registry: Remove reference.go

This removes some very old vestigial code that really should have been
removed during the content addressability transition. It implements
something called "reference" but it behaves differently from the actual
reference package. This was only used by client-side content trust code,
and is relatively easy to extricate.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>

cli/command/image/pull.go

@@ -55,16 +55,6 @@ func runPull(dockerCli *command.DockerCli, opts pullOptions) error {
 		fmt.Fprintf(dockerCli.Out(), "Using default tag: %s\n", reference.DefaultTag)
 	}
 
-	var tag string
-	switch x := distributionRef.(type) {
-	case reference.Canonical:
-		tag = x.Digest().String()
-	case reference.NamedTagged:
-		tag = x.Tag()
-	}
-
-	registryRef := registry.ParseReference(tag)
-
 	// Resolve the Repository name from fqn to RepositoryInfo
 	repoInfo, err := registry.ParseRepositoryInfo(distributionRef)
 	if err != nil {
@@ -76,9 +66,10 @@ func runPull(dockerCli *command.DockerCli, opts pullOptions) error {
 	authConfig := command.ResolveAuthConfig(ctx, dockerCli, repoInfo.Index)
 	requestPrivilege := command.RegistryAuthenticationPrivilegedFunc(dockerCli, repoInfo.Index, "pull")
 
-	if command.IsTrusted() && !registryRef.HasDigest() {
-		// Check if tag is digest
-		err = trustedPull(ctx, dockerCli, repoInfo, registryRef, authConfig, requestPrivilege)
+	// Check if reference has a digest
+	_, isCanonical := distributionRef.(reference.Canonical)
+	if command.IsTrusted() && !isCanonical {
+		err = trustedPull(ctx, dockerCli, repoInfo, distributionRef, authConfig, requestPrivilege)
 	} else {
 		err = imagePullPrivileged(ctx, dockerCli, authConfig, distributionRef.String(), requestPrivilege, opts.all)
 	}

cli/command/image/trust.go

@@ -46,9 +46,9 @@ var (
 )
 
 type target struct {
-	reference registry.Reference
-	digest    digest.Digest
-	size      int64
+	name   string
+	digest digest.Digest
+	size   int64
 }
 
 // trustedPush handles content trust pushing of an image
@@ -81,7 +81,7 @@ func trustedPush(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 				target = nil
 				return
 			}
-			target.Name = registry.ParseReference(pushResult.Tag).String()
+			target.Name = pushResult.Tag
 			target.Hashes = data.Hashes{string(pushResult.Digest.Algorithm()): h}
 			target.Length = int64(pushResult.Size)
 		}
@@ -93,11 +93,9 @@ func trustedPush(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 		return errors.New("cannot push a digest reference")
 	case reference.NamedTagged:
 		tag = x.Tag()
-	}
-
-	// We want trust signatures to always take an explicit tag,
-	// otherwise it will act as an untrusted push.
-	if tag == "" {
+	default:
+		// We want trust signatures to always take an explicit tag,
+		// otherwise it will act as an untrusted push.
 		if err = jsonmessage.DisplayJSONMessagesToStream(responseBody, cli.Out(), nil); err != nil {
 			return err
 		}
@@ -234,7 +232,7 @@ func imagePushPrivileged(ctx context.Context, cli *command.DockerCli, authConfig
 }
 
 // trustedPull handles content trust pulling of an image
-func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry.RepositoryInfo, ref registry.Reference, authConfig types.AuthConfig, requestPrivilege types.RequestPrivilegeFunc) error {
+func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry.RepositoryInfo, ref reference.Named, authConfig types.AuthConfig, requestPrivilege types.RequestPrivilegeFunc) error {
 	var refs []target
 
 	notaryRepo, err := GetNotaryRepository(cli, repoInfo, authConfig, "pull")
@@ -243,7 +241,7 @@ func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 		return err
 	}
 
-	if ref.String() == "" {
+	if tagged, isTagged := ref.(reference.NamedTagged); !isTagged {
 		// List all targets
 		targets, err := notaryRepo.ListTargets(releasesRole, data.CanonicalTargetsRole)
 		if err != nil {
@@ -266,14 +264,14 @@ func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 			return notaryError(repoInfo.FullName(), fmt.Errorf("No trusted tags for %s", repoInfo.FullName()))
 		}
 	} else {
-		t, err := notaryRepo.GetTargetByName(ref.String(), releasesRole, data.CanonicalTargetsRole)
+		t, err := notaryRepo.GetTargetByName(tagged.Tag(), releasesRole, data.CanonicalTargetsRole)
 		if err != nil {
 			return notaryError(repoInfo.FullName(), err)
 		}
 		// Only get the tag if it's in the top level targets role or the releases delegation role
 		// ignore it if it's in any other delegation roles
 		if t.Role != releasesRole && t.Role != data.CanonicalTargetsRole {
-			return notaryError(repoInfo.FullName(), fmt.Errorf("No trust data for %s", ref.String()))
+			return notaryError(repoInfo.FullName(), fmt.Errorf("No trust data for %s", tagged.Tag()))
 		}
 
 		logrus.Debugf("retrieving target for %s role\n", t.Role)
@@ -286,7 +284,7 @@ func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 	}
 
 	for i, r := range refs {
-		displayTag := r.reference.String()
+		displayTag := r.name
 		if displayTag != "" {
 			displayTag = ":" + displayTag
 		}
@@ -300,19 +298,16 @@ func trustedPull(ctx context.Context, cli *command.DockerCli, repoInfo *registry
 			return err
 		}
 
-		// If reference is not trusted, tag by trusted reference
-		if !r.reference.HasDigest() {
-			tagged, err := reference.WithTag(repoInfo, r.reference.String())
-			if err != nil {
-				return err
-			}
-			trustedRef, err := reference.WithDigest(reference.TrimNamed(repoInfo), r.digest)
-			if err != nil {
-				return err
-			}
-			if err := TagTrusted(ctx, cli, trustedRef, tagged); err != nil {
-				return err
-			}
+		tagged, err := reference.WithTag(repoInfo, r.name)
+		if err != nil {
+			return err
+		}
+		trustedRef, err := reference.WithDigest(reference.TrimNamed(repoInfo), r.digest)
+		if err != nil {
+			return err
+		}
+		if err := TagTrusted(ctx, cli, trustedRef, tagged); err != nil {
+			return err
 		}
 	}
 	return nil
@@ -533,9 +528,9 @@ func convertTarget(t client.Target) (target, error) {
 		return target{}, errors.New("no valid hash, expecting sha256")
 	}
 	return target{
-		reference: registry.ParseReference(t.Name),
-		digest:    digest.NewDigestFromHex("sha256", hex.EncodeToString(h)),
-		size:      t.Length,
+		name:   t.Name,
+		digest: digest.NewDigestFromHex("sha256", hex.EncodeToString(h)),
+		size:   t.Length,
 	}, nil
 }
 

registry/reference.go

@@ -1,68 +0,0 @@
-package registry
-
-import (
-	"strings"
-
-	"github.com/docker/distribution/digest"
-)
-
-// Reference represents a tag or digest within a repository
-type Reference interface {
-	// HasDigest returns whether the reference has a verifiable
-	// content addressable reference which may be considered secure.
-	HasDigest() bool
-
-	// ImageName returns an image name for the given repository
-	ImageName(string) string
-
-	// Returns a string representation of the reference
-	String() string
-}
-
-type tagReference struct {
-	tag string
-}
-
-func (tr tagReference) HasDigest() bool {
-	return false
-}
-
-func (tr tagReference) ImageName(repo string) string {
-	return repo + ":" + tr.tag
-}
-
-func (tr tagReference) String() string {
-	return tr.tag
-}
-
-type digestReference struct {
-	digest digest.Digest
-}
-
-func (dr digestReference) HasDigest() bool {
-	return true
-}
-
-func (dr digestReference) ImageName(repo string) string {
-	return repo + "@" + dr.String()
-}
-
-func (dr digestReference) String() string {
-	return dr.digest.String()
-}
-
-// ParseReference parses a reference into either a digest or tag reference
-func ParseReference(ref string) Reference {
-	if strings.Contains(ref, ":") {
-		dgst, err := digest.ParseDigest(ref)
-		if err == nil {
-			return digestReference{digest: dgst}
-		}
-	}
-	return tagReference{tag: ref}
-}
-
-// DigestReference creates a digest reference using a digest
-func DigestReference(dgst digest.Digest) Reference {
-	return digestReference{digest: dgst}
-}