {
+	return fmt.Sprintf("unknown blob %v on manifest", err.Digest)
+}
+
+// ErrManifestNameInvalid should be used to denote an invalid manifest
+// name. Reason may set, indicating the cause of invalidity.
+type ErrManifestNameInvalid struct {
+	Name   string
+	Reason error
+}
+
+func (err ErrManifestNameInvalid) Error() string {
+	return fmt.Sprintf("manifest name %q invalid: %v", err.Name, err.Reason)
+}
diff --git a/vendor/github.com/docker/distribution/manifests.go b/vendor/github.com/docker/distribution/manifests.go
new file mode 100644
index 000000000..2c99f25d3
--- /dev/null
+++ b/vendor/github.com/docker/distribution/manifests.go
@@ -0,0 +1,125 @@
+package distribution
+
+import (
+	"fmt"
+	"mime"
+
+	"github.com/docker/distribution/context"
+	"github.com/opencontainers/go-digest"
+)
+
+// Manifest represents a registry object specifying a set of
+// references and an optional target
+type Manifest interface {
+	// References returns a list of objects which make up this manifest.
+	// A reference is anything which can be represented by a
+	// distribution.Descriptor. These can consist of layers, resources or other
+	// manifests.
+	//
+	// While no particular order is required, implementations should return
+	// them from highest to lowest priority. For example, one might want to
+	// return the base layer before the top layer.
+	References() []Descriptor
+
+	// Payload provides the serialized format of the manifest, in addition to
+	// the media type.
+	Payload() (mediaType string, payload []byte, err error)
+}
+
+// ManifestBuilder creates a manifest allowing one to include dependencies.
+// Instances can be obtained from a version-specific manifest package.  Manifest
+// specific data is passed into the function which creates the builder.
+type ManifestBuilder interface {
+	// Build creates the manifest from his builder.
+	Build(ctx context.Context) (Manifest, error)
+
+	// References returns a list of objects which have been added to this
+	// builder. The dependencies are returned in the order they were added,
+	// which should be from base to head.
+	References() []Descriptor
+
+	// AppendReference includes the given object in the manifest after any
+	// existing dependencies. If the add fails, such as when adding an
+	// unsupported dependency, an error may be returned.
+	//
+	// The destination of the reference is dependent on the manifest type and
+	// the dependency type.
+	AppendReference(dependency Describable) error
+}
+
+// ManifestService describes operations on image manifests.
+type ManifestService interface {
+	// Exists returns true if the manifest exists.
+	Exists(ctx context.Context, dgst digest.Digest) (bool, error)
+
+	// Get retrieves the manifest specified by the given digest
+	Get(ctx context.Context, dgst digest.Digest, options ...ManifestServiceOption) (Manifest, error)
+
+	// Put creates or updates the given manifest returning the manifest digest
+	Put(ctx context.Context, manifest Manifest, options ...ManifestServiceOption) (digest.Digest, error)
+
+	// Delete removes the manifest specified by the given digest. Deleting
+	// a manifest that doesn't exist will return ErrManifestNotFound
+	Delete(ctx context.Context, dgst digest.Digest) error
+}
+
+// ManifestEnumerator enables iterating over manifests
+type ManifestEnumerator interface {
+	// Enumerate calls ingester for each manifest.
+	Enumerate(ctx context.Context, ingester func(digest.Digest) error) error
+}
+
+// Describable is an interface for descriptors
+type Describable interface {
+	Descriptor() Descriptor
+}
+
+// ManifestMediaTypes returns the supported media types for manifests.
+func ManifestMediaTypes() (mediaTypes []string) {
+	for t := range mappings {
+		if t != "" {
+			mediaTypes = append(mediaTypes, t)
+		}
+	}
+	return
+}
+
+// UnmarshalFunc implements manifest unmarshalling a given MediaType
+type UnmarshalFunc func([]byte) (Manifest, Descriptor, error)
+
+var mappings = make(map[string]UnmarshalFunc, 0)
+
+// UnmarshalManifest looks up manifest unmarshal functions based on
+// MediaType
+func UnmarshalManifest(ctHeader string, p []byte) (Manifest, Descriptor, error) {
+	// Need to look up by the actual media type, not the raw contents of
+	// the header. Strip semicolons and anything following them.
+	var mediaType string
+	if ctHeader != "" {
+		var err error
+		mediaType, _, err = mime.ParseMediaType(ctHeader)
+		if err != nil {
+			return nil, Descriptor{}, err
+		}
+	}
+
+	unmarshalFunc, ok := mappings[mediaType]
+	if !ok {
+		unmarshalFunc, ok = mappings[""]
+		if !ok {
+			return nil, Descriptor{}, fmt.Errorf("unsupported manifest media type and no default available: %s", mediaType)
+		}
+	}
+
+	return unmarshalFunc(p)
+}
+
+// RegisterManifestSchema registers an UnmarshalFunc for a given schema type.  This
+// should be called from specific
+func RegisterManifestSchema(mediaType string, u UnmarshalFunc) error {
+	if _, ok := mappings[mediaType]; ok {
+		return fmt.Errorf("manifest media type registration would overwrite existing: %s", mediaType)
+	}
+	mappings[mediaType] = u
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/reference/helpers.go b/vendor/github.com/docker/distribution/reference/helpers.go
new file mode 100644
index 000000000..978df7eab
--- /dev/null
+++ b/vendor/github.com/docker/distribution/reference/helpers.go
@@ -0,0 +1,42 @@
+package reference
+
+import "path"
+
+// IsNameOnly returns true if reference only contains a repo name.
+func IsNameOnly(ref Named) bool {
+	if _, ok := ref.(NamedTagged); ok {
+		return false
+	}
+	if _, ok := ref.(Canonical); ok {
+		return false
+	}
+	return true
+}
+
+// FamiliarName returns the familiar name string
+// for the given named, familiarizing if needed.
+func FamiliarName(ref Named) string {
+	if nn, ok := ref.(normalizedNamed); ok {
+		return nn.Familiar().Name()
+	}
+	return ref.Name()
+}
+
+// FamiliarString returns the familiar string representation
+// for the given reference, familiarizing if needed.
+func FamiliarString(ref Reference) string {
+	if nn, ok := ref.(normalizedNamed); ok {
+		return nn.Familiar().String()
+	}
+	return ref.String()
+}
+
+// FamiliarMatch reports whether ref matches the specified pattern.
+// See https://godoc.org/path#Match for supported patterns.
+func FamiliarMatch(pattern string, ref Reference) (bool, error) {
+	matched, err := path.Match(pattern, FamiliarString(ref))
+	if namedRef, isNamed := ref.(Named); isNamed && !matched {
+		matched, _ = path.Match(pattern, FamiliarName(namedRef))
+	}
+	return matched, err
+}
diff --git a/vendor/github.com/docker/distribution/reference/normalize.go b/vendor/github.com/docker/distribution/reference/normalize.go
new file mode 100644
index 000000000..2d71fc5e9
--- /dev/null
+++ b/vendor/github.com/docker/distribution/reference/normalize.go
@@ -0,0 +1,170 @@
+package reference
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/docker/distribution/digestset"
+	"github.com/opencontainers/go-digest"
+)
+
+var (
+	legacyDefaultDomain = "index.docker.io"
+	defaultDomain       = "docker.io"
+	officialRepoName    = "library"
+	defaultTag          = "latest"
+)
+
+// normalizedNamed represents a name which has been
+// normalized and has a familiar form. A familiar name
+// is what is used in Docker UI. An example normalized
+// name is "docker.io/library/ubuntu" and corresponding
+// familiar name of "ubuntu".
+type normalizedNamed interface {
+	Named
+	Familiar() Named
+}
+
+// ParseNormalizedNamed parses a string into a named reference
+// transforming a familiar name from Docker UI to a fully
+// qualified reference. If the value may be an identifier
+// use ParseAnyReference.
+func ParseNormalizedNamed(s string) (Named, error) {
+	if ok := anchoredIdentifierRegexp.MatchString(s); ok {
+		return nil, fmt.Errorf("invalid repository name (%s), cannot specify 64-byte hexadecimal strings", s)
+	}
+	domain, remainder := splitDockerDomain(s)
+	var remoteName string
+	if tagSep := strings.IndexRune(remainder, ':'); tagSep > -1 {
+		remoteName = remainder[:tagSep]
+	} else {
+		remoteName = remainder
+	}
+	if strings.ToLower(remoteName) != remoteName {
+		return nil, errors.New("invalid reference format: repository name must be lowercase")
+	}
+
+	ref, err := Parse(domain + "/" + remainder)
+	if err != nil {
+		return nil, err
+	}
+	named, isNamed := ref.(Named)
+	if !isNamed {
+		return nil, fmt.Errorf("reference %s has no name", ref.String())
+	}
+	return named, nil
+}
+
+// splitDockerDomain splits a repository name to domain and remotename string.
+// If no valid domain is found, the default domain is used. Repository name
+// needs to be already validated before.
+func splitDockerDomain(name string) (domain, remainder string) {
+	i := strings.IndexRune(name, '/')
+	if i == -1 || (!strings.ContainsAny(name[:i], ".:") && name[:i] != "localhost") {
+		domain, remainder = defaultDomain, name
+	} else {
+		domain, remainder = name[:i], name[i+1:]
+	}
+	if domain == legacyDefaultDomain {
+		domain = defaultDomain
+	}
+	if domain == defaultDomain && !strings.ContainsRune(remainder, '/') {
+		remainder = officialRepoName + "/" + remainder
+	}
+	return
+}
+
+// familiarizeName returns a shortened version of the name familiar
+// to to the Docker UI. Familiar names have the default domain
+// "docker.io" and "library/" repository prefix removed.
+// For example, "docker.io/library/redis" will have the familiar
+// name "redis" and "docker.io/dmcgowan/myapp" will be "dmcgowan/myapp".
+// Returns a familiarized named only reference.
+func familiarizeName(named namedRepository) repository {
+	repo := repository{
+		domain: named.Domain(),
+		path:   named.Path(),
+	}
+
+	if repo.domain == defaultDomain {
+		repo.domain = ""
+		// Handle official repositories which have the pattern "library/<official repo name>"
+		if split := strings.Split(repo.path, "/"); len(split) == 2 && split[0] == officialRepoName {
+			repo.path = split[1]
+		}
+	}
+	return repo
+}
+
+func (r reference) Familiar() Named {
+	return reference{
+		namedRepository: familiarizeName(r.namedRepository),
+		tag:             r.tag,
+		digest:          r.digest,
+	}
+}
+
+func (r repository) Familiar() Named {
+	return familiarizeName(r)
+}
+
+func (t taggedReference) Familiar() Named {
+	return taggedReference{
+		namedRepository: familiarizeName(t.namedRepository),
+		tag:             t.tag,
+	}
+}
+
+func (c canonicalReference) Familiar() Named {
+	return canonicalReference{
+		namedRepository: familiarizeName(c.namedRepository),
+		digest:          c.digest,
+	}
+}
+
+// TagNameOnly adds the default tag "latest" to a reference if it only has
+// a repo name.
+func TagNameOnly(ref Named) Named {
+	if IsNameOnly(ref) {
+		namedTagged, err := WithTag(ref, defaultTag)
+		if err != nil {
+			// Default tag must be valid, to create a NamedTagged
+			// type with non-validated input the WithTag function
+			// should be used instead
+			panic(err)
+		}
+		return namedTagged
+	}
+	return ref
+}
+
+// ParseAnyReference parses a reference string as a possible identifier,
+// full digest, or familiar name.
+func ParseAnyReference(ref string) (Reference, error) {
+	if ok := anchoredIdentifierRegexp.MatchString(ref); ok {
+		return digestReference("sha256:" + ref), nil
+	}
+	if dgst, err := digest.Parse(ref); err == nil {
+		return digestReference(dgst), nil
+	}
+
+	return ParseNormalizedNamed(ref)
+}
+
+// ParseAnyReferenceWithSet parses a reference string as a possible short
+// identifier to be matched in a digest set, a full digest, or familiar name.
+func ParseAnyReferenceWithSet(ref string, ds *digestset.Set) (Reference, error) {
+	if ok := anchoredShortIdentifierRegexp.MatchString(ref); ok {
+		dgst, err := ds.Lookup(ref)
+		if err == nil {
+			return digestReference(dgst), nil
+		}
+	} else {
+		if dgst, err := digest.Parse(ref); err == nil {
+			return digestReference(dgst), nil
+		}
+	}
+
+	return ParseNormalizedNamed(ref)
+}
diff --git a/vendor/github.com/docker/distribution/reference/reference.go b/vendor/github.com/docker/distribution/reference/reference.go
new file mode 100644
index 000000000..2f66cca87
--- /dev/null
+++ b/vendor/github.com/docker/distribution/reference/reference.go
@@ -0,0 +1,433 @@
+// Package reference provides a general type to represent any way of referencing images within the registry.
+// Its main purpose is to abstract tags and digests (content-addressable hash).
+//
+// Grammar
+//
+// 	reference                       := name [ ":" tag ] [ "@" digest ]
+//	name                            := [domain '/'] path-component ['/' path-component]*
+//	domain                          := domain-component ['.' domain-component]* [':' port-number]
+//	domain-component                := /([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9])/
+//	port-number                     := /[0-9]+/
+//	path-component                  := alpha-numeric [separator alpha-numeric]*
+// 	alpha-numeric                   := /[a-z0-9]+/
+//	separator                       := /[_.]|__|[-]*/
+//
+//	tag                             := /[\w][\w.-]{0,127}/
+//
+//	digest                          := digest-algorithm ":" digest-hex
+//	digest-algorithm                := digest-algorithm-component [ digest-algorithm-separator digest-algorithm-component ]*
+//	digest-algorithm-separator      := /[+.-_]/
+//	digest-algorithm-component      := /[A-Za-z][A-Za-z0-9]*/
+//	digest-hex                      := /[0-9a-fA-F]{32,}/ ; At least 128 bit digest value
+//
+//	identifier                      := /[a-f0-9]{64}/
+//	short-identifier                := /[a-f0-9]{6,64}/
+package reference
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+
+	"github.com/opencontainers/go-digest"
+)
+
+const (
+	// NameTotalLengthMax is the maximum total number of characters in a repository name.
+	NameTotalLengthMax = 255
+)
+
+var (
+	// ErrReferenceInvalidFormat represents an error while trying to parse a string as a reference.
+	ErrReferenceInvalidFormat = errors.New("invalid reference format")
+
+	// ErrTagInvalidFormat represents an error while trying to parse a string as a tag.
+	ErrTagInvalidFormat = errors.New("invalid tag format")
+
+	// ErrDigestInvalidFormat represents an error while trying to parse a string as a tag.
+	ErrDigestInvalidFormat = errors.New("invalid digest format")
+
+	// ErrNameContainsUppercase is returned for invalid repository names that contain uppercase characters.
+	ErrNameContainsUppercase = errors.New("repository name must be lowercase")
+
+	// ErrNameEmpty is returned for empty, invalid repository names.
+	ErrNameEmpty = errors.New("repository name must have at least one component")
+
+	// ErrNameTooLong is returned when a repository name is longer than NameTotalLengthMax.
+	ErrNameTooLong = fmt.Errorf("repository name must not be more than %v characters", NameTotalLengthMax)
+
+	// ErrNameNotCanonical is returned when a name is not canonical.
+	ErrNameNotCanonical = errors.New("repository name must be canonical")
+)
+
+// Reference is an opaque object reference identifier that may include
+// modifiers such as a hostname, name, tag, and digest.
+type Reference interface {
+	// String returns the full reference
+	String() string
+}
+
+// Field provides a wrapper type for resolving correct reference types when
+// working with encoding.
+type Field struct {
+	reference Reference
+}
+
+// AsField wraps a reference in a Field for encoding.
+func AsField(reference Reference) Field {
+	return Field{reference}
+}
+
+// Reference unwraps the reference type from the field to
+// return the Reference object. This object should be
+// of the appropriate type to further check for different
+// reference types.
+func (f Field) Reference() Reference {
+	return f.reference
+}
+
+// MarshalText serializes the field to byte text which
+// is the string of the reference.
+func (f Field) MarshalText() (p []byte, err error) {
+	return []byte(f.reference.String()), nil
+}
+
+// UnmarshalText parses text bytes by invoking the
+// reference parser to ensure the appropriately
+// typed reference object is wrapped by field.
+func (f *Field) UnmarshalText(p []byte) error {
+	r, err := Parse(string(p))
+	if err != nil {
+		return err
+	}
+
+	f.reference = r
+	return nil
+}
+
+// Named is an object with a full name
+type Named interface {
+	Reference
+	Name() string
+}
+
+// Tagged is an object which has a tag
+type Tagged interface {
+	Reference
+	Tag() string
+}
+
+// NamedTagged is an object including a name and tag.
+type NamedTagged interface {
+	Named
+	Tag() string
+}
+
+// Digested is an object which has a digest
+// in which it can be referenced by
+type Digested interface {
+	Reference
+	Digest() digest.Digest
+}
+
+// Canonical reference is an object with a fully unique
+// name including a name with domain and digest
+type Canonical interface {
+	Named
+	Digest() digest.Digest
+}
+
+// namedRepository is a reference to a repository with a name.
+// A namedRepository has both domain and path components.
+type namedRepository interface {
+	Named
+	Domain() string
+	Path() string
+}
+
+// Domain returns the domain part of the Named reference
+func Domain(named Named) string {
+	if r, ok := named.(namedRepository); ok {
+		return r.Domain()
+	}
+	domain, _ := splitDomain(named.Name())
+	return domain
+}
+
+// Path returns the name without the domain part of the Named reference
+func Path(named Named) (name string) {
+	if r, ok := named.(namedRepository); ok {
+		return r.Path()
+	}
+	_, path := splitDomain(named.Name())
+	return path
+}
+
+func splitDomain(name string) (string, string) {
+	match := anchoredNameRegexp.FindStringSubmatch(name)
+	if len(match) != 3 {
+		return "", name
+	}
+	return match[1], match[2]
+}
+
+// SplitHostname splits a named reference into a
+// hostname and name string. If no valid hostname is
+// found, the hostname is empty and the full value
+// is returned as name
+// DEPRECATED: Use Domain or Path
+func SplitHostname(named Named) (string, string) {
+	if r, ok := named.(namedRepository); ok {
+		return r.Domain(), r.Path()
+	}
+	return splitDomain(named.Name())
+}
+
+// Parse parses s and returns a syntactically valid Reference.
+// If an error was encountered it is returned, along with a nil Reference.
+// NOTE: Parse will not handle short digests.
+func Parse(s string) (Reference, error) {
+	matches := ReferenceRegexp.FindStringSubmatch(s)
+	if matches == nil {
+		if s == "" {
+			return nil, ErrNameEmpty
+		}
+		if ReferenceRegexp.FindStringSubmatch(strings.ToLower(s)) != nil {
+			return nil, ErrNameContainsUppercase
+		}
+		return nil, ErrReferenceInvalidFormat
+	}
+
+	if len(matches[1]) > NameTotalLengthMax {
+		return nil, ErrNameTooLong
+	}
+
+	var repo repository
+
+	nameMatch := anchoredNameRegexp.FindStringSubmatch(matches[1])
+	if nameMatch != nil && len(nameMatch) == 3 {
+		repo.domain = nameMatch[1]
+		repo.path = nameMatch[2]
+	} else {
+		repo.domain = ""
+		repo.path = matches[1]
+	}
+
+	ref := reference{
+		namedRepository: repo,
+		tag:             matches[2],
+	}
+	if matches[3] != "" {
+		var err error
+		ref.digest, err = digest.Parse(matches[3])
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	r := getBestReferenceType(ref)
+	if r == nil {
+		return nil, ErrNameEmpty
+	}
+
+	return r, nil
+}
+
+// ParseNamed parses s and returns a syntactically valid reference implementing
+// the Named interface. The reference must have a name and be in the canonical
+// form, otherwise an error is returned.
+// If an error was encountered it is returned, along with a nil Reference.
+// NOTE: ParseNamed will not handle short digests.
+func ParseNamed(s string) (Named, error) {
+	named, err := ParseNormalizedNamed(s)
+	if err != nil {
+		return nil, err
+	}
+	if named.String() != s {
+		return nil, ErrNameNotCanonical
+	}
+	return named, nil
+}
+
+// WithName returns a named object representing the given string. If the input
+// is invalid ErrReferenceInvalidFormat will be returned.
+func WithName(name string) (Named, error) {
+	if len(name) > NameTotalLengthMax {
+		return nil, ErrNameTooLong
+	}
+
+	match := anchoredNameRegexp.FindStringSubmatch(name)
+	if match == nil || len(match) != 3 {
+		return nil, ErrReferenceInvalidFormat
+	}
+	return repository{
+		domain: match[1],
+		path:   match[2],
+	}, nil
+}
+
+// WithTag combines the name from "name" and the tag from "tag" to form a
+// reference incorporating both the name and the tag.
+func WithTag(name Named, tag string) (NamedTagged, error) {
+	if !anchoredTagRegexp.MatchString(tag) {
+		return nil, ErrTagInvalidFormat
+	}
+	var repo repository
+	if r, ok := name.(namedRepository); ok {
+		repo.domain = r.Domain()
+		repo.path = r.Path()
+	} else {
+		repo.path = name.Name()
+	}
+	if canonical, ok := name.(Canonical); ok {
+		return reference{
+			namedRepository: repo,
+			tag:             tag,
+			digest:          canonical.Digest(),
+		}, nil
+	}
+	return taggedReference{
+		namedRepository: repo,
+		tag:             tag,
+	}, nil
+}
+
+// WithDigest combines the name from "name" and the digest from "digest" to form
+// a reference incorporating both the name and the digest.
+func WithDigest(name Named, digest digest.Digest) (Canonical, error) {
+	if !anchoredDigestRegexp.MatchString(digest.String()) {
+		return nil, ErrDigestInvalidFormat
+	}
+	var repo repository
+	if r, ok := name.(namedRepository); ok {
+		repo.domain = r.Domain()
+		repo.path = r.Path()
+	} else {
+		repo.path = name.Name()
+	}
+	if tagged, ok := name.(Tagged); ok {
+		return reference{
+			namedRepository: repo,
+			tag:             tagged.Tag(),
+			digest:          digest,
+		}, nil
+	}
+	return canonicalReference{
+		namedRepository: repo,
+		digest:          digest,
+	}, nil
+}
+
+// TrimNamed removes any tag or digest from the named reference.
+func TrimNamed(ref Named) Named {
+	domain, path := SplitHostname(ref)
+	return repository{
+		domain: domain,
+		path:   path,
+	}
+}
+
+func getBestReferenceType(ref reference) Reference {
+	if ref.Name() == "" {
+		// Allow digest only references
+		if ref.digest != "" {
+			return digestReference(ref.digest)
+		}
+		return nil
+	}
+	if ref.tag == "" {
+		if ref.digest != "" {
+			return canonicalReference{
+				namedRepository: ref.namedRepository,
+				digest:          ref.digest,
+			}
+		}
+		return ref.namedRepository
+	}
+	if ref.digest == "" {
+		return taggedReference{
+			namedRepository: ref.namedRepository,
+			tag:             ref.tag,
+		}
+	}
+
+	return ref
+}
+
+type reference struct {
+	namedRepository
+	tag    string
+	digest digest.Digest
+}
+
+func (r reference) String() string {
+	return r.Name() + ":" + r.tag + "@" + r.digest.String()
+}
+
+func (r reference) Tag() string {
+	return r.tag
+}
+
+func (r reference) Digest() digest.Digest {
+	return r.digest
+}
+
+type repository struct {
+	domain string
+	path   string
+}
+
+func (r repository) String() string {
+	return r.Name()
+}
+
+func (r repository) Name() string {
+	if r.domain == "" {
+		return r.path
+	}
+	return r.domain + "/" + r.path
+}
+
+func (r repository) Domain() string {
+	return r.domain
+}
+
+func (r repository) Path() string {
+	return r.path
+}
+
+type digestReference digest.Digest
+
+func (d digestReference) String() string {
+	return digest.Digest(d).String()
+}
+
+func (d digestReference) Digest() digest.Digest {
+	return digest.Digest(d)
+}
+
+type taggedReference struct {
+	namedRepository
+	tag string
+}
+
+func (t taggedReference) String() string {
+	return t.Name() + ":" + t.tag
+}
+
+func (t taggedReference) Tag() string {
+	return t.tag
+}
+
+type canonicalReference struct {
+	namedRepository
+	digest digest.Digest
+}
+
+func (c canonicalReference) String() string {
+	return c.Name() + "@" + c.digest.String()
+}
+
+func (c canonicalReference) Digest() digest.Digest {
+	return c.digest
+}
diff --git a/vendor/github.com/docker/distribution/reference/regexp.go b/vendor/github.com/docker/distribution/reference/regexp.go
new file mode 100644
index 000000000..786034932
--- /dev/null
+++ b/vendor/github.com/docker/distribution/reference/regexp.go
@@ -0,0 +1,143 @@
+package reference
+
+import "regexp"
+
+var (
+	// alphaNumericRegexp defines the alpha numeric atom, typically a
+	// component of names. This only allows lower case characters and digits.
+	alphaNumericRegexp = match(`[a-z0-9]+`)
+
+	// separatorRegexp defines the separators allowed to be embedded in name
+	// components. This allow one period, one or two underscore and multiple
+	// dashes.
+	separatorRegexp = match(`(?:[._]|__|[-]*)`)
+
+	// nameComponentRegexp restricts registry path component names to start
+	// with at least one letter or number, with following parts able to be
+	// separated by one period, one or two underscore and multiple dashes.
+	nameComponentRegexp = expression(
+		alphaNumericRegexp,
+		optional(repeated(separatorRegexp, alphaNumericRegexp)))
+
+	// domainComponentRegexp restricts the registry domain component of a
+	// repository name to start with a component as defined by DomainRegexp
+	// and followed by an optional port.
+	domainComponentRegexp = match(`(?:[a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9-]*[a-zA-Z0-9])`)
+
+	// DomainRegexp defines the structure of potential domain components
+	// that may be part of image names. This is purposely a subset of what is
+	// allowed by DNS to ensure backwards compatibility with Docker image
+	// names.
+	DomainRegexp = expression(
+		domainComponentRegexp,
+		optional(repeated(literal(`.`), domainComponentRegexp)),
+		optional(literal(`:`), match(`[0-9]+`)))
+
+	// TagRegexp matches valid tag names. From docker/docker:graph/tags.go.
+	TagRegexp = match(`[\w][\w.-]{0,127}`)
+
+	// anchoredTagRegexp matches valid tag names, anchored at the start and
+	// end of the matched string.
+	anchoredTagRegexp = anchored(TagRegexp)
+
+	// DigestRegexp matches valid digests.
+	DigestRegexp = match(`[A-Za-z][A-Za-z0-9]*(?:[-_+.][A-Za-z][A-Za-z0-9]*)*[:][[:xdigit:]]{32,}`)
+
+	// anchoredDigestRegexp matches valid digests, anchored at the start and
+	// end of the matched string.
+	anchoredDigestRegexp = anchored(DigestRegexp)
+
+	// NameRegexp is the format for the name component of references. The
+	// regexp has capturing groups for the domain and name part omitting
+	// the separating forward slash from either.
+	NameRegexp = expression(
+		optional(DomainRegexp, literal(`/`)),
+		nameComponentRegexp,
+		optional(repeated(literal(`/`), nameComponentRegexp)))
+
+	// anchoredNameRegexp is used to parse a name value, capturing the
+	// domain and trailing components.
+	anchoredNameRegexp = anchored(
+		optional(capture(DomainRegexp), literal(`/`)),
+		capture(nameComponentRegexp,
+			optional(repeated(literal(`/`), nameComponentRegexp))))
+
+	// ReferenceRegexp is the full supported format of a reference. The regexp
+	// is anchored and has capturing groups for name, tag, and digest
+	// components.
+	ReferenceRegexp = anchored(capture(NameRegexp),
+		optional(literal(":"), capture(TagRegexp)),
+		optional(literal("@"), capture(DigestRegexp)))
+
+	// IdentifierRegexp is the format for string identifier used as a
+	// content addressable identifier using sha256. These identifiers
+	// are like digests without the algorithm, since sha256 is used.
+	IdentifierRegexp = match(`([a-f0-9]{64})`)
+
+	// ShortIdentifierRegexp is the format used to represent a prefix
+	// of an identifier. A prefix may be used to match a sha256 identifier
+	// within a list of trusted identifiers.
+	ShortIdentifierRegexp = match(`([a-f0-9]{6,64})`)
+
+	// anchoredIdentifierRegexp is used to check or match an
+	// identifier value, anchored at start and end of string.
+	anchoredIdentifierRegexp = anchored(IdentifierRegexp)
+
+	// anchoredShortIdentifierRegexp is used to check if a value
+	// is a possible identifier prefix, anchored at start and end
+	// of string.
+	anchoredShortIdentifierRegexp = anchored(ShortIdentifierRegexp)
+)
+
+// match compiles the string to a regular expression.
+var match = regexp.MustCompile
+
+// literal compiles s into a literal regular expression, escaping any regexp
+// reserved characters.
+func literal(s string) *regexp.Regexp {
+	re := match(regexp.QuoteMeta(s))
+
+	if _, complete := re.LiteralPrefix(); !complete {
+		panic("must be a literal")
+	}
+
+	return re
+}
+
+// expression defines a full expression, where each regular expression must
+// follow the previous.
+func expression(res ...*regexp.Regexp) *regexp.Regexp {
+	var s string
+	for _, re := range res {
+		s += re.String()
+	}
+
+	return match(s)
+}
+
+// optional wraps the expression in a non-capturing group and makes the
+// production optional.
+func optional(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(group(expression(res...)).String() + `?`)
+}
+
+// repeated wraps the regexp in a non-capturing group to get one or more
+// matches.
+func repeated(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(group(expression(res...)).String() + `+`)
+}
+
+// group wraps the regexp in a non-capturing group.
+func group(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`(?:` + expression(res...).String() + `)`)
+}
+
+// capture wraps the expression in a capturing group.
+func capture(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`(` + expression(res...).String() + `)`)
+}
+
+// anchored anchors the regular expression by adding start and end delimiters.
+func anchored(res ...*regexp.Regexp) *regexp.Regexp {
+	return match(`^` + expression(res...).String() + `$`)
+}
diff --git a/vendor/github.com/docker/distribution/registry.go b/vendor/github.com/docker/distribution/registry.go
new file mode 100644
index 000000000..1da1d533f
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry.go
@@ -0,0 +1,97 @@
+package distribution
+
+import (
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/reference"
+)
+
+// Scope defines the set of items that match a namespace.
+type Scope interface {
+	// Contains returns true if the name belongs to the namespace.
+	Contains(name string) bool
+}
+
+type fullScope struct{}
+
+func (f fullScope) Contains(string) bool {
+	return true
+}
+
+// GlobalScope represents the full namespace scope which contains
+// all other scopes.
+var GlobalScope = Scope(fullScope{})
+
+// Namespace represents a collection of repositories, addressable by name.
+// Generally, a namespace is backed by a set of one or more services,
+// providing facilities such as registry access, trust, and indexing.
+type Namespace interface {
+	// Scope describes the names that can be used with this Namespace. The
+	// global namespace will have a scope that matches all names. The scope
+	// effectively provides an identity for the namespace.
+	Scope() Scope
+
+	// Repository should return a reference to the named repository. The
+	// registry may or may not have the repository but should always return a
+	// reference.
+	Repository(ctx context.Context, name reference.Named) (Repository, error)
+
+	// Repositories fills 'repos' with a lexicographically sorted catalog of repositories
+	// up to the size of 'repos' and returns the value 'n' for the number of entries
+	// which were filled.  'last' contains an offset in the catalog, and 'err' will be
+	// set to io.EOF if there are no more entries to obtain.
+	Repositories(ctx context.Context, repos []string, last string) (n int, err error)
+
+	// Blobs returns a blob enumerator to access all blobs
+	Blobs() BlobEnumerator
+
+	// BlobStatter returns a BlobStatter to control
+	BlobStatter() BlobStatter
+}
+
+// RepositoryEnumerator describes an operation to enumerate repositories
+type RepositoryEnumerator interface {
+	Enumerate(ctx context.Context, ingester func(string) error) error
+}
+
+// ManifestServiceOption is a function argument for Manifest Service methods
+type ManifestServiceOption interface {
+	Apply(ManifestService) error
+}
+
+// WithTag allows a tag to be passed into Put
+func WithTag(tag string) ManifestServiceOption {
+	return WithTagOption{tag}
+}
+
+// WithTagOption holds a tag
+type WithTagOption struct{ Tag string }
+
+// Apply conforms to the ManifestServiceOption interface
+func (o WithTagOption) Apply(m ManifestService) error {
+	// no implementation
+	return nil
+}
+
+// Repository is a named collection of manifests and layers.
+type Repository interface {
+	// Named returns the name of the repository.
+	Named() reference.Named
+
+	// Manifests returns a reference to this repository's manifest service.
+	// with the supplied options applied.
+	Manifests(ctx context.Context, options ...ManifestServiceOption) (ManifestService, error)
+
+	// Blobs returns a reference to this repository's blob service.
+	Blobs(ctx context.Context) BlobStore
+
+	// TODO(stevvooe): The above BlobStore return can probably be relaxed to
+	// be a BlobService for use with clients. This will allow such
+	// implementations to avoid implementing ServeBlob.
+
+	// Tags returns a reference to this repositories tag service
+	Tags(ctx context.Context) TagService
+}
+
+// TODO(stevvooe): Must add close methods to all these. May want to change the
+// way instances are created to better reflect internal dependency
+// relationships.
diff --git a/vendor/github.com/docker/distribution/registry/api/errcode/errors.go b/vendor/github.com/docker/distribution/registry/api/errcode/errors.go
new file mode 100644
index 000000000..6d9bb4b62
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/errcode/errors.go
@@ -0,0 +1,267 @@
+package errcode
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// ErrorCoder is the base interface for ErrorCode and Error allowing
+// users of each to just call ErrorCode to get the real ID of each
+type ErrorCoder interface {
+	ErrorCode() ErrorCode
+}
+
+// ErrorCode represents the error type. The errors are serialized via strings
+// and the integer format may change and should *never* be exported.
+type ErrorCode int
+
+var _ error = ErrorCode(0)
+
+// ErrorCode just returns itself
+func (ec ErrorCode) ErrorCode() ErrorCode {
+	return ec
+}
+
+// Error returns the ID/Value
+func (ec ErrorCode) Error() string {
+	// NOTE(stevvooe): Cannot use message here since it may have unpopulated args.
+	return strings.ToLower(strings.Replace(ec.String(), "_", " ", -1))
+}
+
+// Descriptor returns the descriptor for the error code.
+func (ec ErrorCode) Descriptor() ErrorDescriptor {
+	d, ok := errorCodeToDescriptors[ec]
+
+	if !ok {
+		return ErrorCodeUnknown.Descriptor()
+	}
+
+	return d
+}
+
+// String returns the canonical identifier for this error code.
+func (ec ErrorCode) String() string {
+	return ec.Descriptor().Value
+}
+
+// Message returned the human-readable error message for this error code.
+func (ec ErrorCode) Message() string {
+	return ec.Descriptor().Message
+}
+
+// MarshalText encodes the receiver into UTF-8-encoded text and returns the
+// result.
+func (ec ErrorCode) MarshalText() (text []byte, err error) {
+	return []byte(ec.String()), nil
+}
+
+// UnmarshalText decodes the form generated by MarshalText.
+func (ec *ErrorCode) UnmarshalText(text []byte) error {
+	desc, ok := idToDescriptors[string(text)]
+
+	if !ok {
+		desc = ErrorCodeUnknown.Descriptor()
+	}
+
+	*ec = desc.Code
+
+	return nil
+}
+
+// WithMessage creates a new Error struct based on the passed-in info and
+// overrides the Message property.
+func (ec ErrorCode) WithMessage(message string) Error {
+	return Error{
+		Code:    ec,
+		Message: message,
+	}
+}
+
+// WithDetail creates a new Error struct based on the passed-in info and
+// set the Detail property appropriately
+func (ec ErrorCode) WithDetail(detail interface{}) Error {
+	return Error{
+		Code:    ec,
+		Message: ec.Message(),
+	}.WithDetail(detail)
+}
+
+// WithArgs creates a new Error struct and sets the Args slice
+func (ec ErrorCode) WithArgs(args ...interface{}) Error {
+	return Error{
+		Code:    ec,
+		Message: ec.Message(),
+	}.WithArgs(args...)
+}
+
+// Error provides a wrapper around ErrorCode with extra Details provided.
+type Error struct {
+	Code    ErrorCode   `json:"code"`
+	Message string      `json:"message"`
+	Detail  interface{} `json:"detail,omitempty"`
+
+	// TODO(duglin): See if we need an "args" property so we can do the
+	// variable substitution right before showing the message to the user
+}
+
+var _ error = Error{}
+
+// ErrorCode returns the ID/Value of this Error
+func (e Error) ErrorCode() ErrorCode {
+	return e.Code
+}
+
+// Error returns a human readable representation of the error.
+func (e Error) Error() string {
+	return fmt.Sprintf("%s: %s", e.Code.Error(), e.Message)
+}
+
+// WithDetail will return a new Error, based on the current one, but with
+// some Detail info added
+func (e Error) WithDetail(detail interface{}) Error {
+	return Error{
+		Code:    e.Code,
+		Message: e.Message,
+		Detail:  detail,
+	}
+}
+
+// WithArgs uses the passed-in list of interface{} as the substitution
+// variables in the Error's Message string, but returns a new Error
+func (e Error) WithArgs(args ...interface{}) Error {
+	return Error{
+		Code:    e.Code,
+		Message: fmt.Sprintf(e.Code.Message(), args...),
+		Detail:  e.Detail,
+	}
+}
+
+// ErrorDescriptor provides relevant information about a given error code.
+type ErrorDescriptor struct {
+	// Code is the error code that this descriptor describes.
+	Code ErrorCode
+
+	// Value provides a unique, string key, often captilized with
+	// underscores, to identify the error code. This value is used as the
+	// keyed value when serializing api errors.
+	Value string
+
+	// Message is a short, human readable decription of the error condition
+	// included in API responses.
+	Message string
+
+	// Description provides a complete account of the errors purpose, suitable
+	// for use in documentation.
+	Description string
+
+	// HTTPStatusCode provides the http status code that is associated with
+	// this error condition.
+	HTTPStatusCode int
+}
+
+// ParseErrorCode returns the value by the string error code.
+// `ErrorCodeUnknown` will be returned if the error is not known.
+func ParseErrorCode(value string) ErrorCode {
+	ed, ok := idToDescriptors[value]
+	if ok {
+		return ed.Code
+	}
+
+	return ErrorCodeUnknown
+}
+
+// Errors provides the envelope for multiple errors and a few sugar methods
+// for use within the application.
+type Errors []error
+
+var _ error = Errors{}
+
+func (errs Errors) Error() string {
+	switch len(errs) {
+	case 0:
+		return "<nil>"
+	case 1:
+		return errs[0].Error()
+	default:
+		msg := "errors:\n"
+		for _, err := range errs {
+			msg += err.Error() + "\n"
+		}
+		return msg
+	}
+}
+
+// Len returns the current number of errors.
+func (errs Errors) Len() int {
+	return len(errs)
+}
+
+// MarshalJSON converts slice of error, ErrorCode or Error into a
+// slice of Error - then serializes
+func (errs Errors) MarshalJSON() ([]byte, error) {
+	var tmpErrs struct {
+		Errors []Error `json:"errors,omitempty"`
+	}
+
+	for _, daErr := range errs {
+		var err Error
+
+		switch daErr.(type) {
+		case ErrorCode:
+			err = daErr.(ErrorCode).WithDetail(nil)
+		case Error:
+			err = daErr.(Error)
+		default:
+			err = ErrorCodeUnknown.WithDetail(daErr)
+
+		}
+
+		// If the Error struct was setup and they forgot to set the
+		// Message field (meaning its "") then grab it from the ErrCode
+		msg := err.Message
+		if msg == "" {
+			msg = err.Code.Message()
+		}
+
+		tmpErrs.Errors = append(tmpErrs.Errors, Error{
+			Code:    err.Code,
+			Message: msg,
+			Detail:  err.Detail,
+		})
+	}
+
+	return json.Marshal(tmpErrs)
+}
+
+// UnmarshalJSON deserializes []Error and then converts it into slice of
+// Error or ErrorCode
+func (errs *Errors) UnmarshalJSON(data []byte) error {
+	var tmpErrs struct {
+		Errors []Error
+	}
+
+	if err := json.Unmarshal(data, &tmpErrs); err != nil {
+		return err
+	}
+
+	var newErrs Errors
+	for _, daErr := range tmpErrs.Errors {
+		// If Message is empty or exactly matches the Code's message string
+		// then just use the Code, no need for a full Error struct
+		if daErr.Detail == nil && (daErr.Message == "" || daErr.Message == daErr.Code.Message()) {
+			// Error's w/o details get converted to ErrorCode
+			newErrs = append(newErrs, daErr.Code)
+		} else {
+			// Error's w/ details are untouched
+			newErrs = append(newErrs, Error{
+				Code:    daErr.Code,
+				Message: daErr.Message,
+				Detail:  daErr.Detail,
+			})
+		}
+	}
+
+	*errs = newErrs
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/errcode/handler.go b/vendor/github.com/docker/distribution/registry/api/errcode/handler.go
new file mode 100644
index 000000000..49a64a86e
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/errcode/handler.go
@@ -0,0 +1,44 @@
+package errcode
+
+import (
+	"encoding/json"
+	"net/http"
+)
+
+// ServeJSON attempts to serve the errcode in a JSON envelope. It marshals err
+// and sets the content-type header to 'application/json'. It will handle
+// ErrorCoder and Errors, and if necessary will create an envelope.
+func ServeJSON(w http.ResponseWriter, err error) error {
+	w.Header().Set("Content-Type", "application/json; charset=utf-8")
+	var sc int
+
+	switch errs := err.(type) {
+	case Errors:
+		if len(errs) < 1 {
+			break
+		}
+
+		if err, ok := errs[0].(ErrorCoder); ok {
+			sc = err.ErrorCode().Descriptor().HTTPStatusCode
+		}
+	case ErrorCoder:
+		sc = errs.ErrorCode().Descriptor().HTTPStatusCode
+		err = Errors{err} // create an envelope.
+	default:
+		// We just have an unhandled error type, so just place in an envelope
+		// and move along.
+		err = Errors{err}
+	}
+
+	if sc == 0 {
+		sc = http.StatusInternalServerError
+	}
+
+	w.WriteHeader(sc)
+
+	if err := json.NewEncoder(w).Encode(err); err != nil {
+		return err
+	}
+
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/errcode/register.go b/vendor/github.com/docker/distribution/registry/api/errcode/register.go
new file mode 100644
index 000000000..d1e8826c6
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/errcode/register.go
@@ -0,0 +1,138 @@
+package errcode
+
+import (
+	"fmt"
+	"net/http"
+	"sort"
+	"sync"
+)
+
+var (
+	errorCodeToDescriptors = map[ErrorCode]ErrorDescriptor{}
+	idToDescriptors        = map[string]ErrorDescriptor{}
+	groupToDescriptors     = map[string][]ErrorDescriptor{}
+)
+
+var (
+	// ErrorCodeUnknown is a generic error that can be used as a last
+	// resort if there is no situation-specific error message that can be used
+	ErrorCodeUnknown = Register("errcode", ErrorDescriptor{
+		Value:   "UNKNOWN",
+		Message: "unknown error",
+		Description: `Generic error returned when the error does not have an
+			                                            API classification.`,
+		HTTPStatusCode: http.StatusInternalServerError,
+	})
+
+	// ErrorCodeUnsupported is returned when an operation is not supported.
+	ErrorCodeUnsupported = Register("errcode", ErrorDescriptor{
+		Value:   "UNSUPPORTED",
+		Message: "The operation is unsupported.",
+		Description: `The operation was unsupported due to a missing
+		implementation or invalid set of parameters.`,
+		HTTPStatusCode: http.StatusMethodNotAllowed,
+	})
+
+	// ErrorCodeUnauthorized is returned if a request requires
+	// authentication.
+	ErrorCodeUnauthorized = Register("errcode", ErrorDescriptor{
+		Value:   "UNAUTHORIZED",
+		Message: "authentication required",
+		Description: `The access controller was unable to authenticate
+		the client. Often this will be accompanied by a
+		Www-Authenticate HTTP response header indicating how to
+		authenticate.`,
+		HTTPStatusCode: http.StatusUnauthorized,
+	})
+
+	// ErrorCodeDenied is returned if a client does not have sufficient
+	// permission to perform an action.
+	ErrorCodeDenied = Register("errcode", ErrorDescriptor{
+		Value:   "DENIED",
+		Message: "requested access to the resource is denied",
+		Description: `The access controller denied access for the
+		operation on a resource.`,
+		HTTPStatusCode: http.StatusForbidden,
+	})
+
+	// ErrorCodeUnavailable provides a common error to report unavailability
+	// of a service or endpoint.
+	ErrorCodeUnavailable = Register("errcode", ErrorDescriptor{
+		Value:          "UNAVAILABLE",
+		Message:        "service unavailable",
+		Description:    "Returned when a service is not available",
+		HTTPStatusCode: http.StatusServiceUnavailable,
+	})
+
+	// ErrorCodeTooManyRequests is returned if a client attempts too many
+	// times to contact a service endpoint.
+	ErrorCodeTooManyRequests = Register("errcode", ErrorDescriptor{
+		Value:   "TOOMANYREQUESTS",
+		Message: "too many requests",
+		Description: `Returned when a client attempts to contact a
+		service too many times`,
+		HTTPStatusCode: http.StatusTooManyRequests,
+	})
+)
+
+var nextCode = 1000
+var registerLock sync.Mutex
+
+// Register will make the passed-in error known to the environment and
+// return a new ErrorCode
+func Register(group string, descriptor ErrorDescriptor) ErrorCode {
+	registerLock.Lock()
+	defer registerLock.Unlock()
+
+	descriptor.Code = ErrorCode(nextCode)
+
+	if _, ok := idToDescriptors[descriptor.Value]; ok {
+		panic(fmt.Sprintf("ErrorValue %q is already registered", descriptor.Value))
+	}
+	if _, ok := errorCodeToDescriptors[descriptor.Code]; ok {
+		panic(fmt.Sprintf("ErrorCode %v is already registered", descriptor.Code))
+	}
+
+	groupToDescriptors[group] = append(groupToDescriptors[group], descriptor)
+	errorCodeToDescriptors[descriptor.Code] = descriptor
+	idToDescriptors[descriptor.Value] = descriptor
+
+	nextCode++
+	return descriptor.Code
+}
+
+type byValue []ErrorDescriptor
+
+func (a byValue) Len() int           { return len(a) }
+func (a byValue) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+func (a byValue) Less(i, j int) bool { return a[i].Value < a[j].Value }
+
+// GetGroupNames returns the list of Error group names that are registered
+func GetGroupNames() []string {
+	keys := []string{}
+
+	for k := range groupToDescriptors {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	return keys
+}
+
+// GetErrorCodeGroup returns the named group of error descriptors
+func GetErrorCodeGroup(name string) []ErrorDescriptor {
+	desc := groupToDescriptors[name]
+	sort.Sort(byValue(desc))
+	return desc
+}
+
+// GetErrorAllDescriptors returns a slice of all ErrorDescriptors that are
+// registered, irrespective of what group they're in
+func GetErrorAllDescriptors() []ErrorDescriptor {
+	result := []ErrorDescriptor{}
+
+	for _, group := range GetGroupNames() {
+		result = append(result, GetErrorCodeGroup(group)...)
+	}
+	sort.Sort(byValue(result))
+	return result
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/descriptors.go b/vendor/github.com/docker/distribution/registry/api/v2/descriptors.go
new file mode 100644
index 000000000..a9616c58a
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/descriptors.go
@@ -0,0 +1,1596 @@
+package v2
+
+import (
+	"net/http"
+	"regexp"
+
+	"github.com/docker/distribution/reference"
+	"github.com/docker/distribution/registry/api/errcode"
+	"github.com/opencontainers/go-digest"
+)
+
+var (
+	nameParameterDescriptor = ParameterDescriptor{
+		Name:        "name",
+		Type:        "string",
+		Format:      reference.NameRegexp.String(),
+		Required:    true,
+		Description: `Name of the target repository.`,
+	}
+
+	referenceParameterDescriptor = ParameterDescriptor{
+		Name:        "reference",
+		Type:        "string",
+		Format:      reference.TagRegexp.String(),
+		Required:    true,
+		Description: `Tag or digest of the target manifest.`,
+	}
+
+	uuidParameterDescriptor = ParameterDescriptor{
+		Name:        "uuid",
+		Type:        "opaque",
+		Required:    true,
+		Description: "A uuid identifying the upload. This field can accept characters that match `[a-zA-Z0-9-_.=]+`.",
+	}
+
+	digestPathParameter = ParameterDescriptor{
+		Name:        "digest",
+		Type:        "path",
+		Required:    true,
+		Format:      digest.DigestRegexp.String(),
+		Description: `Digest of desired blob.`,
+	}
+
+	hostHeader = ParameterDescriptor{
+		Name:        "Host",
+		Type:        "string",
+		Description: "Standard HTTP Host Header. Should be set to the registry host.",
+		Format:      "<registry host>",
+		Examples:    []string{"registry-1.docker.io"},
+	}
+
+	authHeader = ParameterDescriptor{
+		Name:        "Authorization",
+		Type:        "string",
+		Description: "An RFC7235 compliant authorization header.",
+		Format:      "<scheme> <token>",
+		Examples:    []string{"Bearer dGhpcyBpcyBhIGZha2UgYmVhcmVyIHRva2VuIQ=="},
+	}
+
+	authChallengeHeader = ParameterDescriptor{
+		Name:        "WWW-Authenticate",
+		Type:        "string",
+		Description: "An RFC7235 compliant authentication challenge header.",
+		Format:      `<scheme> realm="<realm>", ..."`,
+		Examples: []string{
+			`Bearer realm="https://auth.docker.com/", service="registry.docker.com", scopes="repository:library/ubuntu:pull"`,
+		},
+	}
+
+	contentLengthZeroHeader = ParameterDescriptor{
+		Name:        "Content-Length",
+		Description: "The `Content-Length` header must be zero and the body must be empty.",
+		Type:        "integer",
+		Format:      "0",
+	}
+
+	dockerUploadUUIDHeader = ParameterDescriptor{
+		Name:        "Docker-Upload-UUID",
+		Description: "Identifies the docker upload uuid for the current request.",
+		Type:        "uuid",
+		Format:      "<uuid>",
+	}
+
+	digestHeader = ParameterDescriptor{
+		Name:        "Docker-Content-Digest",
+		Description: "Digest of the targeted content for the request.",
+		Type:        "digest",
+		Format:      "<digest>",
+	}
+
+	linkHeader = ParameterDescriptor{
+		Name:        "Link",
+		Type:        "link",
+		Description: "RFC5988 compliant rel='next' with URL to next result set, if available",
+		Format:      `<<url>?n=<last n value>&last=<last entry from response>>; rel="next"`,
+	}
+
+	paginationParameters = []ParameterDescriptor{
+		{
+			Name:        "n",
+			Type:        "integer",
+			Description: "Limit the number of entries in each response. It not present, all entries will be returned.",
+			Format:      "<integer>",
+			Required:    false,
+		},
+		{
+			Name:        "last",
+			Type:        "string",
+			Description: "Result set will include values lexically after last.",
+			Format:      "<integer>",
+			Required:    false,
+		},
+	}
+
+	unauthorizedResponseDescriptor = ResponseDescriptor{
+		Name:        "Authentication Required",
+		StatusCode:  http.StatusUnauthorized,
+		Description: "The client is not authenticated.",
+		Headers: []ParameterDescriptor{
+			authChallengeHeader,
+			{
+				Name:        "Content-Length",
+				Type:        "integer",
+				Description: "Length of the JSON response body.",
+				Format:      "<length>",
+			},
+		},
+		Body: BodyDescriptor{
+			ContentType: "application/json; charset=utf-8",
+			Format:      errorsBody,
+		},
+		ErrorCodes: []errcode.ErrorCode{
+			errcode.ErrorCodeUnauthorized,
+		},
+	}
+
+	repositoryNotFoundResponseDescriptor = ResponseDescriptor{
+		Name:        "No Such Repository Error",
+		StatusCode:  http.StatusNotFound,
+		Description: "The repository is not known to the registry.",
+		Headers: []ParameterDescriptor{
+			{
+				Name:        "Content-Length",
+				Type:        "integer",
+				Description: "Length of the JSON response body.",
+				Format:      "<length>",
+			},
+		},
+		Body: BodyDescriptor{
+			ContentType: "application/json; charset=utf-8",
+			Format:      errorsBody,
+		},
+		ErrorCodes: []errcode.ErrorCode{
+			ErrorCodeNameUnknown,
+		},
+	}
+
+	deniedResponseDescriptor = ResponseDescriptor{
+		Name:        "Access Denied",
+		StatusCode:  http.StatusForbidden,
+		Description: "The client does not have required access to the repository.",
+		Headers: []ParameterDescriptor{
+			{
+				Name:        "Content-Length",
+				Type:        "integer",
+				Description: "Length of the JSON response body.",
+				Format:      "<length>",
+			},
+		},
+		Body: BodyDescriptor{
+			ContentType: "application/json; charset=utf-8",
+			Format:      errorsBody,
+		},
+		ErrorCodes: []errcode.ErrorCode{
+			errcode.ErrorCodeDenied,
+		},
+	}
+
+	tooManyRequestsDescriptor = ResponseDescriptor{
+		Name:        "Too Many Requests",
+		StatusCode:  http.StatusTooManyRequests,
+		Description: "The client made too many requests within a time interval.",
+		Headers: []ParameterDescriptor{
+			{
+				Name:        "Content-Length",
+				Type:        "integer",
+				Description: "Length of the JSON response body.",
+				Format:      "<length>",
+			},
+		},
+		Body: BodyDescriptor{
+			ContentType: "application/json; charset=utf-8",
+			Format:      errorsBody,
+		},
+		ErrorCodes: []errcode.ErrorCode{
+			errcode.ErrorCodeTooManyRequests,
+		},
+	}
+)
+
+const (
+	manifestBody = `{
+   "name": <name>,
+   "tag": <tag>,
+   "fsLayers": [
+      {
+         "blobSum": "<digest>"
+      },
+      ...
+    ]
+   ],
+   "history": <v1 images>,
+   "signature": <JWS>
+}`
+
+	errorsBody = `{
+	"errors:" [
+	    {
+            "code": <error code>,
+            "message": "<error message>",
+            "detail": ...
+        },
+        ...
+    ]
+}`
+)
+
+// APIDescriptor exports descriptions of the layout of the v2 registry API.
+var APIDescriptor = struct {
+	// RouteDescriptors provides a list of the routes available in the API.
+	RouteDescriptors []RouteDescriptor
+}{
+	RouteDescriptors: routeDescriptors,
+}
+
+// RouteDescriptor describes a route specified by name.
+type RouteDescriptor struct {
+	// Name is the name of the route, as specified in RouteNameXXX exports.
+	// These names a should be considered a unique reference for a route. If
+	// the route is registered with gorilla, this is the name that will be
+	// used.
+	Name string
+
+	// Path is a gorilla/mux-compatible regexp that can be used to match the
+	// route. For any incoming method and path, only one route descriptor
+	// should match.
+	Path string
+
+	// Entity should be a short, human-readalbe description of the object
+	// targeted by the endpoint.
+	Entity string
+
+	// Description should provide an accurate overview of the functionality
+	// provided by the route.
+	Description string
+
+	// Methods should describe the various HTTP methods that may be used on
+	// this route, including request and response formats.
+	Methods []MethodDescriptor
+}
+
+// MethodDescriptor provides a description of the requests that may be
+// conducted with the target method.
+type MethodDescriptor struct {
+
+	// Method is an HTTP method, such as GET, PUT or POST.
+	Method string
+
+	// Description should provide an overview of the functionality provided by
+	// the covered method, suitable for use in documentation. Use of markdown
+	// here is encouraged.
+	Description string
+
+	// Requests is a slice of request descriptors enumerating how this
+	// endpoint may be used.
+	Requests []RequestDescriptor
+}
+
+// RequestDescriptor covers a particular set of headers and parameters that
+// can be carried out with the parent method. Its most helpful to have one
+// RequestDescriptor per API use case.
+type RequestDescriptor struct {
+	// Name provides a short identifier for the request, usable as a title or
+	// to provide quick context for the particular request.
+	Name string
+
+	// Description should cover the requests purpose, covering any details for
+	// this particular use case.
+	Description string
+
+	// Headers describes headers that must be used with the HTTP request.
+	Headers []ParameterDescriptor
+
+	// PathParameters enumerate the parameterized path components for the
+	// given request, as defined in the route's regular expression.
+	PathParameters []ParameterDescriptor
+
+	// QueryParameters provides a list of query parameters for the given
+	// request.
+	QueryParameters []ParameterDescriptor
+
+	// Body describes the format of the request body.
+	Body BodyDescriptor
+
+	// Successes enumerates the possible responses that are considered to be
+	// the result of a successful request.
+	Successes []ResponseDescriptor
+
+	// Failures covers the possible failures from this particular request.
+	Failures []ResponseDescriptor
+}
+
+// ResponseDescriptor describes the components of an API response.
+type ResponseDescriptor struct {
+	// Name provides a short identifier for the response, usable as a title or
+	// to provide quick context for the particular response.
+	Name string
+
+	// Description should provide a brief overview of the role of the
+	// response.
+	Description string
+
+	// StatusCode specifies the status received by this particular response.
+	StatusCode int
+
+	// Headers covers any headers that may be returned from the response.
+	Headers []ParameterDescriptor
+
+	// Fields describes any fields that may be present in the response.
+	Fields []ParameterDescriptor
+
+	// ErrorCodes enumerates the error codes that may be returned along with
+	// the response.
+	ErrorCodes []errcode.ErrorCode
+
+	// Body describes the body of the response, if any.
+	Body BodyDescriptor
+}
+
+// BodyDescriptor describes a request body and its expected content type. For
+// the most  part, it should be example json or some placeholder for body
+// data in documentation.
+type BodyDescriptor struct {
+	ContentType string
+	Format      string
+}
+
+// ParameterDescriptor describes the format of a request parameter, which may
+// be a header, path parameter or query parameter.
+type ParameterDescriptor struct {
+	// Name is the name of the parameter, either of the path component or
+	// query parameter.
+	Name string
+
+	// Type specifies the type of the parameter, such as string, integer, etc.
+	Type string
+
+	// Description provides a human-readable description of the parameter.
+	Description string
+
+	// Required means the field is required when set.
+	Required bool
+
+	// Format is a specifying the string format accepted by this parameter.
+	Format string
+
+	// Regexp is a compiled regular expression that can be used to validate
+	// the contents of the parameter.
+	Regexp *regexp.Regexp
+
+	// Examples provides multiple examples for the values that might be valid
+	// for this parameter.
+	Examples []string
+}
+
+var routeDescriptors = []RouteDescriptor{
+	{
+		Name:        RouteNameBase,
+		Path:        "/v2/",
+		Entity:      "Base",
+		Description: `Base V2 API route. Typically, this can be used for lightweight version checks and to validate registry authentication.`,
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Check that the endpoint implements Docker Registry API V2.",
+				Requests: []RequestDescriptor{
+					{
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The API implements V2 protocol and is accessible.",
+								StatusCode:  http.StatusOK,
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "The registry does not implement the V2 API.",
+								StatusCode:  http.StatusNotFound,
+							},
+							unauthorizedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+		},
+	},
+	{
+		Name:        RouteNameTags,
+		Path:        "/v2/{name:" + reference.NameRegexp.String() + "}/tags/list",
+		Entity:      "Tags",
+		Description: "Retrieve information about tags.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Fetch the tags under the repository identified by `name`.",
+				Requests: []RequestDescriptor{
+					{
+						Name:        "Tags",
+						Description: "Return all tags for the repository",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								StatusCode:  http.StatusOK,
+								Description: "A list of tags for the named repository.",
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "Length of the JSON response body.",
+										Format:      "<length>",
+									},
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format: `{
+    "name": <name>,
+    "tags": [
+        <tag>,
+        ...
+    ]
+}`,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+					{
+						Name:            "Tags Paginated",
+						Description:     "Return a portion of the tags for the specified repository.",
+						PathParameters:  []ParameterDescriptor{nameParameterDescriptor},
+						QueryParameters: paginationParameters,
+						Successes: []ResponseDescriptor{
+							{
+								StatusCode:  http.StatusOK,
+								Description: "A list of tags for the named repository.",
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "Length of the JSON response body.",
+										Format:      "<length>",
+									},
+									linkHeader,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format: `{
+    "name": <name>,
+    "tags": [
+        <tag>,
+        ...
+    ],
+}`,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+		},
+	},
+	{
+		Name:        RouteNameManifest,
+		Path:        "/v2/{name:" + reference.NameRegexp.String() + "}/manifests/{reference:" + reference.TagRegexp.String() + "|" + digest.DigestRegexp.String() + "}",
+		Entity:      "Manifest",
+		Description: "Create, update, delete and retrieve manifests.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Fetch the manifest identified by `name` and `reference` where `reference` can be a tag or digest. A `HEAD` request can also be issued to this endpoint to obtain resource information without receiving all data.",
+				Requests: []RequestDescriptor{
+					{
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							referenceParameterDescriptor,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The manifest identified by `name` and `reference`. The contents can be used to identify and resolve resources required to run the specified image.",
+								StatusCode:  http.StatusOK,
+								Headers: []ParameterDescriptor{
+									digestHeader,
+								},
+								Body: BodyDescriptor{
+									ContentType: "<media type of manifest>",
+									Format:      manifestBody,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "The name or reference was invalid.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeTagInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+			{
+				Method:      "PUT",
+				Description: "Put the manifest identified by `name` and `reference` where `reference` can be a tag or digest.",
+				Requests: []RequestDescriptor{
+					{
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							referenceParameterDescriptor,
+						},
+						Body: BodyDescriptor{
+							ContentType: "<media type of manifest>",
+							Format:      manifestBody,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The manifest has been accepted by the registry and is stored under the specified `name` and `tag`.",
+								StatusCode:  http.StatusCreated,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Location",
+										Type:        "url",
+										Description: "The canonical location url of the uploaded manifest.",
+										Format:      "<url>",
+									},
+									contentLengthZeroHeader,
+									digestHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:        "Invalid Manifest",
+								Description: "The received manifest was invalid in some way, as described by the error codes. The client should resolve the issue and retry the request.",
+								StatusCode:  http.StatusBadRequest,
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeTagInvalid,
+									ErrorCodeManifestInvalid,
+									ErrorCodeManifestUnverified,
+									ErrorCodeBlobUnknown,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+							{
+								Name:        "Missing Layer(s)",
+								Description: "One or more layers may be missing during a manifest upload. If so, the missing layers will be enumerated in the error response.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format: `{
+    "errors:" [{
+            "code": "BLOB_UNKNOWN",
+            "message": "blob unknown to registry",
+            "detail": {
+                "digest": "<digest>"
+            }
+        },
+        ...
+    ]
+}`,
+								},
+							},
+							{
+								Name:        "Not allowed",
+								Description: "Manifest put is not allowed because the registry is configured as a pull-through cache or for some other reason",
+								StatusCode:  http.StatusMethodNotAllowed,
+								ErrorCodes: []errcode.ErrorCode{
+									errcode.ErrorCodeUnsupported,
+								},
+							},
+						},
+					},
+				},
+			},
+			{
+				Method:      "DELETE",
+				Description: "Delete the manifest identified by `name` and `reference`. Note that a manifest can _only_ be deleted by `digest`.",
+				Requests: []RequestDescriptor{
+					{
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							referenceParameterDescriptor,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								StatusCode: http.StatusAccepted,
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:        "Invalid Name or Reference",
+								Description: "The specified `name` or `reference` were invalid and the delete was unable to proceed.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeTagInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+							{
+								Name:        "Unknown Manifest",
+								Description: "The specified `name` or `reference` are unknown to the registry and the delete was unable to proceed. Clients can assume the manifest was already deleted if this response is returned.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameUnknown,
+									ErrorCodeManifestUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Name:        "Not allowed",
+								Description: "Manifest delete is not allowed because the registry is configured as a pull-through cache or `delete` has been disabled.",
+								StatusCode:  http.StatusMethodNotAllowed,
+								ErrorCodes: []errcode.ErrorCode{
+									errcode.ErrorCodeUnsupported,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	},
+
+	{
+		Name:        RouteNameBlob,
+		Path:        "/v2/{name:" + reference.NameRegexp.String() + "}/blobs/{digest:" + digest.DigestRegexp.String() + "}",
+		Entity:      "Blob",
+		Description: "Operations on blobs identified by `name` and `digest`. Used to fetch or delete layers by digest.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Retrieve the blob from the registry identified by `digest`. A `HEAD` request can also be issued to this endpoint to obtain resource information without receiving all data.",
+				Requests: []RequestDescriptor{
+					{
+						Name: "Fetch Blob",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							digestPathParameter,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The blob identified by `digest` is available. The blob content will be present in the body of the request.",
+								StatusCode:  http.StatusOK,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "The length of the requested blob content.",
+										Format:      "<length>",
+									},
+									digestHeader,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/octet-stream",
+									Format:      "<blob binary data>",
+								},
+							},
+							{
+								Description: "The blob identified by `digest` is available at the provided location.",
+								StatusCode:  http.StatusTemporaryRedirect,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Location",
+										Type:        "url",
+										Description: "The location where the layer should be accessible.",
+										Format:      "<blob location>",
+									},
+									digestHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was a problem with the request that needs to be addressed by the client, such as an invalid `name` or `tag`.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeDigestInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The blob, identified by `name` and `digest`, is unknown to the registry.",
+								StatusCode:  http.StatusNotFound,
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameUnknown,
+									ErrorCodeBlobUnknown,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+					{
+						Name:        "Fetch Blob Part",
+						Description: "This endpoint may also support RFC7233 compliant range requests. Support can be detected by issuing a HEAD request. If the header `Accept-Range: bytes` is returned, range requests can be used to fetch partial content.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							{
+								Name:        "Range",
+								Type:        "string",
+								Description: "HTTP Range header specifying blob chunk.",
+								Format:      "bytes=<start>-<end>",
+							},
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							digestPathParameter,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The blob identified by `digest` is available. The specified chunk of blob content will be present in the body of the request.",
+								StatusCode:  http.StatusPartialContent,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "The length of the requested blob chunk.",
+										Format:      "<length>",
+									},
+									{
+										Name:        "Content-Range",
+										Type:        "byte range",
+										Description: "Content range of blob chunk.",
+										Format:      "bytes <start>-<end>/<size>",
+									},
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/octet-stream",
+									Format:      "<blob binary data>",
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was a problem with the request that needs to be addressed by the client, such as an invalid `name` or `tag`.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeDigestInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								StatusCode: http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameUnknown,
+									ErrorCodeBlobUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The range specification cannot be satisfied for the requested content. This can happen when the range is not formatted correctly or if the range is outside of the valid size of the content.",
+								StatusCode:  http.StatusRequestedRangeNotSatisfiable,
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+			{
+				Method:      "DELETE",
+				Description: "Delete the blob identified by `name` and `digest`",
+				Requests: []RequestDescriptor{
+					{
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							digestPathParameter,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								StatusCode: http.StatusAccepted,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "0",
+										Format:      "0",
+									},
+									digestHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:       "Invalid Name or Digest",
+								StatusCode: http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+								},
+							},
+							{
+								Description: "The blob, identified by `name` and `digest`, is unknown to the registry.",
+								StatusCode:  http.StatusNotFound,
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameUnknown,
+									ErrorCodeBlobUnknown,
+								},
+							},
+							{
+								Description: "Blob delete is not allowed because the registry is configured as a pull-through cache or `delete` has been disabled",
+								StatusCode:  http.StatusMethodNotAllowed,
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+								ErrorCodes: []errcode.ErrorCode{
+									errcode.ErrorCodeUnsupported,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+
+			// TODO(stevvooe): We may want to add a PUT request here to
+			// kickoff an upload of a blob, integrated with the blob upload
+			// API.
+		},
+	},
+
+	{
+		Name:        RouteNameBlobUpload,
+		Path:        "/v2/{name:" + reference.NameRegexp.String() + "}/blobs/uploads/",
+		Entity:      "Initiate Blob Upload",
+		Description: "Initiate a blob upload. This endpoint can be used to create resumable uploads or monolithic uploads.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "POST",
+				Description: "Initiate a resumable blob upload. If successful, an upload location will be provided to complete the upload. Optionally, if the `digest` parameter is present, the request body will be used to complete the upload in a single request.",
+				Requests: []RequestDescriptor{
+					{
+						Name:        "Initiate Monolithic Blob Upload",
+						Description: "Upload a blob identified by the `digest` parameter in single request. This upload will not be resumable unless a recoverable error is returned.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							{
+								Name:   "Content-Length",
+								Type:   "integer",
+								Format: "<length of blob>",
+							},
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+						},
+						QueryParameters: []ParameterDescriptor{
+							{
+								Name:        "digest",
+								Type:        "query",
+								Format:      "<digest>",
+								Regexp:      digest.DigestRegexp,
+								Description: `Digest of uploaded blob. If present, the upload will be completed, in a single request, with contents of the request body as the resulting blob.`,
+							},
+						},
+						Body: BodyDescriptor{
+							ContentType: "application/octect-stream",
+							Format:      "<binary data>",
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The blob has been created in the registry and is available at the provided location.",
+								StatusCode:  http.StatusCreated,
+								Headers: []ParameterDescriptor{
+									{
+										Name:   "Location",
+										Type:   "url",
+										Format: "<blob location>",
+									},
+									contentLengthZeroHeader,
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:       "Invalid Name or Digest",
+								StatusCode: http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+								},
+							},
+							{
+								Name:        "Not allowed",
+								Description: "Blob upload is not allowed because the registry is configured as a pull-through cache or for some other reason",
+								StatusCode:  http.StatusMethodNotAllowed,
+								ErrorCodes: []errcode.ErrorCode{
+									errcode.ErrorCodeUnsupported,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+					{
+						Name:        "Initiate Resumable Blob Upload",
+						Description: "Initiate a resumable blob upload with an empty request body.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							contentLengthZeroHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The upload has been created. The `Location` header must be used to complete the upload. The response should be identical to a `GET` request on the contents of the returned `Location` header.",
+								StatusCode:  http.StatusAccepted,
+								Headers: []ParameterDescriptor{
+									contentLengthZeroHeader,
+									{
+										Name:        "Location",
+										Type:        "url",
+										Format:      "/v2/<name>/blobs/uploads/<uuid>",
+										Description: "The location of the created upload. Clients should use the contents verbatim to complete the upload, adding parameters where required.",
+									},
+									{
+										Name:        "Range",
+										Format:      "0-0",
+										Description: "Range header indicating the progress of the upload. When starting an upload, it will return an empty range, since no content has been received.",
+									},
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:       "Invalid Name or Digest",
+								StatusCode: http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+					{
+						Name:        "Mount Blob",
+						Description: "Mount a blob identified by the `mount` parameter from another repository.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							contentLengthZeroHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+						},
+						QueryParameters: []ParameterDescriptor{
+							{
+								Name:        "mount",
+								Type:        "query",
+								Format:      "<digest>",
+								Regexp:      digest.DigestRegexp,
+								Description: `Digest of blob to mount from the source repository.`,
+							},
+							{
+								Name:        "from",
+								Type:        "query",
+								Format:      "<repository name>",
+								Regexp:      reference.NameRegexp,
+								Description: `Name of the source repository.`,
+							},
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Description: "The blob has been mounted in the repository and is available at the provided location.",
+								StatusCode:  http.StatusCreated,
+								Headers: []ParameterDescriptor{
+									{
+										Name:   "Location",
+										Type:   "url",
+										Format: "<blob location>",
+									},
+									contentLengthZeroHeader,
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Name:       "Invalid Name or Digest",
+								StatusCode: http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+								},
+							},
+							{
+								Name:        "Not allowed",
+								Description: "Blob mount is not allowed because the registry is configured as a pull-through cache or for some other reason",
+								StatusCode:  http.StatusMethodNotAllowed,
+								ErrorCodes: []errcode.ErrorCode{
+									errcode.ErrorCodeUnsupported,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+		},
+	},
+
+	{
+		Name:        RouteNameBlobUploadChunk,
+		Path:        "/v2/{name:" + reference.NameRegexp.String() + "}/blobs/uploads/{uuid:[a-zA-Z0-9-_.=]+}",
+		Entity:      "Blob Upload",
+		Description: "Interact with blob uploads. Clients should never assemble URLs for this endpoint and should only take it through the `Location` header on related API requests. The `Location` header and its parameters should be preserved by clients, using the latest value returned via upload related API calls.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Retrieve status of upload identified by `uuid`. The primary purpose of this endpoint is to resolve the current status of a resumable upload.",
+				Requests: []RequestDescriptor{
+					{
+						Description: "Retrieve the progress of the current upload, as reported by the `Range` header.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							uuidParameterDescriptor,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Name:        "Upload Progress",
+								Description: "The upload is known and in progress. The last received offset is available in the `Range` header.",
+								StatusCode:  http.StatusNoContent,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Range",
+										Type:        "header",
+										Format:      "0-<offset>",
+										Description: "Range indicating the current progress of the upload.",
+									},
+									contentLengthZeroHeader,
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was an error processing the upload and it must be restarted.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+									ErrorCodeBlobUploadInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The upload is unknown to the registry. The upload must be restarted.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUploadUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+			{
+				Method:      "PATCH",
+				Description: "Upload a chunk of data for the specified upload.",
+				Requests: []RequestDescriptor{
+					{
+						Name:        "Stream upload",
+						Description: "Upload a stream of data to upload without completing the upload.",
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							uuidParameterDescriptor,
+						},
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+						},
+						Body: BodyDescriptor{
+							ContentType: "application/octet-stream",
+							Format:      "<binary data>",
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Name:        "Data Accepted",
+								Description: "The stream of data has been accepted and the current progress is available in the range header. The updated upload location is available in the `Location` header.",
+								StatusCode:  http.StatusNoContent,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Location",
+										Type:        "url",
+										Format:      "/v2/<name>/blobs/uploads/<uuid>",
+										Description: "The location of the upload. Clients should assume this changes after each request. Clients should use the contents verbatim to complete the upload, adding parameters where required.",
+									},
+									{
+										Name:        "Range",
+										Type:        "header",
+										Format:      "0-<offset>",
+										Description: "Range indicating the current progress of the upload.",
+									},
+									contentLengthZeroHeader,
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was an error processing the upload and it must be restarted.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+									ErrorCodeBlobUploadInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The upload is unknown to the registry. The upload must be restarted.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUploadUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+					{
+						Name:        "Chunked upload",
+						Description: "Upload a chunk of data to specified upload without completing the upload. The data will be uploaded to the specified Content Range.",
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							uuidParameterDescriptor,
+						},
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							{
+								Name:        "Content-Range",
+								Type:        "header",
+								Format:      "<start of range>-<end of range, inclusive>",
+								Required:    true,
+								Description: "Range of bytes identifying the desired block of content represented by the body. Start must the end offset retrieved via status check plus one. Note that this is a non-standard use of the `Content-Range` header.",
+							},
+							{
+								Name:        "Content-Length",
+								Type:        "integer",
+								Format:      "<length of chunk>",
+								Description: "Length of the chunk being uploaded, corresponding the length of the request body.",
+							},
+						},
+						Body: BodyDescriptor{
+							ContentType: "application/octet-stream",
+							Format:      "<binary chunk>",
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Name:        "Chunk Accepted",
+								Description: "The chunk of data has been accepted and the current progress is available in the range header. The updated upload location is available in the `Location` header.",
+								StatusCode:  http.StatusNoContent,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Location",
+										Type:        "url",
+										Format:      "/v2/<name>/blobs/uploads/<uuid>",
+										Description: "The location of the upload. Clients should assume this changes after each request. Clients should use the contents verbatim to complete the upload, adding parameters where required.",
+									},
+									{
+										Name:        "Range",
+										Type:        "header",
+										Format:      "0-<offset>",
+										Description: "Range indicating the current progress of the upload.",
+									},
+									contentLengthZeroHeader,
+									dockerUploadUUIDHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was an error processing the upload and it must be restarted.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+									ErrorCodeBlobUploadInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The upload is unknown to the registry. The upload must be restarted.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUploadUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The `Content-Range` specification cannot be accepted, either because it does not overlap with the current progress or it is invalid.",
+								StatusCode:  http.StatusRequestedRangeNotSatisfiable,
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+			{
+				Method:      "PUT",
+				Description: "Complete the upload specified by `uuid`, optionally appending the body as the final chunk.",
+				Requests: []RequestDescriptor{
+					{
+						Description: "Complete the upload, providing all the data in the body, if necessary. A request without a body will just complete the upload with previously uploaded content.",
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							{
+								Name:        "Content-Length",
+								Type:        "integer",
+								Format:      "<length of data>",
+								Description: "Length of the data being uploaded, corresponding to the length of the request body. May be zero if no data is provided.",
+							},
+						},
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							uuidParameterDescriptor,
+						},
+						QueryParameters: []ParameterDescriptor{
+							{
+								Name:        "digest",
+								Type:        "string",
+								Format:      "<digest>",
+								Regexp:      digest.DigestRegexp,
+								Required:    true,
+								Description: `Digest of uploaded blob.`,
+							},
+						},
+						Body: BodyDescriptor{
+							ContentType: "application/octet-stream",
+							Format:      "<binary data>",
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Name:        "Upload Complete",
+								Description: "The upload has been completed and accepted by the registry. The canonical location will be available in the `Location` header.",
+								StatusCode:  http.StatusNoContent,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Location",
+										Type:        "url",
+										Format:      "<blob location>",
+										Description: "The canonical location of the blob for retrieval",
+									},
+									{
+										Name:        "Content-Range",
+										Type:        "header",
+										Format:      "<start of range>-<end of range, inclusive>",
+										Description: "Range of bytes identifying the desired block of content represented by the body. Start must match the end of offset retrieved via status check. Note that this is a non-standard use of the `Content-Range` header.",
+									},
+									contentLengthZeroHeader,
+									digestHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "There was an error processing the upload and it must be restarted.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeDigestInvalid,
+									ErrorCodeNameInvalid,
+									ErrorCodeBlobUploadInvalid,
+									errcode.ErrorCodeUnsupported,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The upload is unknown to the registry. The upload must be restarted.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUploadUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+			{
+				Method:      "DELETE",
+				Description: "Cancel outstanding upload processes, releasing associated resources. If this is not called, the unfinished uploads will eventually timeout.",
+				Requests: []RequestDescriptor{
+					{
+						Description: "Cancel the upload specified by `uuid`.",
+						PathParameters: []ParameterDescriptor{
+							nameParameterDescriptor,
+							uuidParameterDescriptor,
+						},
+						Headers: []ParameterDescriptor{
+							hostHeader,
+							authHeader,
+							contentLengthZeroHeader,
+						},
+						Successes: []ResponseDescriptor{
+							{
+								Name:        "Upload Deleted",
+								Description: "The upload has been successfully deleted.",
+								StatusCode:  http.StatusNoContent,
+								Headers: []ParameterDescriptor{
+									contentLengthZeroHeader,
+								},
+							},
+						},
+						Failures: []ResponseDescriptor{
+							{
+								Description: "An error was encountered processing the delete. The client may ignore this error.",
+								StatusCode:  http.StatusBadRequest,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeNameInvalid,
+									ErrorCodeBlobUploadInvalid,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							{
+								Description: "The upload is unknown to the registry. The client may ignore this error and assume the upload has been deleted.",
+								StatusCode:  http.StatusNotFound,
+								ErrorCodes: []errcode.ErrorCode{
+									ErrorCodeBlobUploadUnknown,
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format:      errorsBody,
+								},
+							},
+							unauthorizedResponseDescriptor,
+							repositoryNotFoundResponseDescriptor,
+							deniedResponseDescriptor,
+							tooManyRequestsDescriptor,
+						},
+					},
+				},
+			},
+		},
+	},
+	{
+		Name:        RouteNameCatalog,
+		Path:        "/v2/_catalog",
+		Entity:      "Catalog",
+		Description: "List a set of available repositories in the local registry cluster. Does not provide any indication of what may be available upstream. Applications can only determine if a repository is available but not if it is not available.",
+		Methods: []MethodDescriptor{
+			{
+				Method:      "GET",
+				Description: "Retrieve a sorted, json list of repositories available in the registry.",
+				Requests: []RequestDescriptor{
+					{
+						Name:        "Catalog Fetch",
+						Description: "Request an unabridged list of repositories available.  The implementation may impose a maximum limit and return a partial set with pagination links.",
+						Successes: []ResponseDescriptor{
+							{
+								Description: "Returns the unabridged list of repositories as a json response.",
+								StatusCode:  http.StatusOK,
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "Length of the JSON response body.",
+										Format:      "<length>",
+									},
+								},
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format: `{
+	"repositories": [
+		<name>,
+		...
+	]
+}`,
+								},
+							},
+						},
+					},
+					{
+						Name:            "Catalog Fetch Paginated",
+						Description:     "Return the specified portion of repositories.",
+						QueryParameters: paginationParameters,
+						Successes: []ResponseDescriptor{
+							{
+								StatusCode: http.StatusOK,
+								Body: BodyDescriptor{
+									ContentType: "application/json; charset=utf-8",
+									Format: `{
+	"repositories": [
+		<name>,
+		...
+	]
+	"next": "<url>?last=<name>&n=<last value of n>"
+}`,
+								},
+								Headers: []ParameterDescriptor{
+									{
+										Name:        "Content-Length",
+										Type:        "integer",
+										Description: "Length of the JSON response body.",
+										Format:      "<length>",
+									},
+									linkHeader,
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	},
+}
+
+var routeDescriptorsMap map[string]RouteDescriptor
+
+func init() {
+	routeDescriptorsMap = make(map[string]RouteDescriptor, len(routeDescriptors))
+
+	for _, descriptor := range routeDescriptors {
+		routeDescriptorsMap[descriptor.Name] = descriptor
+	}
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/doc.go b/vendor/github.com/docker/distribution/registry/api/v2/doc.go
new file mode 100644
index 000000000..cde011959
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/doc.go
@@ -0,0 +1,9 @@
+// Package v2 describes routes, urls and the error codes used in the Docker
+// Registry JSON HTTP API V2. In addition to declarations, descriptors are
+// provided for routes and error codes that can be used for implementation and
+// automatically generating documentation.
+//
+// Definitions here are considered to be locked down for the V2 registry api.
+// Any changes must be considered carefully and should not proceed without a
+// change proposal in docker core.
+package v2
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/errors.go b/vendor/github.com/docker/distribution/registry/api/v2/errors.go
new file mode 100644
index 000000000..97d6923aa
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/errors.go
@@ -0,0 +1,136 @@
+package v2
+
+import (
+	"net/http"
+
+	"github.com/docker/distribution/registry/api/errcode"
+)
+
+const errGroup = "registry.api.v2"
+
+var (
+	// ErrorCodeDigestInvalid is returned when uploading a blob if the
+	// provided digest does not match the blob contents.
+	ErrorCodeDigestInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "DIGEST_INVALID",
+		Message: "provided digest did not match uploaded content",
+		Description: `When a blob is uploaded, the registry will check that
+		the content matches the digest provided by the client. The error may
+		include a detail structure with the key "digest", including the
+		invalid digest string. This error may also be returned when a manifest
+		includes an invalid layer digest.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeSizeInvalid is returned when uploading a blob if the provided
+	ErrorCodeSizeInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "SIZE_INVALID",
+		Message: "provided length did not match content length",
+		Description: `When a layer is uploaded, the provided size will be
+		checked against the uploaded content. If they do not match, this error
+		will be returned.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeNameInvalid is returned when the name in the manifest does not
+	// match the provided name.
+	ErrorCodeNameInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "NAME_INVALID",
+		Message: "invalid repository name",
+		Description: `Invalid repository name encountered either during
+		manifest validation or any API operation.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeTagInvalid is returned when the tag in the manifest does not
+	// match the provided tag.
+	ErrorCodeTagInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "TAG_INVALID",
+		Message: "manifest tag did not match URI",
+		Description: `During a manifest upload, if the tag in the manifest
+		does not match the uri tag, this error will be returned.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeNameUnknown when the repository name is not known.
+	ErrorCodeNameUnknown = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "NAME_UNKNOWN",
+		Message: "repository name not known to registry",
+		Description: `This is returned if the name used during an operation is
+		unknown to the registry.`,
+		HTTPStatusCode: http.StatusNotFound,
+	})
+
+	// ErrorCodeManifestUnknown returned when image manifest is unknown.
+	ErrorCodeManifestUnknown = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "MANIFEST_UNKNOWN",
+		Message: "manifest unknown",
+		Description: `This error is returned when the manifest, identified by
+		name and tag is unknown to the repository.`,
+		HTTPStatusCode: http.StatusNotFound,
+	})
+
+	// ErrorCodeManifestInvalid returned when an image manifest is invalid,
+	// typically during a PUT operation. This error encompasses all errors
+	// encountered during manifest validation that aren't signature errors.
+	ErrorCodeManifestInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "MANIFEST_INVALID",
+		Message: "manifest invalid",
+		Description: `During upload, manifests undergo several checks ensuring
+		validity. If those checks fail, this error may be returned, unless a
+		more specific error is included. The detail will contain information
+		the failed validation.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeManifestUnverified is returned when the manifest fails
+	// signature verification.
+	ErrorCodeManifestUnverified = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "MANIFEST_UNVERIFIED",
+		Message: "manifest failed signature verification",
+		Description: `During manifest upload, if the manifest fails signature
+		verification, this error will be returned.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeManifestBlobUnknown is returned when a manifest blob is
+	// unknown to the registry.
+	ErrorCodeManifestBlobUnknown = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "MANIFEST_BLOB_UNKNOWN",
+		Message: "blob unknown to registry",
+		Description: `This error may be returned when a manifest blob is 
+		unknown to the registry.`,
+		HTTPStatusCode: http.StatusBadRequest,
+	})
+
+	// ErrorCodeBlobUnknown is returned when a blob is unknown to the
+	// registry. This can happen when the manifest references a nonexistent
+	// layer or the result is not found by a blob fetch.
+	ErrorCodeBlobUnknown = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "BLOB_UNKNOWN",
+		Message: "blob unknown to registry",
+		Description: `This error may be returned when a blob is unknown to the
+		registry in a specified repository. This can be returned with a
+		standard get or if a manifest references an unknown layer during
+		upload.`,
+		HTTPStatusCode: http.StatusNotFound,
+	})
+
+	// ErrorCodeBlobUploadUnknown is returned when an upload is unknown.
+	ErrorCodeBlobUploadUnknown = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "BLOB_UPLOAD_UNKNOWN",
+		Message: "blob upload unknown to registry",
+		Description: `If a blob upload has been cancelled or was never
+		started, this error code may be returned.`,
+		HTTPStatusCode: http.StatusNotFound,
+	})
+
+	// ErrorCodeBlobUploadInvalid is returned when an upload is invalid.
+	ErrorCodeBlobUploadInvalid = errcode.Register(errGroup, errcode.ErrorDescriptor{
+		Value:   "BLOB_UPLOAD_INVALID",
+		Message: "blob upload invalid",
+		Description: `The blob upload encountered an error and can no
+		longer proceed.`,
+		HTTPStatusCode: http.StatusNotFound,
+	})
+)
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/headerparser.go b/vendor/github.com/docker/distribution/registry/api/v2/headerparser.go
new file mode 100644
index 000000000..9bc41a3a6
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/headerparser.go
@@ -0,0 +1,161 @@
+package v2
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"unicode"
+)
+
+var (
+	// according to rfc7230
+	reToken            = regexp.MustCompile(`^[^"(),/:;<=>?@[\]{}[:space:][:cntrl:]]+`)
+	reQuotedValue      = regexp.MustCompile(`^[^\\"]+`)
+	reEscapedCharacter = regexp.MustCompile(`^[[:blank:][:graph:]]`)
+)
+
+// parseForwardedHeader is a benevolent parser of Forwarded header defined in rfc7239. The header contains
+// a comma-separated list of forwarding key-value pairs. Each list element is set by single proxy. The
+// function parses only the first element of the list, which is set by the very first proxy. It returns a map
+// of corresponding key-value pairs and an unparsed slice of the input string.
+//
+// Examples of Forwarded header values:
+//
+//  1. Forwarded: For=192.0.2.43; Proto=https,For="[2001:db8:cafe::17]",For=unknown
+//  2. Forwarded: for="192.0.2.43:443"; host="registry.example.org", for="10.10.05.40:80"
+//
+// The first will be parsed into {"for": "192.0.2.43", "proto": "https"} while the second into
+// {"for": "192.0.2.43:443", "host": "registry.example.org"}.
+func parseForwardedHeader(forwarded string) (map[string]string, string, error) {
+	// Following are states of forwarded header parser. Any state could transition to a failure.
+	const (
+		// terminating state; can transition to Parameter
+		stateElement = iota
+		// terminating state; can transition to KeyValueDelimiter
+		stateParameter
+		// can transition to Value
+		stateKeyValueDelimiter
+		// can transition to one of { QuotedValue, PairEnd }
+		stateValue
+		// can transition to one of { EscapedCharacter, PairEnd }
+		stateQuotedValue
+		// can transition to one of { QuotedValue }
+		stateEscapedCharacter
+		// terminating state; can transition to one of { Parameter, Element }
+		statePairEnd
+	)
+
+	var (
+		parameter string
+		value     string
+		parse     = forwarded[:]
+		res       = map[string]string{}
+		state     = stateElement
+	)
+
+Loop:
+	for {
+		// skip spaces unless in quoted value
+		if state != stateQuotedValue && state != stateEscapedCharacter {
+			parse = strings.TrimLeftFunc(parse, unicode.IsSpace)
+		}
+
+		if len(parse) == 0 {
+			if state != stateElement && state != statePairEnd && state != stateParameter {
+				return nil, parse, fmt.Errorf("unexpected end of input")
+			}
+			// terminating
+			break
+		}
+
+		switch state {
+		// terminate at list element delimiter
+		case stateElement:
+			if parse[0] == ',' {
+				parse = parse[1:]
+				break Loop
+			}
+			state = stateParameter
+
+		// parse parameter (the key of key-value pair)
+		case stateParameter:
+			match := reToken.FindString(parse)
+			if len(match) == 0 {
+				return nil, parse, fmt.Errorf("failed to parse token at position %d", len(forwarded)-len(parse))
+			}
+			parameter = strings.ToLower(match)
+			parse = parse[len(match):]
+			state = stateKeyValueDelimiter
+
+		// parse '='
+		case stateKeyValueDelimiter:
+			if parse[0] != '=' {
+				return nil, parse, fmt.Errorf("expected '=', not '%c' at position %d", parse[0], len(forwarded)-len(parse))
+			}
+			parse = parse[1:]
+			state = stateValue
+
+		// parse value or quoted value
+		case stateValue:
+			if parse[0] == '"' {
+				parse = parse[1:]
+				state = stateQuotedValue
+			} else {
+				value = reToken.FindString(parse)
+				if len(value) == 0 {
+					return nil, parse, fmt.Errorf("failed to parse value at position %d", len(forwarded)-len(parse))
+				}
+				if _, exists := res[parameter]; exists {
+					return nil, parse, fmt.Errorf("duplicate parameter %q at position %d", parameter, len(forwarded)-len(parse))
+				}
+				res[parameter] = value
+				parse = parse[len(value):]
+				value = ""
+				state = statePairEnd
+			}
+
+		// parse a part of quoted value until the first backslash
+		case stateQuotedValue:
+			match := reQuotedValue.FindString(parse)
+			value += match
+			parse = parse[len(match):]
+			switch {
+			case len(parse) == 0:
+				return nil, parse, fmt.Errorf("unterminated quoted string")
+			case parse[0] == '"':
+				res[parameter] = value
+				value = ""
+				parse = parse[1:]
+				state = statePairEnd
+			case parse[0] == '\\':
+				parse = parse[1:]
+				state = stateEscapedCharacter
+			}
+
+		// parse escaped character in a quoted string, ignore the backslash
+		// transition back to QuotedValue state
+		case stateEscapedCharacter:
+			c := reEscapedCharacter.FindString(parse)
+			if len(c) == 0 {
+				return nil, parse, fmt.Errorf("invalid escape sequence at position %d", len(forwarded)-len(parse)-1)
+			}
+			value += c
+			parse = parse[1:]
+			state = stateQuotedValue
+
+		// expect either a new key-value pair, new list or end of input
+		case statePairEnd:
+			switch parse[0] {
+			case ';':
+				parse = parse[1:]
+				state = stateParameter
+			case ',':
+				state = stateElement
+			default:
+				return nil, parse, fmt.Errorf("expected ',' or ';', not %c at position %d", parse[0], len(forwarded)-len(parse))
+			}
+		}
+	}
+
+	return res, parse, nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/routes.go b/vendor/github.com/docker/distribution/registry/api/v2/routes.go
new file mode 100644
index 000000000..5b80d5be7
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/routes.go
@@ -0,0 +1,49 @@
+package v2
+
+import "github.com/gorilla/mux"
+
+// The following are definitions of the name under which all V2 routes are
+// registered. These symbols can be used to look up a route based on the name.
+const (
+	RouteNameBase            = "base"
+	RouteNameManifest        = "manifest"
+	RouteNameTags            = "tags"
+	RouteNameBlob            = "blob"
+	RouteNameBlobUpload      = "blob-upload"
+	RouteNameBlobUploadChunk = "blob-upload-chunk"
+	RouteNameCatalog         = "catalog"
+)
+
+var allEndpoints = []string{
+	RouteNameManifest,
+	RouteNameCatalog,
+	RouteNameTags,
+	RouteNameBlob,
+	RouteNameBlobUpload,
+	RouteNameBlobUploadChunk,
+}
+
+// Router builds a gorilla router with named routes for the various API
+// methods. This can be used directly by both server implementations and
+// clients.
+func Router() *mux.Router {
+	return RouterWithPrefix("")
+}
+
+// RouterWithPrefix builds a gorilla router with a configured prefix
+// on all routes.
+func RouterWithPrefix(prefix string) *mux.Router {
+	rootRouter := mux.NewRouter()
+	router := rootRouter
+	if prefix != "" {
+		router = router.PathPrefix(prefix).Subrouter()
+	}
+
+	router.StrictSlash(true)
+
+	for _, descriptor := range routeDescriptors {
+		router.Path(descriptor.Path).Name(descriptor.Name)
+	}
+
+	return rootRouter
+}
diff --git a/vendor/github.com/docker/distribution/registry/api/v2/urls.go b/vendor/github.com/docker/distribution/registry/api/v2/urls.go
new file mode 100644
index 000000000..1337bdb12
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/api/v2/urls.go
@@ -0,0 +1,266 @@
+package v2
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/docker/distribution/reference"
+	"github.com/gorilla/mux"
+)
+
+// URLBuilder creates registry API urls from a single base endpoint. It can be
+// used to create urls for use in a registry client or server.
+//
+// All urls will be created from the given base, including the api version.
+// For example, if a root of "/foo/" is provided, urls generated will be fall
+// under "/foo/v2/...". Most application will only provide a schema, host and
+// port, such as "https://localhost:5000/".
+type URLBuilder struct {
+	root     *url.URL // url root (ie http://localhost/)
+	router   *mux.Router
+	relative bool
+}
+
+// NewURLBuilder creates a URLBuilder with provided root url object.
+func NewURLBuilder(root *url.URL, relative bool) *URLBuilder {
+	return &URLBuilder{
+		root:     root,
+		router:   Router(),
+		relative: relative,
+	}
+}
+
+// NewURLBuilderFromString workes identically to NewURLBuilder except it takes
+// a string argument for the root, returning an error if it is not a valid
+// url.
+func NewURLBuilderFromString(root string, relative bool) (*URLBuilder, error) {
+	u, err := url.Parse(root)
+	if err != nil {
+		return nil, err
+	}
+
+	return NewURLBuilder(u, relative), nil
+}
+
+// NewURLBuilderFromRequest uses information from an *http.Request to
+// construct the root url.
+func NewURLBuilderFromRequest(r *http.Request, relative bool) *URLBuilder {
+	var (
+		scheme = "http"
+		host   = r.Host
+	)
+
+	if r.TLS != nil {
+		scheme = "https"
+	} else if len(r.URL.Scheme) > 0 {
+		scheme = r.URL.Scheme
+	}
+
+	// Handle fowarded headers
+	// Prefer "Forwarded" header as defined by rfc7239 if given
+	// see https://tools.ietf.org/html/rfc7239
+	if forwarded := r.Header.Get("Forwarded"); len(forwarded) > 0 {
+		forwardedHeader, _, err := parseForwardedHeader(forwarded)
+		if err == nil {
+			if fproto := forwardedHeader["proto"]; len(fproto) > 0 {
+				scheme = fproto
+			}
+			if fhost := forwardedHeader["host"]; len(fhost) > 0 {
+				host = fhost
+			}
+		}
+	} else {
+		if forwardedProto := r.Header.Get("X-Forwarded-Proto"); len(forwardedProto) > 0 {
+			scheme = forwardedProto
+		}
+		if forwardedHost := r.Header.Get("X-Forwarded-Host"); len(forwardedHost) > 0 {
+			// According to the Apache mod_proxy docs, X-Forwarded-Host can be a
+			// comma-separated list of hosts, to which each proxy appends the
+			// requested host. We want to grab the first from this comma-separated
+			// list.
+			hosts := strings.SplitN(forwardedHost, ",", 2)
+			host = strings.TrimSpace(hosts[0])
+		}
+	}
+
+	basePath := routeDescriptorsMap[RouteNameBase].Path
+
+	requestPath := r.URL.Path
+	index := strings.Index(requestPath, basePath)
+
+	u := &url.URL{
+		Scheme: scheme,
+		Host:   host,
+	}
+
+	if index > 0 {
+		// N.B. index+1 is important because we want to include the trailing /
+		u.Path = requestPath[0 : index+1]
+	}
+
+	return NewURLBuilder(u, relative)
+}
+
+// BuildBaseURL constructs a base url for the API, typically just "/v2/".
+func (ub *URLBuilder) BuildBaseURL() (string, error) {
+	route := ub.cloneRoute(RouteNameBase)
+
+	baseURL, err := route.URL()
+	if err != nil {
+		return "", err
+	}
+
+	return baseURL.String(), nil
+}
+
+// BuildCatalogURL constructs a url get a catalog of repositories
+func (ub *URLBuilder) BuildCatalogURL(values ...url.Values) (string, error) {
+	route := ub.cloneRoute(RouteNameCatalog)
+
+	catalogURL, err := route.URL()
+	if err != nil {
+		return "", err
+	}
+
+	return appendValuesURL(catalogURL, values...).String(), nil
+}
+
+// BuildTagsURL constructs a url to list the tags in the named repository.
+func (ub *URLBuilder) BuildTagsURL(name reference.Named) (string, error) {
+	route := ub.cloneRoute(RouteNameTags)
+
+	tagsURL, err := route.URL("name", name.Name())
+	if err != nil {
+		return "", err
+	}
+
+	return tagsURL.String(), nil
+}
+
+// BuildManifestURL constructs a url for the manifest identified by name and
+// reference. The argument reference may be either a tag or digest.
+func (ub *URLBuilder) BuildManifestURL(ref reference.Named) (string, error) {
+	route := ub.cloneRoute(RouteNameManifest)
+
+	tagOrDigest := ""
+	switch v := ref.(type) {
+	case reference.Tagged:
+		tagOrDigest = v.Tag()
+	case reference.Digested:
+		tagOrDigest = v.Digest().String()
+	default:
+		return "", fmt.Errorf("reference must have a tag or digest")
+	}
+
+	manifestURL, err := route.URL("name", ref.Name(), "reference", tagOrDigest)
+	if err != nil {
+		return "", err
+	}
+
+	return manifestURL.String(), nil
+}
+
+// BuildBlobURL constructs the url for the blob identified by name and dgst.
+func (ub *URLBuilder) BuildBlobURL(ref reference.Canonical) (string, error) {
+	route := ub.cloneRoute(RouteNameBlob)
+
+	layerURL, err := route.URL("name", ref.Name(), "digest", ref.Digest().String())
+	if err != nil {
+		return "", err
+	}
+
+	return layerURL.String(), nil
+}
+
+// BuildBlobUploadURL constructs a url to begin a blob upload in the
+// repository identified by name.
+func (ub *URLBuilder) BuildBlobUploadURL(name reference.Named, values ...url.Values) (string, error) {
+	route := ub.cloneRoute(RouteNameBlobUpload)
+
+	uploadURL, err := route.URL("name", name.Name())
+	if err != nil {
+		return "", err
+	}
+
+	return appendValuesURL(uploadURL, values...).String(), nil
+}
+
+// BuildBlobUploadChunkURL constructs a url for the upload identified by uuid,
+// including any url values. This should generally not be used by clients, as
+// this url is provided by server implementations during the blob upload
+// process.
+func (ub *URLBuilder) BuildBlobUploadChunkURL(name reference.Named, uuid string, values ...url.Values) (string, error) {
+	route := ub.cloneRoute(RouteNameBlobUploadChunk)
+
+	uploadURL, err := route.URL("name", name.Name(), "uuid", uuid)
+	if err != nil {
+		return "", err
+	}
+
+	return appendValuesURL(uploadURL, values...).String(), nil
+}
+
+// clondedRoute returns a clone of the named route from the router. Routes
+// must be cloned to avoid modifying them during url generation.
+func (ub *URLBuilder) cloneRoute(name string) clonedRoute {
+	route := new(mux.Route)
+	root := new(url.URL)
+
+	*route = *ub.router.GetRoute(name) // clone the route
+	*root = *ub.root
+
+	return clonedRoute{Route: route, root: root, relative: ub.relative}
+}
+
+type clonedRoute struct {
+	*mux.Route
+	root     *url.URL
+	relative bool
+}
+
+func (cr clonedRoute) URL(pairs ...string) (*url.URL, error) {
+	routeURL, err := cr.Route.URL(pairs...)
+	if err != nil {
+		return nil, err
+	}
+
+	if cr.relative {
+		return routeURL, nil
+	}
+
+	if routeURL.Scheme == "" && routeURL.User == nil && routeURL.Host == "" {
+		routeURL.Path = routeURL.Path[1:]
+	}
+
+	url := cr.root.ResolveReference(routeURL)
+	url.Scheme = cr.root.Scheme
+	return url, nil
+}
+
+// appendValuesURL appends the parameters to the url.
+func appendValuesURL(u *url.URL, values ...url.Values) *url.URL {
+	merged := u.Query()
+
+	for _, v := range values {
+		for k, vv := range v {
+			merged[k] = append(merged[k], vv...)
+		}
+	}
+
+	u.RawQuery = merged.Encode()
+	return u
+}
+
+// appendValues appends the parameters to the url. Panics if the string is not
+// a url.
+func appendValues(u string, values ...url.Values) string {
+	up, err := url.Parse(u)
+
+	if err != nil {
+		panic(err) // should never happen
+	}
+
+	return appendValuesURL(up, values...).String()
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/auth/challenge/addr.go b/vendor/github.com/docker/distribution/registry/client/auth/challenge/addr.go
new file mode 100644
index 000000000..2c3ebe165
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/auth/challenge/addr.go
@@ -0,0 +1,27 @@
+package challenge
+
+import (
+	"net/url"
+	"strings"
+)
+
+// FROM: https://golang.org/src/net/http/http.go
+// Given a string of the form "host", "host:port", or "[ipv6::address]:port",
+// return true if the string includes a port.
+func hasPort(s string) bool { return strings.LastIndex(s, ":") > strings.LastIndex(s, "]") }
+
+// FROM: http://golang.org/src/net/http/transport.go
+var portMap = map[string]string{
+	"http":  "80",
+	"https": "443",
+}
+
+// canonicalAddr returns url.Host but always with a ":port" suffix
+// FROM: http://golang.org/src/net/http/transport.go
+func canonicalAddr(url *url.URL) string {
+	addr := url.Host
+	if !hasPort(addr) {
+		return addr + ":" + portMap[url.Scheme]
+	}
+	return addr
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/auth/challenge/authchallenge.go b/vendor/github.com/docker/distribution/registry/client/auth/challenge/authchallenge.go
new file mode 100644
index 000000000..c9bdfc355
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/auth/challenge/authchallenge.go
@@ -0,0 +1,237 @@
+package challenge
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+)
+
+// Challenge carries information from a WWW-Authenticate response header.
+// See RFC 2617.
+type Challenge struct {
+	// Scheme is the auth-scheme according to RFC 2617
+	Scheme string
+
+	// Parameters are the auth-params according to RFC 2617
+	Parameters map[string]string
+}
+
+// Manager manages the challenges for endpoints.
+// The challenges are pulled out of HTTP responses. Only
+// responses which expect challenges should be added to
+// the manager, since a non-unauthorized request will be
+// viewed as not requiring challenges.
+type Manager interface {
+	// GetChallenges returns the challenges for the given
+	// endpoint URL.
+	GetChallenges(endpoint url.URL) ([]Challenge, error)
+
+	// AddResponse adds the response to the challenge
+	// manager. The challenges will be parsed out of
+	// the WWW-Authenicate headers and added to the
+	// URL which was produced the response. If the
+	// response was authorized, any challenges for the
+	// endpoint will be cleared.
+	AddResponse(resp *http.Response) error
+}
+
+// NewSimpleManager returns an instance of
+// Manger which only maps endpoints to challenges
+// based on the responses which have been added the
+// manager. The simple manager will make no attempt to
+// perform requests on the endpoints or cache the responses
+// to a backend.
+func NewSimpleManager() Manager {
+	return &simpleManager{
+		Challanges: make(map[string][]Challenge),
+	}
+}
+
+type simpleManager struct {
+	sync.RWMutex
+	Challanges map[string][]Challenge
+}
+
+func normalizeURL(endpoint *url.URL) {
+	endpoint.Host = strings.ToLower(endpoint.Host)
+	endpoint.Host = canonicalAddr(endpoint)
+}
+
+func (m *simpleManager) GetChallenges(endpoint url.URL) ([]Challenge, error) {
+	normalizeURL(&endpoint)
+
+	m.RLock()
+	defer m.RUnlock()
+	challenges := m.Challanges[endpoint.String()]
+	return challenges, nil
+}
+
+func (m *simpleManager) AddResponse(resp *http.Response) error {
+	challenges := ResponseChallenges(resp)
+	if resp.Request == nil {
+		return fmt.Errorf("missing request reference")
+	}
+	urlCopy := url.URL{
+		Path:   resp.Request.URL.Path,
+		Host:   resp.Request.URL.Host,
+		Scheme: resp.Request.URL.Scheme,
+	}
+	normalizeURL(&urlCopy)
+
+	m.Lock()
+	defer m.Unlock()
+	m.Challanges[urlCopy.String()] = challenges
+	return nil
+}
+
+// Octet types from RFC 2616.
+type octetType byte
+
+var octetTypes [256]octetType
+
+const (
+	isToken octetType = 1 << iota
+	isSpace
+)
+
+func init() {
+	// OCTET      = <any 8-bit sequence of data>
+	// CHAR       = <any US-ASCII character (octets 0 - 127)>
+	// CTL        = <any US-ASCII control character (octets 0 - 31) and DEL (127)>
+	// CR         = <US-ASCII CR, carriage return (13)>
+	// LF         = <US-ASCII LF, linefeed (10)>
+	// SP         = <US-ASCII SP, space (32)>
+	// HT         = <US-ASCII HT, horizontal-tab (9)>
+	// <">        = <US-ASCII double-quote mark (34)>
+	// CRLF       = CR LF
+	// LWS        = [CRLF] 1*( SP | HT )
+	// TEXT       = <any OCTET except CTLs, but including LWS>
+	// separators = "(" | ")" | "<" | ">" | "@" | "," | ";" | ":" | "\" | <">
+	//              | "/" | "[" | "]" | "?" | "=" | "{" | "}" | SP | HT
+	// token      = 1*<any CHAR except CTLs or separators>
+	// qdtext     = <any TEXT except <">>
+
+	for c := 0; c < 256; c++ {
+		var t octetType
+		isCtl := c <= 31 || c == 127
+		isChar := 0 <= c && c <= 127
+		isSeparator := strings.IndexRune(" \t\"(),/:;<=>?@[]\\{}", rune(c)) >= 0
+		if strings.IndexRune(" \t\r\n", rune(c)) >= 0 {
+			t |= isSpace
+		}
+		if isChar && !isCtl && !isSeparator {
+			t |= isToken
+		}
+		octetTypes[c] = t
+	}
+}
+
+// ResponseChallenges returns a list of authorization challenges
+// for the given http Response. Challenges are only checked if
+// the response status code was a 401.
+func ResponseChallenges(resp *http.Response) []Challenge {
+	if resp.StatusCode == http.StatusUnauthorized {
+		// Parse the WWW-Authenticate Header and store the challenges
+		// on this endpoint object.
+		return parseAuthHeader(resp.Header)
+	}
+
+	return nil
+}
+
+func parseAuthHeader(header http.Header) []Challenge {
+	challenges := []Challenge{}
+	for _, h := range header[http.CanonicalHeaderKey("WWW-Authenticate")] {
+		v, p := parseValueAndParams(h)
+		if v != "" {
+			challenges = append(challenges, Challenge{Scheme: v, Parameters: p})
+		}
+	}
+	return challenges
+}
+
+func parseValueAndParams(header string) (value string, params map[string]string) {
+	params = make(map[string]string)
+	value, s := expectToken(header)
+	if value == "" {
+		return
+	}
+	value = strings.ToLower(value)
+	s = "," + skipSpace(s)
+	for strings.HasPrefix(s, ",") {
+		var pkey string
+		pkey, s = expectToken(skipSpace(s[1:]))
+		if pkey == "" {
+			return
+		}
+		if !strings.HasPrefix(s, "=") {
+			return
+		}
+		var pvalue string
+		pvalue, s = expectTokenOrQuoted(s[1:])
+		if pvalue == "" {
+			return
+		}
+		pkey = strings.ToLower(pkey)
+		params[pkey] = pvalue
+		s = skipSpace(s)
+	}
+	return
+}
+
+func skipSpace(s string) (rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if octetTypes[s[i]]&isSpace == 0 {
+			break
+		}
+	}
+	return s[i:]
+}
+
+func expectToken(s string) (token, rest string) {
+	i := 0
+	for ; i < len(s); i++ {
+		if octetTypes[s[i]]&isToken == 0 {
+			break
+		}
+	}
+	return s[:i], s[i:]
+}
+
+func expectTokenOrQuoted(s string) (value string, rest string) {
+	if !strings.HasPrefix(s, "\"") {
+		return expectToken(s)
+	}
+	s = s[1:]
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"':
+			return s[:i], s[i+1:]
+		case '\\':
+			p := make([]byte, len(s)-1)
+			j := copy(p, s[:i])
+			escape := true
+			for i = i + 1; i < len(s); i++ {
+				b := s[i]
+				switch {
+				case escape:
+					escape = false
+					p[j] = b
+					j++
+				case b == '\\':
+					escape = true
+				case b == '"':
+					return string(p[:j]), s[i+1:]
+				default:
+					p[j] = b
+					j++
+				}
+			}
+			return "", ""
+		}
+	}
+	return "", ""
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/blob_writer.go b/vendor/github.com/docker/distribution/registry/client/blob_writer.go
new file mode 100644
index 000000000..e3ffcb00f
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/blob_writer.go
@@ -0,0 +1,162 @@
+package client
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"time"
+
+	"github.com/docker/distribution"
+	"github.com/docker/distribution/context"
+)
+
+type httpBlobUpload struct {
+	statter distribution.BlobStatter
+	client  *http.Client
+
+	uuid      string
+	startedAt time.Time
+
+	location string // always the last value of the location header.
+	offset   int64
+	closed   bool
+}
+
+func (hbu *httpBlobUpload) Reader() (io.ReadCloser, error) {
+	panic("Not implemented")
+}
+
+func (hbu *httpBlobUpload) handleErrorResponse(resp *http.Response) error {
+	if resp.StatusCode == http.StatusNotFound {
+		return distribution.ErrBlobUploadUnknown
+	}
+	return HandleErrorResponse(resp)
+}
+
+func (hbu *httpBlobUpload) ReadFrom(r io.Reader) (n int64, err error) {
+	req, err := http.NewRequest("PATCH", hbu.location, ioutil.NopCloser(r))
+	if err != nil {
+		return 0, err
+	}
+	defer req.Body.Close()
+
+	resp, err := hbu.client.Do(req)
+	if err != nil {
+		return 0, err
+	}
+
+	if !SuccessStatus(resp.StatusCode) {
+		return 0, hbu.handleErrorResponse(resp)
+	}
+
+	hbu.uuid = resp.Header.Get("Docker-Upload-UUID")
+	hbu.location, err = sanitizeLocation(resp.Header.Get("Location"), hbu.location)
+	if err != nil {
+		return 0, err
+	}
+	rng := resp.Header.Get("Range")
+	var start, end int64
+	if n, err := fmt.Sscanf(rng, "%d-%d", &start, &end); err != nil {
+		return 0, err
+	} else if n != 2 || end < start {
+		return 0, fmt.Errorf("bad range format: %s", rng)
+	}
+
+	return (end - start + 1), nil
+
+}
+
+func (hbu *httpBlobUpload) Write(p []byte) (n int, err error) {
+	req, err := http.NewRequest("PATCH", hbu.location, bytes.NewReader(p))
+	if err != nil {
+		return 0, err
+	}
+	req.Header.Set("Content-Range", fmt.Sprintf("%d-%d", hbu.offset, hbu.offset+int64(len(p)-1)))
+	req.Header.Set("Content-Length", fmt.Sprintf("%d", len(p)))
+	req.Header.Set("Content-Type", "application/octet-stream")
+
+	resp, err := hbu.client.Do(req)
+	if err != nil {
+		return 0, err
+	}
+
+	if !SuccessStatus(resp.StatusCode) {
+		return 0, hbu.handleErrorResponse(resp)
+	}
+
+	hbu.uuid = resp.Header.Get("Docker-Upload-UUID")
+	hbu.location, err = sanitizeLocation(resp.Header.Get("Location"), hbu.location)
+	if err != nil {
+		return 0, err
+	}
+	rng := resp.Header.Get("Range")
+	var start, end int
+	if n, err := fmt.Sscanf(rng, "%d-%d", &start, &end); err != nil {
+		return 0, err
+	} else if n != 2 || end < start {
+		return 0, fmt.Errorf("bad range format: %s", rng)
+	}
+
+	return (end - start + 1), nil
+
+}
+
+func (hbu *httpBlobUpload) Size() int64 {
+	return hbu.offset
+}
+
+func (hbu *httpBlobUpload) ID() string {
+	return hbu.uuid
+}
+
+func (hbu *httpBlobUpload) StartedAt() time.Time {
+	return hbu.startedAt
+}
+
+func (hbu *httpBlobUpload) Commit(ctx context.Context, desc distribution.Descriptor) (distribution.Descriptor, error) {
+	// TODO(dmcgowan): Check if already finished, if so just fetch
+	req, err := http.NewRequest("PUT", hbu.location, nil)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+
+	values := req.URL.Query()
+	values.Set("digest", desc.Digest.String())
+	req.URL.RawQuery = values.Encode()
+
+	resp, err := hbu.client.Do(req)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	defer resp.Body.Close()
+
+	if !SuccessStatus(resp.StatusCode) {
+		return distribution.Descriptor{}, hbu.handleErrorResponse(resp)
+	}
+
+	return hbu.statter.Stat(ctx, desc.Digest)
+}
+
+func (hbu *httpBlobUpload) Cancel(ctx context.Context) error {
+	req, err := http.NewRequest("DELETE", hbu.location, nil)
+	if err != nil {
+		return err
+	}
+	resp, err := hbu.client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusNotFound || SuccessStatus(resp.StatusCode) {
+		return nil
+	}
+	return hbu.handleErrorResponse(resp)
+}
+
+func (hbu *httpBlobUpload) Close() error {
+	hbu.closed = true
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/errors.go b/vendor/github.com/docker/distribution/registry/client/errors.go
new file mode 100644
index 000000000..52d49d5d2
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/errors.go
@@ -0,0 +1,139 @@
+package client
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/docker/distribution/registry/api/errcode"
+	"github.com/docker/distribution/registry/client/auth/challenge"
+)
+
+// ErrNoErrorsInBody is returned when an HTTP response body parses to an empty
+// errcode.Errors slice.
+var ErrNoErrorsInBody = errors.New("no error details found in HTTP response body")
+
+// UnexpectedHTTPStatusError is returned when an unexpected HTTP status is
+// returned when making a registry api call.
+type UnexpectedHTTPStatusError struct {
+	Status string
+}
+
+func (e *UnexpectedHTTPStatusError) Error() string {
+	return fmt.Sprintf("received unexpected HTTP status: %s", e.Status)
+}
+
+// UnexpectedHTTPResponseError is returned when an expected HTTP status code
+// is returned, but the content was unexpected and failed to be parsed.
+type UnexpectedHTTPResponseError struct {
+	ParseErr   error
+	StatusCode int
+	Response   []byte
+}
+
+func (e *UnexpectedHTTPResponseError) Error() string {
+	return fmt.Sprintf("error parsing HTTP %d response body: %s: %q", e.StatusCode, e.ParseErr.Error(), string(e.Response))
+}
+
+func parseHTTPErrorResponse(statusCode int, r io.Reader) error {
+	var errors errcode.Errors
+	body, err := ioutil.ReadAll(r)
+	if err != nil {
+		return err
+	}
+
+	// For backward compatibility, handle irregularly formatted
+	// messages that contain a "details" field.
+	var detailsErr struct {
+		Details string `json:"details"`
+	}
+	err = json.Unmarshal(body, &detailsErr)
+	if err == nil && detailsErr.Details != "" {
+		switch statusCode {
+		case http.StatusUnauthorized:
+			return errcode.ErrorCodeUnauthorized.WithMessage(detailsErr.Details)
+		case http.StatusTooManyRequests:
+			return errcode.ErrorCodeTooManyRequests.WithMessage(detailsErr.Details)
+		default:
+			return errcode.ErrorCodeUnknown.WithMessage(detailsErr.Details)
+		}
+	}
+
+	if err := json.Unmarshal(body, &errors); err != nil {
+		return &UnexpectedHTTPResponseError{
+			ParseErr:   err,
+			StatusCode: statusCode,
+			Response:   body,
+		}
+	}
+
+	if len(errors) == 0 {
+		// If there was no error specified in the body, return
+		// UnexpectedHTTPResponseError.
+		return &UnexpectedHTTPResponseError{
+			ParseErr:   ErrNoErrorsInBody,
+			StatusCode: statusCode,
+			Response:   body,
+		}
+	}
+
+	return errors
+}
+
+func makeErrorList(err error) []error {
+	if errL, ok := err.(errcode.Errors); ok {
+		return []error(errL)
+	}
+	return []error{err}
+}
+
+func mergeErrors(err1, err2 error) error {
+	return errcode.Errors(append(makeErrorList(err1), makeErrorList(err2)...))
+}
+
+// HandleErrorResponse returns error parsed from HTTP response for an
+// unsuccessful HTTP response code (in the range 400 - 499 inclusive). An
+// UnexpectedHTTPStatusError returned for response code outside of expected
+// range.
+func HandleErrorResponse(resp *http.Response) error {
+	if resp.StatusCode >= 400 && resp.StatusCode < 500 {
+		// Check for OAuth errors within the `WWW-Authenticate` header first
+		// See https://tools.ietf.org/html/rfc6750#section-3
+		for _, c := range challenge.ResponseChallenges(resp) {
+			if c.Scheme == "bearer" {
+				var err errcode.Error
+				// codes defined at https://tools.ietf.org/html/rfc6750#section-3.1
+				switch c.Parameters["error"] {
+				case "invalid_token":
+					err.Code = errcode.ErrorCodeUnauthorized
+				case "insufficient_scope":
+					err.Code = errcode.ErrorCodeDenied
+				default:
+					continue
+				}
+				if description := c.Parameters["error_description"]; description != "" {
+					err.Message = description
+				} else {
+					err.Message = err.Code.Message()
+				}
+
+				return mergeErrors(err, parseHTTPErrorResponse(resp.StatusCode, resp.Body))
+			}
+		}
+		err := parseHTTPErrorResponse(resp.StatusCode, resp.Body)
+		if uErr, ok := err.(*UnexpectedHTTPResponseError); ok && resp.StatusCode == 401 {
+			return errcode.ErrorCodeUnauthorized.WithDetail(uErr.Response)
+		}
+		return err
+	}
+	return &UnexpectedHTTPStatusError{Status: resp.Status}
+}
+
+// SuccessStatus returns true if the argument is a successful HTTP response
+// code (in the range 200 - 399 inclusive).
+func SuccessStatus(status int) bool {
+	return status >= 200 && status <= 399
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/repository.go b/vendor/github.com/docker/distribution/registry/client/repository.go
new file mode 100644
index 000000000..b82a968e2
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/repository.go
@@ -0,0 +1,853 @@
+package client
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/docker/distribution"
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/reference"
+	"github.com/docker/distribution/registry/api/v2"
+	"github.com/docker/distribution/registry/client/transport"
+	"github.com/docker/distribution/registry/storage/cache"
+	"github.com/docker/distribution/registry/storage/cache/memory"
+	"github.com/opencontainers/go-digest"
+)
+
+// Registry provides an interface for calling Repositories, which returns a catalog of repositories.
+type Registry interface {
+	Repositories(ctx context.Context, repos []string, last string) (n int, err error)
+}
+
+// checkHTTPRedirect is a callback that can manipulate redirected HTTP
+// requests. It is used to preserve Accept and Range headers.
+func checkHTTPRedirect(req *http.Request, via []*http.Request) error {
+	if len(via) >= 10 {
+		return errors.New("stopped after 10 redirects")
+	}
+
+	if len(via) > 0 {
+		for headerName, headerVals := range via[0].Header {
+			if headerName != "Accept" && headerName != "Range" {
+				continue
+			}
+			for _, val := range headerVals {
+				// Don't add to redirected request if redirected
+				// request already has a header with the same
+				// name and value.
+				hasValue := false
+				for _, existingVal := range req.Header[headerName] {
+					if existingVal == val {
+						hasValue = true
+						break
+					}
+				}
+				if !hasValue {
+					req.Header.Add(headerName, val)
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+// NewRegistry creates a registry namespace which can be used to get a listing of repositories
+func NewRegistry(ctx context.Context, baseURL string, transport http.RoundTripper) (Registry, error) {
+	ub, err := v2.NewURLBuilderFromString(baseURL, false)
+	if err != nil {
+		return nil, err
+	}
+
+	client := &http.Client{
+		Transport:     transport,
+		Timeout:       1 * time.Minute,
+		CheckRedirect: checkHTTPRedirect,
+	}
+
+	return &registry{
+		client:  client,
+		ub:      ub,
+		context: ctx,
+	}, nil
+}
+
+type registry struct {
+	client  *http.Client
+	ub      *v2.URLBuilder
+	context context.Context
+}
+
+// Repositories returns a lexigraphically sorted catalog given a base URL.  The 'entries' slice will be filled up to the size
+// of the slice, starting at the value provided in 'last'.  The number of entries will be returned along with io.EOF if there
+// are no more entries
+func (r *registry) Repositories(ctx context.Context, entries []string, last string) (int, error) {
+	var numFilled int
+	var returnErr error
+
+	values := buildCatalogValues(len(entries), last)
+	u, err := r.ub.BuildCatalogURL(values)
+	if err != nil {
+		return 0, err
+	}
+
+	resp, err := r.client.Get(u)
+	if err != nil {
+		return 0, err
+	}
+	defer resp.Body.Close()
+
+	if SuccessStatus(resp.StatusCode) {
+		var ctlg struct {
+			Repositories []string `json:"repositories"`
+		}
+		decoder := json.NewDecoder(resp.Body)
+
+		if err := decoder.Decode(&ctlg); err != nil {
+			return 0, err
+		}
+
+		for cnt := range ctlg.Repositories {
+			entries[cnt] = ctlg.Repositories[cnt]
+		}
+		numFilled = len(ctlg.Repositories)
+
+		link := resp.Header.Get("Link")
+		if link == "" {
+			returnErr = io.EOF
+		}
+	} else {
+		return 0, HandleErrorResponse(resp)
+	}
+
+	return numFilled, returnErr
+}
+
+// NewRepository creates a new Repository for the given repository name and base URL.
+func NewRepository(ctx context.Context, name reference.Named, baseURL string, transport http.RoundTripper) (distribution.Repository, error) {
+	ub, err := v2.NewURLBuilderFromString(baseURL, false)
+	if err != nil {
+		return nil, err
+	}
+
+	client := &http.Client{
+		Transport:     transport,
+		CheckRedirect: checkHTTPRedirect,
+		// TODO(dmcgowan): create cookie jar
+	}
+
+	return &repository{
+		client:  client,
+		ub:      ub,
+		name:    name,
+		context: ctx,
+	}, nil
+}
+
+type repository struct {
+	client  *http.Client
+	ub      *v2.URLBuilder
+	context context.Context
+	name    reference.Named
+}
+
+func (r *repository) Named() reference.Named {
+	return r.name
+}
+
+func (r *repository) Blobs(ctx context.Context) distribution.BlobStore {
+	statter := &blobStatter{
+		name:   r.name,
+		ub:     r.ub,
+		client: r.client,
+	}
+	return &blobs{
+		name:    r.name,
+		ub:      r.ub,
+		client:  r.client,
+		statter: cache.NewCachedBlobStatter(memory.NewInMemoryBlobDescriptorCacheProvider(), statter),
+	}
+}
+
+func (r *repository) Manifests(ctx context.Context, options ...distribution.ManifestServiceOption) (distribution.ManifestService, error) {
+	// todo(richardscothern): options should be sent over the wire
+	return &manifests{
+		name:   r.name,
+		ub:     r.ub,
+		client: r.client,
+		etags:  make(map[string]string),
+	}, nil
+}
+
+func (r *repository) Tags(ctx context.Context) distribution.TagService {
+	return &tags{
+		client:  r.client,
+		ub:      r.ub,
+		context: r.context,
+		name:    r.Named(),
+	}
+}
+
+// tags implements remote tagging operations.
+type tags struct {
+	client  *http.Client
+	ub      *v2.URLBuilder
+	context context.Context
+	name    reference.Named
+}
+
+// All returns all tags
+func (t *tags) All(ctx context.Context) ([]string, error) {
+	var tags []string
+
+	u, err := t.ub.BuildTagsURL(t.name)
+	if err != nil {
+		return tags, err
+	}
+
+	for {
+		resp, err := t.client.Get(u)
+		if err != nil {
+			return tags, err
+		}
+		defer resp.Body.Close()
+
+		if SuccessStatus(resp.StatusCode) {
+			b, err := ioutil.ReadAll(resp.Body)
+			if err != nil {
+				return tags, err
+			}
+
+			tagsResponse := struct {
+				Tags []string `json:"tags"`
+			}{}
+			if err := json.Unmarshal(b, &tagsResponse); err != nil {
+				return tags, err
+			}
+			tags = append(tags, tagsResponse.Tags...)
+			if link := resp.Header.Get("Link"); link != "" {
+				u = strings.Trim(strings.Split(link, ";")[0], "<>")
+			} else {
+				return tags, nil
+			}
+		} else {
+			return tags, HandleErrorResponse(resp)
+		}
+	}
+}
+
+func descriptorFromResponse(response *http.Response) (distribution.Descriptor, error) {
+	desc := distribution.Descriptor{}
+	headers := response.Header
+
+	ctHeader := headers.Get("Content-Type")
+	if ctHeader == "" {
+		return distribution.Descriptor{}, errors.New("missing or empty Content-Type header")
+	}
+	desc.MediaType = ctHeader
+
+	digestHeader := headers.Get("Docker-Content-Digest")
+	if digestHeader == "" {
+		bytes, err := ioutil.ReadAll(response.Body)
+		if err != nil {
+			return distribution.Descriptor{}, err
+		}
+		_, desc, err := distribution.UnmarshalManifest(ctHeader, bytes)
+		if err != nil {
+			return distribution.Descriptor{}, err
+		}
+		return desc, nil
+	}
+
+	dgst, err := digest.Parse(digestHeader)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	desc.Digest = dgst
+
+	lengthHeader := headers.Get("Content-Length")
+	if lengthHeader == "" {
+		return distribution.Descriptor{}, errors.New("missing or empty Content-Length header")
+	}
+	length, err := strconv.ParseInt(lengthHeader, 10, 64)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	desc.Size = length
+
+	return desc, nil
+
+}
+
+// Get issues a HEAD request for a Manifest against its named endpoint in order
+// to construct a descriptor for the tag.  If the registry doesn't support HEADing
+// a manifest, fallback to GET.
+func (t *tags) Get(ctx context.Context, tag string) (distribution.Descriptor, error) {
+	ref, err := reference.WithTag(t.name, tag)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	u, err := t.ub.BuildManifestURL(ref)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+
+	newRequest := func(method string) (*http.Response, error) {
+		req, err := http.NewRequest(method, u, nil)
+		if err != nil {
+			return nil, err
+		}
+
+		for _, t := range distribution.ManifestMediaTypes() {
+			req.Header.Add("Accept", t)
+		}
+		resp, err := t.client.Do(req)
+		return resp, err
+	}
+
+	resp, err := newRequest("HEAD")
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	defer resp.Body.Close()
+
+	switch {
+	case resp.StatusCode >= 200 && resp.StatusCode < 400:
+		return descriptorFromResponse(resp)
+	default:
+		// if the response is an error - there will be no body to decode.
+		// Issue a GET request:
+		//   - for data from a server that does not handle HEAD
+		//   - to get error details in case of a failure
+		resp, err = newRequest("GET")
+		if err != nil {
+			return distribution.Descriptor{}, err
+		}
+		defer resp.Body.Close()
+
+		if resp.StatusCode >= 200 && resp.StatusCode < 400 {
+			return descriptorFromResponse(resp)
+		}
+		return distribution.Descriptor{}, HandleErrorResponse(resp)
+	}
+}
+
+func (t *tags) Lookup(ctx context.Context, digest distribution.Descriptor) ([]string, error) {
+	panic("not implemented")
+}
+
+func (t *tags) Tag(ctx context.Context, tag string, desc distribution.Descriptor) error {
+	panic("not implemented")
+}
+
+func (t *tags) Untag(ctx context.Context, tag string) error {
+	panic("not implemented")
+}
+
+type manifests struct {
+	name   reference.Named
+	ub     *v2.URLBuilder
+	client *http.Client
+	etags  map[string]string
+}
+
+func (ms *manifests) Exists(ctx context.Context, dgst digest.Digest) (bool, error) {
+	ref, err := reference.WithDigest(ms.name, dgst)
+	if err != nil {
+		return false, err
+	}
+	u, err := ms.ub.BuildManifestURL(ref)
+	if err != nil {
+		return false, err
+	}
+
+	resp, err := ms.client.Head(u)
+	if err != nil {
+		return false, err
+	}
+
+	if SuccessStatus(resp.StatusCode) {
+		return true, nil
+	} else if resp.StatusCode == http.StatusNotFound {
+		return false, nil
+	}
+	return false, HandleErrorResponse(resp)
+}
+
+// AddEtagToTag allows a client to supply an eTag to Get which will be
+// used for a conditional HTTP request.  If the eTag matches, a nil manifest
+// and ErrManifestNotModified error will be returned. etag is automatically
+// quoted when added to this map.
+func AddEtagToTag(tag, etag string) distribution.ManifestServiceOption {
+	return etagOption{tag, etag}
+}
+
+type etagOption struct{ tag, etag string }
+
+func (o etagOption) Apply(ms distribution.ManifestService) error {
+	if ms, ok := ms.(*manifests); ok {
+		ms.etags[o.tag] = fmt.Sprintf(`"%s"`, o.etag)
+		return nil
+	}
+	return fmt.Errorf("etag options is a client-only option")
+}
+
+// ReturnContentDigest allows a client to set a the content digest on
+// a successful request from the 'Docker-Content-Digest' header. This
+// returned digest is represents the digest which the registry uses
+// to refer to the content and can be used to delete the content.
+func ReturnContentDigest(dgst *digest.Digest) distribution.ManifestServiceOption {
+	return contentDigestOption{dgst}
+}
+
+type contentDigestOption struct{ digest *digest.Digest }
+
+func (o contentDigestOption) Apply(ms distribution.ManifestService) error {
+	return nil
+}
+
+func (ms *manifests) Get(ctx context.Context, dgst digest.Digest, options ...distribution.ManifestServiceOption) (distribution.Manifest, error) {
+	var (
+		digestOrTag string
+		ref         reference.Named
+		err         error
+		contentDgst *digest.Digest
+	)
+
+	for _, option := range options {
+		if opt, ok := option.(distribution.WithTagOption); ok {
+			digestOrTag = opt.Tag
+			ref, err = reference.WithTag(ms.name, opt.Tag)
+			if err != nil {
+				return nil, err
+			}
+		} else if opt, ok := option.(contentDigestOption); ok {
+			contentDgst = opt.digest
+		} else {
+			err := option.Apply(ms)
+			if err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	if digestOrTag == "" {
+		digestOrTag = dgst.String()
+		ref, err = reference.WithDigest(ms.name, dgst)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	u, err := ms.ub.BuildManifestURL(ref)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, t := range distribution.ManifestMediaTypes() {
+		req.Header.Add("Accept", t)
+	}
+
+	if _, ok := ms.etags[digestOrTag]; ok {
+		req.Header.Set("If-None-Match", ms.etags[digestOrTag])
+	}
+
+	resp, err := ms.client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode == http.StatusNotModified {
+		return nil, distribution.ErrManifestNotModified
+	} else if SuccessStatus(resp.StatusCode) {
+		if contentDgst != nil {
+			dgst, err := digest.Parse(resp.Header.Get("Docker-Content-Digest"))
+			if err == nil {
+				*contentDgst = dgst
+			}
+		}
+		mt := resp.Header.Get("Content-Type")
+		body, err := ioutil.ReadAll(resp.Body)
+
+		if err != nil {
+			return nil, err
+		}
+		m, _, err := distribution.UnmarshalManifest(mt, body)
+		if err != nil {
+			return nil, err
+		}
+		return m, nil
+	}
+	return nil, HandleErrorResponse(resp)
+}
+
+// Put puts a manifest.  A tag can be specified using an options parameter which uses some shared state to hold the
+// tag name in order to build the correct upload URL.
+func (ms *manifests) Put(ctx context.Context, m distribution.Manifest, options ...distribution.ManifestServiceOption) (digest.Digest, error) {
+	ref := ms.name
+	var tagged bool
+
+	for _, option := range options {
+		if opt, ok := option.(distribution.WithTagOption); ok {
+			var err error
+			ref, err = reference.WithTag(ref, opt.Tag)
+			if err != nil {
+				return "", err
+			}
+			tagged = true
+		} else {
+			err := option.Apply(ms)
+			if err != nil {
+				return "", err
+			}
+		}
+	}
+	mediaType, p, err := m.Payload()
+	if err != nil {
+		return "", err
+	}
+
+	if !tagged {
+		// generate a canonical digest and Put by digest
+		_, d, err := distribution.UnmarshalManifest(mediaType, p)
+		if err != nil {
+			return "", err
+		}
+		ref, err = reference.WithDigest(ref, d.Digest)
+		if err != nil {
+			return "", err
+		}
+	}
+
+	manifestURL, err := ms.ub.BuildManifestURL(ref)
+	if err != nil {
+		return "", err
+	}
+
+	putRequest, err := http.NewRequest("PUT", manifestURL, bytes.NewReader(p))
+	if err != nil {
+		return "", err
+	}
+
+	putRequest.Header.Set("Content-Type", mediaType)
+
+	resp, err := ms.client.Do(putRequest)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+
+	if SuccessStatus(resp.StatusCode) {
+		dgstHeader := resp.Header.Get("Docker-Content-Digest")
+		dgst, err := digest.Parse(dgstHeader)
+		if err != nil {
+			return "", err
+		}
+
+		return dgst, nil
+	}
+
+	return "", HandleErrorResponse(resp)
+}
+
+func (ms *manifests) Delete(ctx context.Context, dgst digest.Digest) error {
+	ref, err := reference.WithDigest(ms.name, dgst)
+	if err != nil {
+		return err
+	}
+	u, err := ms.ub.BuildManifestURL(ref)
+	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)
+}
+
+// todo(richardscothern): Restore interface and implementation with merge of #1050
+/*func (ms *manifests) Enumerate(ctx context.Context, manifests []distribution.Manifest, last distribution.Manifest) (n int, err error) {
+	panic("not supported")
+}*/
+
+type blobs struct {
+	name   reference.Named
+	ub     *v2.URLBuilder
+	client *http.Client
+
+	statter distribution.BlobDescriptorService
+	distribution.BlobDeleter
+}
+
+func sanitizeLocation(location, base string) (string, error) {
+	baseURL, err := url.Parse(base)
+	if err != nil {
+		return "", err
+	}
+
+	locationURL, err := url.Parse(location)
+	if err != nil {
+		return "", err
+	}
+
+	return baseURL.ResolveReference(locationURL).String(), nil
+}
+
+func (bs *blobs) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	return bs.statter.Stat(ctx, dgst)
+
+}
+
+func (bs *blobs) Get(ctx context.Context, dgst digest.Digest) ([]byte, error) {
+	reader, err := bs.Open(ctx, dgst)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	return ioutil.ReadAll(reader)
+}
+
+func (bs *blobs) Open(ctx context.Context, dgst digest.Digest) (distribution.ReadSeekCloser, error) {
+	ref, err := reference.WithDigest(bs.name, dgst)
+	if err != nil {
+		return nil, err
+	}
+	blobURL, err := bs.ub.BuildBlobURL(ref)
+	if err != nil {
+		return nil, err
+	}
+
+	return transport.NewHTTPReadSeeker(bs.client, blobURL,
+		func(resp *http.Response) error {
+			if resp.StatusCode == http.StatusNotFound {
+				return distribution.ErrBlobUnknown
+			}
+			return HandleErrorResponse(resp)
+		}), nil
+}
+
+func (bs *blobs) ServeBlob(ctx context.Context, w http.ResponseWriter, r *http.Request, dgst digest.Digest) error {
+	panic("not implemented")
+}
+
+func (bs *blobs) Put(ctx context.Context, mediaType string, p []byte) (distribution.Descriptor, error) {
+	writer, err := bs.Create(ctx)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	dgstr := digest.Canonical.Digester()
+	n, err := io.Copy(writer, io.TeeReader(bytes.NewReader(p), dgstr.Hash()))
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	if n < int64(len(p)) {
+		return distribution.Descriptor{}, fmt.Errorf("short copy: wrote %d of %d", n, len(p))
+	}
+
+	desc := distribution.Descriptor{
+		MediaType: mediaType,
+		Size:      int64(len(p)),
+		Digest:    dgstr.Digest(),
+	}
+
+	return writer.Commit(ctx, desc)
+}
+
+type optionFunc func(interface{}) error
+
+func (f optionFunc) Apply(v interface{}) error {
+	return f(v)
+}
+
+// WithMountFrom returns a BlobCreateOption which designates that the blob should be
+// mounted from the given canonical reference.
+func WithMountFrom(ref reference.Canonical) distribution.BlobCreateOption {
+	return optionFunc(func(v interface{}) error {
+		opts, ok := v.(*distribution.CreateOptions)
+		if !ok {
+			return fmt.Errorf("unexpected options type: %T", v)
+		}
+
+		opts.Mount.ShouldMount = true
+		opts.Mount.From = ref
+
+		return nil
+	})
+}
+
+func (bs *blobs) Create(ctx context.Context, options ...distribution.BlobCreateOption) (distribution.BlobWriter, error) {
+	var opts distribution.CreateOptions
+
+	for _, option := range options {
+		err := option.Apply(&opts)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	var values []url.Values
+
+	if opts.Mount.ShouldMount {
+		values = append(values, url.Values{"from": {opts.Mount.From.Name()}, "mount": {opts.Mount.From.Digest().String()}})
+	}
+
+	u, err := bs.ub.BuildBlobUploadURL(bs.name, values...)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := bs.client.Post(u, "", nil)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	switch resp.StatusCode {
+	case http.StatusCreated:
+		desc, err := bs.statter.Stat(ctx, opts.Mount.From.Digest())
+		if err != nil {
+			return nil, err
+		}
+		return nil, distribution.ErrBlobMounted{From: opts.Mount.From, Descriptor: desc}
+	case http.StatusAccepted:
+		// TODO(dmcgowan): Check for invalid UUID
+		uuid := resp.Header.Get("Docker-Upload-UUID")
+		location, err := sanitizeLocation(resp.Header.Get("Location"), u)
+		if err != nil {
+			return nil, err
+		}
+
+		return &httpBlobUpload{
+			statter:   bs.statter,
+			client:    bs.client,
+			uuid:      uuid,
+			startedAt: time.Now(),
+			location:  location,
+		}, nil
+	default:
+		return nil, HandleErrorResponse(resp)
+	}
+}
+
+func (bs *blobs) Resume(ctx context.Context, id string) (distribution.BlobWriter, error) {
+	panic("not implemented")
+}
+
+func (bs *blobs) Delete(ctx context.Context, dgst digest.Digest) error {
+	return bs.statter.Clear(ctx, dgst)
+}
+
+type blobStatter struct {
+	name   reference.Named
+	ub     *v2.URLBuilder
+	client *http.Client
+}
+
+func (bs *blobStatter) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	ref, err := reference.WithDigest(bs.name, dgst)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	u, err := bs.ub.BuildBlobURL(ref)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+
+	resp, err := bs.client.Head(u)
+	if err != nil {
+		return distribution.Descriptor{}, err
+	}
+	defer resp.Body.Close()
+
+	if SuccessStatus(resp.StatusCode) {
+		lengthHeader := resp.Header.Get("Content-Length")
+		if lengthHeader == "" {
+			return distribution.Descriptor{}, fmt.Errorf("missing content-length header for request: %s", u)
+		}
+
+		length, err := strconv.ParseInt(lengthHeader, 10, 64)
+		if err != nil {
+			return distribution.Descriptor{}, fmt.Errorf("error parsing content-length: %v", err)
+		}
+
+		return distribution.Descriptor{
+			MediaType: resp.Header.Get("Content-Type"),
+			Size:      length,
+			Digest:    dgst,
+		}, nil
+	} else if resp.StatusCode == http.StatusNotFound {
+		return distribution.Descriptor{}, distribution.ErrBlobUnknown
+	}
+	return distribution.Descriptor{}, HandleErrorResponse(resp)
+}
+
+func buildCatalogValues(maxEntries int, last string) url.Values {
+	values := url.Values{}
+
+	if maxEntries > 0 {
+		values.Add("n", strconv.Itoa(maxEntries))
+	}
+
+	if last != "" {
+		values.Add("last", last)
+	}
+
+	return values
+}
+
+func (bs *blobStatter) Clear(ctx context.Context, dgst digest.Digest) error {
+	ref, err := reference.WithDigest(bs.name, dgst)
+	if err != nil {
+		return err
+	}
+	blobURL, err := bs.ub.BuildBlobURL(ref)
+	if err != nil {
+		return err
+	}
+
+	req, err := http.NewRequest("DELETE", blobURL, nil)
+	if err != nil {
+		return err
+	}
+
+	resp, err := bs.client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+
+	if SuccessStatus(resp.StatusCode) {
+		return nil
+	}
+	return HandleErrorResponse(resp)
+}
+
+func (bs *blobStatter) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/transport/http_reader.go b/vendor/github.com/docker/distribution/registry/client/transport/http_reader.go
new file mode 100644
index 000000000..e5ff09d75
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/transport/http_reader.go
@@ -0,0 +1,251 @@
+package transport
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"regexp"
+	"strconv"
+)
+
+var (
+	contentRangeRegexp = regexp.MustCompile(`bytes ([0-9]+)-([0-9]+)/([0-9]+|\\*)`)
+
+	// ErrWrongCodeForByteRange is returned if the client sends a request
+	// with a Range header but the server returns a 2xx or 3xx code other
+	// than 206 Partial Content.
+	ErrWrongCodeForByteRange = errors.New("expected HTTP 206 from byte range request")
+)
+
+// ReadSeekCloser combines io.ReadSeeker with io.Closer.
+type ReadSeekCloser interface {
+	io.ReadSeeker
+	io.Closer
+}
+
+// NewHTTPReadSeeker handles reading from an HTTP endpoint using a GET
+// request. When seeking and starting a read from a non-zero offset
+// the a "Range" header will be added which sets the offset.
+// TODO(dmcgowan): Move this into a separate utility package
+func NewHTTPReadSeeker(client *http.Client, url string, errorHandler func(*http.Response) error) ReadSeekCloser {
+	return &httpReadSeeker{
+		client:       client,
+		url:          url,
+		errorHandler: errorHandler,
+	}
+}
+
+type httpReadSeeker struct {
+	client *http.Client
+	url    string
+
+	// errorHandler creates an error from an unsuccessful HTTP response.
+	// This allows the error to be created with the HTTP response body
+	// without leaking the body through a returned error.
+	errorHandler func(*http.Response) error
+
+	size int64
+
+	// rc is the remote read closer.
+	rc io.ReadCloser
+	// readerOffset tracks the offset as of the last read.
+	readerOffset int64
+	// seekOffset allows Seek to override the offset. Seek changes
+	// seekOffset instead of changing readOffset directly so that
+	// connection resets can be delayed and possibly avoided if the
+	// seek is undone (i.e. seeking to the end and then back to the
+	// beginning).
+	seekOffset int64
+	err        error
+}
+
+func (hrs *httpReadSeeker) Read(p []byte) (n int, err error) {
+	if hrs.err != nil {
+		return 0, hrs.err
+	}
+
+	// If we sought to a different position, we need to reset the
+	// connection. This logic is here instead of Seek so that if
+	// a seek is undone before the next read, the connection doesn't
+	// need to be closed and reopened. A common example of this is
+	// seeking to the end to determine the length, and then seeking
+	// back to the original position.
+	if hrs.readerOffset != hrs.seekOffset {
+		hrs.reset()
+	}
+
+	hrs.readerOffset = hrs.seekOffset
+
+	rd, err := hrs.reader()
+	if err != nil {
+		return 0, err
+	}
+
+	n, err = rd.Read(p)
+	hrs.seekOffset += int64(n)
+	hrs.readerOffset += int64(n)
+
+	return n, err
+}
+
+func (hrs *httpReadSeeker) Seek(offset int64, whence int) (int64, error) {
+	if hrs.err != nil {
+		return 0, hrs.err
+	}
+
+	lastReaderOffset := hrs.readerOffset
+
+	if whence == os.SEEK_SET && hrs.rc == nil {
+		// If no request has been made yet, and we are seeking to an
+		// absolute position, set the read offset as well to avoid an
+		// unnecessary request.
+		hrs.readerOffset = offset
+	}
+
+	_, err := hrs.reader()
+	if err != nil {
+		hrs.readerOffset = lastReaderOffset
+		return 0, err
+	}
+
+	newOffset := hrs.seekOffset
+
+	switch whence {
+	case os.SEEK_CUR:
+		newOffset += offset
+	case os.SEEK_END:
+		if hrs.size < 0 {
+			return 0, errors.New("content length not known")
+		}
+		newOffset = hrs.size + offset
+	case os.SEEK_SET:
+		newOffset = offset
+	}
+
+	if newOffset < 0 {
+		err = errors.New("cannot seek to negative position")
+	} else {
+		hrs.seekOffset = newOffset
+	}
+
+	return hrs.seekOffset, err
+}
+
+func (hrs *httpReadSeeker) Close() error {
+	if hrs.err != nil {
+		return hrs.err
+	}
+
+	// close and release reader chain
+	if hrs.rc != nil {
+		hrs.rc.Close()
+	}
+
+	hrs.rc = nil
+
+	hrs.err = errors.New("httpLayer: closed")
+
+	return nil
+}
+
+func (hrs *httpReadSeeker) reset() {
+	if hrs.err != nil {
+		return
+	}
+	if hrs.rc != nil {
+		hrs.rc.Close()
+		hrs.rc = nil
+	}
+}
+
+func (hrs *httpReadSeeker) reader() (io.Reader, error) {
+	if hrs.err != nil {
+		return nil, hrs.err
+	}
+
+	if hrs.rc != nil {
+		return hrs.rc, nil
+	}
+
+	req, err := http.NewRequest("GET", hrs.url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	if hrs.readerOffset > 0 {
+		// If we are at different offset, issue a range request from there.
+		req.Header.Add("Range", fmt.Sprintf("bytes=%d-", hrs.readerOffset))
+		// TODO: get context in here
+		// context.GetLogger(hrs.context).Infof("Range: %s", req.Header.Get("Range"))
+	}
+
+	req.Header.Add("Accept-Encoding", "identity")
+	resp, err := hrs.client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	// Normally would use client.SuccessStatus, but that would be a cyclic
+	// import
+	if resp.StatusCode >= 200 && resp.StatusCode <= 399 {
+		if hrs.readerOffset > 0 {
+			if resp.StatusCode != http.StatusPartialContent {
+				return nil, ErrWrongCodeForByteRange
+			}
+
+			contentRange := resp.Header.Get("Content-Range")
+			if contentRange == "" {
+				return nil, errors.New("no Content-Range header found in HTTP 206 response")
+			}
+
+			submatches := contentRangeRegexp.FindStringSubmatch(contentRange)
+			if len(submatches) < 4 {
+				return nil, fmt.Errorf("could not parse Content-Range header: %s", contentRange)
+			}
+
+			startByte, err := strconv.ParseUint(submatches[1], 10, 64)
+			if err != nil {
+				return nil, fmt.Errorf("could not parse start of range in Content-Range header: %s", contentRange)
+			}
+
+			if startByte != uint64(hrs.readerOffset) {
+				return nil, fmt.Errorf("received Content-Range starting at offset %d instead of requested %d", startByte, hrs.readerOffset)
+			}
+
+			endByte, err := strconv.ParseUint(submatches[2], 10, 64)
+			if err != nil {
+				return nil, fmt.Errorf("could not parse end of range in Content-Range header: %s", contentRange)
+			}
+
+			if submatches[3] == "*" {
+				hrs.size = -1
+			} else {
+				size, err := strconv.ParseUint(submatches[3], 10, 64)
+				if err != nil {
+					return nil, fmt.Errorf("could not parse total size in Content-Range header: %s", contentRange)
+				}
+
+				if endByte+1 != size {
+					return nil, fmt.Errorf("range in Content-Range stops before the end of the content: %s", contentRange)
+				}
+
+				hrs.size = int64(size)
+			}
+		} else if resp.StatusCode == http.StatusOK {
+			hrs.size = resp.ContentLength
+		} else {
+			hrs.size = -1
+		}
+		hrs.rc = resp.Body
+	} else {
+		defer resp.Body.Close()
+		if hrs.errorHandler != nil {
+			return nil, hrs.errorHandler(resp)
+		}
+		return nil, fmt.Errorf("unexpected status resolving reader: %v", resp.Status)
+	}
+
+	return hrs.rc, nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/client/transport/transport.go b/vendor/github.com/docker/distribution/registry/client/transport/transport.go
new file mode 100644
index 000000000..30e45fab0
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/client/transport/transport.go
@@ -0,0 +1,147 @@
+package transport
+
+import (
+	"io"
+	"net/http"
+	"sync"
+)
+
+// RequestModifier represents an object which will do an inplace
+// modification of an HTTP request.
+type RequestModifier interface {
+	ModifyRequest(*http.Request) error
+}
+
+type headerModifier http.Header
+
+// NewHeaderRequestModifier returns a new RequestModifier which will
+// add the given headers to a request.
+func NewHeaderRequestModifier(header http.Header) RequestModifier {
+	return headerModifier(header)
+}
+
+func (h headerModifier) ModifyRequest(req *http.Request) error {
+	for k, s := range http.Header(h) {
+		req.Header[k] = append(req.Header[k], s...)
+	}
+
+	return nil
+}
+
+// NewTransport creates a new transport which will apply modifiers to
+// the request on a RoundTrip call.
+func NewTransport(base http.RoundTripper, modifiers ...RequestModifier) http.RoundTripper {
+	return &transport{
+		Modifiers: modifiers,
+		Base:      base,
+	}
+}
+
+// transport is an http.RoundTripper that makes HTTP requests after
+// copying and modifying the request
+type transport struct {
+	Modifiers []RequestModifier
+	Base      http.RoundTripper
+
+	mu     sync.Mutex                      // guards modReq
+	modReq map[*http.Request]*http.Request // original -> modified
+}
+
+// RoundTrip authorizes and authenticates the request with an
+// access token. If no token exists or token is expired,
+// tries to refresh/fetch a new token.
+func (t *transport) RoundTrip(req *http.Request) (*http.Response, error) {
+	req2 := cloneRequest(req)
+	for _, modifier := range t.Modifiers {
+		if err := modifier.ModifyRequest(req2); err != nil {
+			return nil, err
+		}
+	}
+
+	t.setModReq(req, req2)
+	res, err := t.base().RoundTrip(req2)
+	if err != nil {
+		t.setModReq(req, nil)
+		return nil, err
+	}
+	res.Body = &onEOFReader{
+		rc: res.Body,
+		fn: func() { t.setModReq(req, nil) },
+	}
+	return res, nil
+}
+
+// CancelRequest cancels an in-flight request by closing its connection.
+func (t *transport) CancelRequest(req *http.Request) {
+	type canceler interface {
+		CancelRequest(*http.Request)
+	}
+	if cr, ok := t.base().(canceler); ok {
+		t.mu.Lock()
+		modReq := t.modReq[req]
+		delete(t.modReq, req)
+		t.mu.Unlock()
+		cr.CancelRequest(modReq)
+	}
+}
+
+func (t *transport) base() http.RoundTripper {
+	if t.Base != nil {
+		return t.Base
+	}
+	return http.DefaultTransport
+}
+
+func (t *transport) setModReq(orig, mod *http.Request) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.modReq == nil {
+		t.modReq = make(map[*http.Request]*http.Request)
+	}
+	if mod == nil {
+		delete(t.modReq, orig)
+	} else {
+		t.modReq[orig] = mod
+	}
+}
+
+// cloneRequest returns a clone of the provided *http.Request.
+// The clone is a shallow copy of the struct and its Header map.
+func cloneRequest(r *http.Request) *http.Request {
+	// shallow copy of the struct
+	r2 := new(http.Request)
+	*r2 = *r
+	// deep copy of the Header
+	r2.Header = make(http.Header, len(r.Header))
+	for k, s := range r.Header {
+		r2.Header[k] = append([]string(nil), s...)
+	}
+
+	return r2
+}
+
+type onEOFReader struct {
+	rc io.ReadCloser
+	fn func()
+}
+
+func (r *onEOFReader) Read(p []byte) (n int, err error) {
+	n, err = r.rc.Read(p)
+	if err == io.EOF {
+		r.runFunc()
+	}
+	return
+}
+
+func (r *onEOFReader) Close() error {
+	err := r.rc.Close()
+	r.runFunc()
+	return err
+}
+
+func (r *onEOFReader) runFunc() {
+	if fn := r.fn; fn != nil {
+		fn()
+		r.fn = nil
+	}
+}
diff --git a/vendor/github.com/docker/distribution/registry/storage/cache/cache.go b/vendor/github.com/docker/distribution/registry/storage/cache/cache.go
new file mode 100644
index 000000000..10a390919
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/storage/cache/cache.go
@@ -0,0 +1,35 @@
+// Package cache provides facilities to speed up access to the storage
+// backend.
+package cache
+
+import (
+	"fmt"
+
+	"github.com/docker/distribution"
+)
+
+// BlobDescriptorCacheProvider provides repository scoped
+// BlobDescriptorService cache instances and a global descriptor cache.
+type BlobDescriptorCacheProvider interface {
+	distribution.BlobDescriptorService
+
+	RepositoryScoped(repo string) (distribution.BlobDescriptorService, error)
+}
+
+// ValidateDescriptor provides a helper function to ensure that caches have
+// common criteria for admitting descriptors.
+func ValidateDescriptor(desc distribution.Descriptor) error {
+	if err := desc.Digest.Validate(); err != nil {
+		return err
+	}
+
+	if desc.Size < 0 {
+		return fmt.Errorf("cache: invalid length in descriptor: %v < 0", desc.Size)
+	}
+
+	if desc.MediaType == "" {
+		return fmt.Errorf("cache: empty mediatype on descriptor: %v", desc)
+	}
+
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/storage/cache/cachedblobdescriptorstore.go b/vendor/github.com/docker/distribution/registry/storage/cache/cachedblobdescriptorstore.go
new file mode 100644
index 000000000..f647616bc
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/storage/cache/cachedblobdescriptorstore.go
@@ -0,0 +1,101 @@
+package cache
+
+import (
+	"github.com/docker/distribution/context"
+	"github.com/opencontainers/go-digest"
+
+	"github.com/docker/distribution"
+)
+
+// Metrics is used to hold metric counters
+// related to the number of times a cache was
+// hit or missed.
+type Metrics struct {
+	Requests uint64
+	Hits     uint64
+	Misses   uint64
+}
+
+// MetricsTracker represents a metric tracker
+// which simply counts the number of hits and misses.
+type MetricsTracker interface {
+	Hit()
+	Miss()
+	Metrics() Metrics
+}
+
+type cachedBlobStatter struct {
+	cache   distribution.BlobDescriptorService
+	backend distribution.BlobDescriptorService
+	tracker MetricsTracker
+}
+
+// NewCachedBlobStatter creates a new statter which prefers a cache and
+// falls back to a backend.
+func NewCachedBlobStatter(cache distribution.BlobDescriptorService, backend distribution.BlobDescriptorService) distribution.BlobDescriptorService {
+	return &cachedBlobStatter{
+		cache:   cache,
+		backend: backend,
+	}
+}
+
+// NewCachedBlobStatterWithMetrics creates a new statter which prefers a cache and
+// falls back to a backend. Hits and misses will send to the tracker.
+func NewCachedBlobStatterWithMetrics(cache distribution.BlobDescriptorService, backend distribution.BlobDescriptorService, tracker MetricsTracker) distribution.BlobStatter {
+	return &cachedBlobStatter{
+		cache:   cache,
+		backend: backend,
+		tracker: tracker,
+	}
+}
+
+func (cbds *cachedBlobStatter) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	desc, err := cbds.cache.Stat(ctx, dgst)
+	if err != nil {
+		if err != distribution.ErrBlobUnknown {
+			context.GetLogger(ctx).Errorf("error retrieving descriptor from cache: %v", err)
+		}
+
+		goto fallback
+	}
+
+	if cbds.tracker != nil {
+		cbds.tracker.Hit()
+	}
+	return desc, nil
+fallback:
+	if cbds.tracker != nil {
+		cbds.tracker.Miss()
+	}
+	desc, err = cbds.backend.Stat(ctx, dgst)
+	if err != nil {
+		return desc, err
+	}
+
+	if err := cbds.cache.SetDescriptor(ctx, dgst, desc); err != nil {
+		context.GetLogger(ctx).Errorf("error adding descriptor %v to cache: %v", desc.Digest, err)
+	}
+
+	return desc, err
+
+}
+
+func (cbds *cachedBlobStatter) Clear(ctx context.Context, dgst digest.Digest) error {
+	err := cbds.cache.Clear(ctx, dgst)
+	if err != nil {
+		return err
+	}
+
+	err = cbds.backend.Clear(ctx, dgst)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (cbds *cachedBlobStatter) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
+	if err := cbds.cache.SetDescriptor(ctx, dgst, desc); err != nil {
+		context.GetLogger(ctx).Errorf("error adding descriptor %v to cache: %v", desc.Digest, err)
+	}
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/registry/storage/cache/memory/memory.go b/vendor/github.com/docker/distribution/registry/storage/cache/memory/memory.go
new file mode 100644
index 000000000..b2fcaf4e8
--- /dev/null
+++ b/vendor/github.com/docker/distribution/registry/storage/cache/memory/memory.go
@@ -0,0 +1,179 @@
+package memory
+
+import (
+	"sync"
+
+	"github.com/docker/distribution"
+	"github.com/docker/distribution/context"
+	"github.com/docker/distribution/reference"
+	"github.com/docker/distribution/registry/storage/cache"
+	"github.com/opencontainers/go-digest"
+)
+
+type inMemoryBlobDescriptorCacheProvider struct {
+	global       *mapBlobDescriptorCache
+	repositories map[string]*mapBlobDescriptorCache
+	mu           sync.RWMutex
+}
+
+// NewInMemoryBlobDescriptorCacheProvider returns a new mapped-based cache for
+// storing blob descriptor data.
+func NewInMemoryBlobDescriptorCacheProvider() cache.BlobDescriptorCacheProvider {
+	return &inMemoryBlobDescriptorCacheProvider{
+		global:       newMapBlobDescriptorCache(),
+		repositories: make(map[string]*mapBlobDescriptorCache),
+	}
+}
+
+func (imbdcp *inMemoryBlobDescriptorCacheProvider) RepositoryScoped(repo string) (distribution.BlobDescriptorService, error) {
+	if _, err := reference.ParseNormalizedNamed(repo); err != nil {
+		return nil, err
+	}
+
+	imbdcp.mu.RLock()
+	defer imbdcp.mu.RUnlock()
+
+	return &repositoryScopedInMemoryBlobDescriptorCache{
+		repo:       repo,
+		parent:     imbdcp,
+		repository: imbdcp.repositories[repo],
+	}, nil
+}
+
+func (imbdcp *inMemoryBlobDescriptorCacheProvider) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	return imbdcp.global.Stat(ctx, dgst)
+}
+
+func (imbdcp *inMemoryBlobDescriptorCacheProvider) Clear(ctx context.Context, dgst digest.Digest) error {
+	return imbdcp.global.Clear(ctx, dgst)
+}
+
+func (imbdcp *inMemoryBlobDescriptorCacheProvider) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
+	_, err := imbdcp.Stat(ctx, dgst)
+	if err == distribution.ErrBlobUnknown {
+
+		if dgst.Algorithm() != desc.Digest.Algorithm() && dgst != desc.Digest {
+			// if the digests differ, set the other canonical mapping
+			if err := imbdcp.global.SetDescriptor(ctx, desc.Digest, desc); err != nil {
+				return err
+			}
+		}
+
+		// unknown, just set it
+		return imbdcp.global.SetDescriptor(ctx, dgst, desc)
+	}
+
+	// we already know it, do nothing
+	return err
+}
+
+// repositoryScopedInMemoryBlobDescriptorCache provides the request scoped
+// repository cache. Instances are not thread-safe but the delegated
+// operations are.
+type repositoryScopedInMemoryBlobDescriptorCache struct {
+	repo       string
+	parent     *inMemoryBlobDescriptorCacheProvider // allows lazy allocation of repo's map
+	repository *mapBlobDescriptorCache
+}
+
+func (rsimbdcp *repositoryScopedInMemoryBlobDescriptorCache) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	rsimbdcp.parent.mu.Lock()
+	repo := rsimbdcp.repository
+	rsimbdcp.parent.mu.Unlock()
+
+	if repo == nil {
+		return distribution.Descriptor{}, distribution.ErrBlobUnknown
+	}
+
+	return repo.Stat(ctx, dgst)
+}
+
+func (rsimbdcp *repositoryScopedInMemoryBlobDescriptorCache) Clear(ctx context.Context, dgst digest.Digest) error {
+	rsimbdcp.parent.mu.Lock()
+	repo := rsimbdcp.repository
+	rsimbdcp.parent.mu.Unlock()
+
+	if repo == nil {
+		return distribution.ErrBlobUnknown
+	}
+
+	return repo.Clear(ctx, dgst)
+}
+
+func (rsimbdcp *repositoryScopedInMemoryBlobDescriptorCache) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
+	rsimbdcp.parent.mu.Lock()
+	repo := rsimbdcp.repository
+	if repo == nil {
+		// allocate map since we are setting it now.
+		var ok bool
+		// have to read back value since we may have allocated elsewhere.
+		repo, ok = rsimbdcp.parent.repositories[rsimbdcp.repo]
+		if !ok {
+			repo = newMapBlobDescriptorCache()
+			rsimbdcp.parent.repositories[rsimbdcp.repo] = repo
+		}
+		rsimbdcp.repository = repo
+	}
+	rsimbdcp.parent.mu.Unlock()
+
+	if err := repo.SetDescriptor(ctx, dgst, desc); err != nil {
+		return err
+	}
+
+	return rsimbdcp.parent.SetDescriptor(ctx, dgst, desc)
+}
+
+// mapBlobDescriptorCache provides a simple map-based implementation of the
+// descriptor cache.
+type mapBlobDescriptorCache struct {
+	descriptors map[digest.Digest]distribution.Descriptor
+	mu          sync.RWMutex
+}
+
+var _ distribution.BlobDescriptorService = &mapBlobDescriptorCache{}
+
+func newMapBlobDescriptorCache() *mapBlobDescriptorCache {
+	return &mapBlobDescriptorCache{
+		descriptors: make(map[digest.Digest]distribution.Descriptor),
+	}
+}
+
+func (mbdc *mapBlobDescriptorCache) Stat(ctx context.Context, dgst digest.Digest) (distribution.Descriptor, error) {
+	if err := dgst.Validate(); err != nil {
+		return distribution.Descriptor{}, err
+	}
+
+	mbdc.mu.RLock()
+	defer mbdc.mu.RUnlock()
+
+	desc, ok := mbdc.descriptors[dgst]
+	if !ok {
+		return distribution.Descriptor{}, distribution.ErrBlobUnknown
+	}
+
+	return desc, nil
+}
+
+func (mbdc *mapBlobDescriptorCache) Clear(ctx context.Context, dgst digest.Digest) error {
+	mbdc.mu.Lock()
+	defer mbdc.mu.Unlock()
+
+	delete(mbdc.descriptors, dgst)
+	return nil
+}
+
+func (mbdc *mapBlobDescriptorCache) SetDescriptor(ctx context.Context, dgst digest.Digest, desc distribution.Descriptor) error {
+	if err := dgst.Validate(); err != nil {
+		return err
+	}
+
+	if err := cache.ValidateDescriptor(desc); err != nil {
+		return err
+	}
+
+	mbdc.mu.Lock()
+	defer mbdc.mu.Unlock()
+
+	mbdc.descriptors[dgst] = desc
+	return nil
+}
diff --git a/vendor/github.com/docker/distribution/tags.go b/vendor/github.com/docker/distribution/tags.go
new file mode 100644
index 000000000..503056596
--- /dev/null
+++ b/vendor/github.com/docker/distribution/tags.go
@@ -0,0 +1,27 @@
+package distribution
+
+import (
+	"github.com/docker/distribution/context"
+)
+
+// TagService provides access to information about tagged objects.
+type TagService interface {
+	// Get retrieves the descriptor identified by the tag. Some
+	// implementations may differentiate between "trusted" tags and
+	// "untrusted" tags. If a tag is "untrusted", the mapping will be returned
+	// as an ErrTagUntrusted error, with the target descriptor.
+	Get(ctx context.Context, tag string) (Descriptor, error)
+
+	// Tag associates the tag with the provided descriptor, updating the
+	// current association, if needed.
+	Tag(ctx context.Context, tag string, desc Descriptor) error
+
+	// Untag removes the given tag association
+	Untag(ctx context.Context, tag string) error
+
+	// All returns the set of tags managed by this tag service
+	All(ctx context.Context) ([]string, error)
+
+	// Lookup returns the set of tags referencing the given digest.
+	Lookup(ctx context.Context, digest Descriptor) ([]string, error)
+}
diff --git a/vendor/github.com/docker/distribution/uuid/uuid.go b/vendor/github.com/docker/distribution/uuid/uuid.go
new file mode 100644
index 000000000..d433ccaf5
--- /dev/null
+++ b/vendor/github.com/docker/distribution/uuid/uuid.go
@@ -0,0 +1,126 @@
+// Package uuid provides simple UUID generation. Only version 4 style UUIDs
+// can be generated.
+//
+// Please see http://tools.ietf.org/html/rfc4122 for details on UUIDs.
+package uuid
+
+import (
+	"crypto/rand"
+	"fmt"
+	"io"
+	"os"
+	"syscall"
+	"time"
+)
+
+const (
+	// Bits is the number of bits in a UUID
+	Bits = 128
+
+	// Size is the number of bytes in a UUID
+	Size = Bits / 8
+
+	format = "%08x-%04x-%04x-%04x-%012x"
+)
+
+var (
+	// ErrUUIDInvalid indicates a parsed string is not a valid uuid.
+	ErrUUIDInvalid = fmt.Errorf("invalid uuid")
+
+	// Loggerf can be used to override the default logging destination. Such
+	// log messages in this library should be logged at warning or higher.
+	Loggerf = func(format string, args ...interface{}) {}
+)
+
+// UUID represents a UUID value. UUIDs can be compared and set to other values
+// and accessed by byte.
+type UUID [Size]byte
+
+// Generate creates a new, version 4 uuid.
+func Generate() (u UUID) {
+	const (
+		// ensures we backoff for less than 450ms total. Use the following to
+		// select new value, in units of 10ms:
+		// 	n*(n+1)/2 = d -> n^2 + n - 2d -> n = (sqrt(8d + 1) - 1)/2
+		maxretries = 9
+		backoff    = time.Millisecond * 10
+	)
+
+	var (
+		totalBackoff time.Duration
+		count        int
+		retries      int
+	)
+
+	for {
+		// This should never block but the read may fail. Because of this,
+		// we just try to read the random number generator until we get
+		// something. This is a very rare condition but may happen.
+		b := time.Duration(retries) * backoff
+		time.Sleep(b)
+		totalBackoff += b
+
+		n, err := io.ReadFull(rand.Reader, u[count:])
+		if err != nil {
+			if retryOnError(err) && retries < maxretries {
+				count += n
+				retries++
+				Loggerf("error generating version 4 uuid, retrying: %v", err)
+				continue
+			}
+
+			// Any other errors represent a system problem. What did someone
+			// do to /dev/urandom?
+			panic(fmt.Errorf("error reading random number generator, retried for %v: %v", totalBackoff.String(), err))
+		}
+
+		break
+	}
+
+	u[6] = (u[6] & 0x0f) | 0x40 // set version byte
+	u[8] = (u[8] & 0x3f) | 0x80 // set high order byte 0b10{8,9,a,b}
+
+	return u
+}
+
+// Parse attempts to extract a uuid from the string or returns an error.
+func Parse(s string) (u UUID, err error) {
+	if len(s) != 36 {
+		return UUID{}, ErrUUIDInvalid
+	}
+
+	// create stack addresses for each section of the uuid.
+	p := make([][]byte, 5)
+
+	if _, err := fmt.Sscanf(s, format, &p[0], &p[1], &p[2], &p[3], &p[4]); err != nil {
+		return u, err
+	}
+
+	copy(u[0:4], p[0])
+	copy(u[4:6], p[1])
+	copy(u[6:8], p[2])
+	copy(u[8:10], p[3])
+	copy(u[10:16], p[4])
+
+	return
+}
+
+func (u UUID) String() string {
+	return fmt.Sprintf(format, u[:4], u[4:6], u[6:8], u[8:10], u[10:])
+}
+
+// retryOnError tries to detect whether or not retrying would be fruitful.
+func retryOnError(err error) bool {
+	switch err := err.(type) {
+	case *os.PathError:
+		return retryOnError(err.Err) // unpack the target error
+	case syscall.Errno:
+		if err == syscall.EPERM {
+			// EPERM represents an entropy pool exhaustion, a condition under
+			// which we backoff and retry.
+			return true
+		}
+	}
+
+	return false
+}
diff --git a/vendor/github.com/docker/distribution/vendor.conf b/vendor/github.com/docker/distribution/vendor.conf
new file mode 100644
index 000000000..d67edd779
--- /dev/null
+++ b/vendor/github.com/docker/distribution/vendor.conf
@@ -0,0 +1,43 @@
+github.com/Azure/azure-sdk-for-go 088007b3b08cc02b27f2eadfdcd870958460ce7e
+github.com/Azure/go-autorest ec5f4903f77ed9927ac95b19ab8e44ada64c1356
+github.com/sirupsen/logrus 3d4380f53a34dcdc95f0c1db702615992b38d9a4
+github.com/aws/aws-sdk-go c6fc52983ea2375810aa38ddb5370e9cdf611716
+github.com/bshuster-repo/logrus-logstash-hook d2c0ecc1836d91814e15e23bb5dc309c3ef51f4a
+github.com/bugsnag/bugsnag-go b1d153021fcd90ca3f080db36bec96dc690fb274
+github.com/bugsnag/osext 0dd3f918b21bec95ace9dc86c7e70266cfc5c702
+github.com/bugsnag/panicwrap e2c28503fcd0675329da73bf48b33404db873782
+github.com/denverdino/aliyungo afedced274aa9a7fcdd47ac97018f0f8db4e5de2
+github.com/dgrijalva/jwt-go a601269ab70c205d26370c16f7c81e9017c14e04
+github.com/docker/goamz f0a21f5b2e12f83a505ecf79b633bb2035cf6f85
+github.com/docker/libtrust fa567046d9b14f6aa788882a950d69651d230b21
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