Move layer interface definitions to distribution package

After consideration, it has been decided that the interfaces defined in the
storage package provide a good base for interacting with various registry
instances. Whether interacting with a remote API or a local, on-disk registry,
these types have proved flexible. By moving them here, they can become the
central components of interacting with distribution components.

Signed-off-by: Stephen J Day <stephen.day@docker.com>

docs/handlers/app.go

@@ -7,8 +7,10 @@ import (
 	"os"
 
 	"code.google.com/p/go-uuid/uuid"
+	"github.com/docker/distribution"
 	"github.com/docker/distribution/configuration"
 	ctxu "github.com/docker/distribution/context"
+	"github.com/docker/distribution/notifications"
 	"github.com/docker/distribution/registry/api/v2"
 	"github.com/docker/distribution/registry/auth"
 	"github.com/docker/distribution/registry/storage"
@@ -32,7 +34,7 @@ type App struct {
 
 	router           *mux.Router                 // main application router, configured with dispatchers
 	driver           storagedriver.StorageDriver // driver maintains the app global storage driver instance.
-	registry         storage.Registry            // registry is the primary registry backend for the app instance.
+	registry         distribution.Registry       // registry is the primary registry backend for the app instance.
 	accessController auth.AccessController       // main access controller for application
 
 	// events contains notification related configuration.

docs/handlers/context.go

@@ -4,10 +4,10 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/docker/distribution"
 	ctxu "github.com/docker/distribution/context"
 	"github.com/docker/distribution/digest"
 	"github.com/docker/distribution/registry/api/v2"
-	"github.com/docker/distribution/registry/storage"
 	"golang.org/x/net/context"
 )
 
@@ -21,7 +21,7 @@ type Context struct {
 
 	// Repository is the repository for the current request. All requests
 	// should be scoped to a single repository. This field may be nil.
-	Repository storage.Repository
+	Repository distribution.Repository
 
 	// Errors is a collection of errors encountered during the request to be
 	// returned to the client API. If errors are added to the collection, the

docs/handlers/images.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net/http"
 
+	"github.com/docker/distribution"
 	ctxu "github.com/docker/distribution/context"
 	"github.com/docker/distribution/digest"
 	"github.com/docker/distribution/manifest"
@@ -72,7 +73,7 @@ func (imh *imageManifestHandler) PutImageManifest(w http.ResponseWriter, r *http
 		case storage.ErrManifestVerification:
 			for _, verificationError := range err {
 				switch verificationError := verificationError.(type) {
-				case storage.ErrUnknownLayer:
+				case distribution.ErrUnknownLayer:
 					imh.Errors.Push(v2.ErrorCodeBlobUnknown, verificationError.FSLayer)
 				case storage.ErrManifestUnverified:
 					imh.Errors.Push(v2.ErrorCodeManifestUnverified)

docs/handlers/layer.go

@@ -3,10 +3,10 @@ package handlers
 import (
 	"net/http"
 
+	"github.com/docker/distribution"
 	ctxu "github.com/docker/distribution/context"
 	"github.com/docker/distribution/digest"
 	"github.com/docker/distribution/registry/api/v2"
-	"github.com/docker/distribution/registry/storage"
 	"github.com/gorilla/handlers"
 )
 
@@ -54,7 +54,7 @@ func (lh *layerHandler) GetLayer(w http.ResponseWriter, r *http.Request) {
 
 	if err != nil {
 		switch err := err.(type) {
-		case storage.ErrUnknownLayer:
+		case distribution.ErrUnknownLayer:
 			w.WriteHeader(http.StatusNotFound)
 			lh.Errors.Push(v2.ErrorCodeBlobUnknown, err.FSLayer)
 		default:

docs/handlers/layerupload.go

@@ -7,10 +7,10 @@ import (
 	"net/url"
 	"os"
 
+	"github.com/docker/distribution"
 	ctxu "github.com/docker/distribution/context"
 	"github.com/docker/distribution/digest"
 	"github.com/docker/distribution/registry/api/v2"
-	"github.com/docker/distribution/registry/storage"
 	"github.com/gorilla/handlers"
 )
 
@@ -63,7 +63,7 @@ func layerUploadDispatcher(ctx *Context, r *http.Request) http.Handler {
 		upload, err := layers.Resume(luh.UUID)
 		if err != nil {
 			ctxu.GetLogger(ctx).Errorf("error resolving upload: %v", err)
-			if err == storage.ErrLayerUploadUnknown {
+			if err == distribution.ErrLayerUploadUnknown {
 				return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 					w.WriteHeader(http.StatusNotFound)
 					luh.Errors.Push(v2.ErrorCodeBlobUploadUnknown, err)
@@ -114,7 +114,7 @@ type layerUploadHandler struct {
 	// UUID identifies the upload instance for the current request.
 	UUID string
 
-	Upload storage.LayerUpload
+	Upload distribution.LayerUpload
 
 	State layerUploadState
 }
@@ -196,7 +196,7 @@ func (luh *layerUploadHandler) PutLayerUploadComplete(w http.ResponseWriter, r *
 	layer, err := luh.Upload.Finish(dgst)
 	if err != nil {
 		switch err := err.(type) {
-		case storage.ErrLayerInvalidDigest:
+		case distribution.ErrLayerInvalidDigest:
 			w.WriteHeader(http.StatusBadRequest)
 			luh.Errors.Push(v2.ErrorCodeDigestInvalid, err)
 		default: