feat(oci-layout): support in oras cp

cmd/oras/cp.go

@@ -30,15 +30,12 @@ import (
 )
 
 type copyOptions struct {
-	src option.Remote
-	dst option.Remote
 	option.Common
 	option.Platform
-	recursive bool
+	option.BinaryTarget
 
+	recursive   bool
 	concurrency int
-	srcRef      string
-	dstRef      string
 	extraRefs   []string
 }
 
@@ -52,54 +49,62 @@ func copyCmd() *cobra.Command {
 
 ** This command is in preview and under development. **
 
-Example - Copy the artifact tagged with 'v1' from repository 'localhost:5000/net-monitor' to repository 'localhost:5000/net-monitor-copy' 
-  oras cp localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:v1
+Example - Copy an artifact between registries:
+  oras cp localhost:5000/net-monitor:v1 localhost:6000/net-monitor-copy:v1
 
-Example - Copy the artifact tagged with 'v1' and its referrers from repository 'localhost:5000/net-monitor' to 'localhost:5000/net-monitor-copy'
-  oras cp -r localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:v1
+Example - Download an artifact into an OCI layout folder:
+  oras cp --to-oci localhost:5000/net-monitor:v1 ./downloaded:v1
 
-Example - Copy the artifact tagged with 'v1' from repository 'localhost:5000/net-monitor' to 'localhost:5000/net-monitor-copy' with certain platform
-  oras cp --platform linux/arm/v5 localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:v1 
+Example - Upload an artifact from an OCI layout folder:
+  oras cp --from-oci ./to-upload:v1 localhost:5000/net-monitor:v1
 
-Example - Copy the artifact tagged with 'v1' from repository 'localhost:5000/net-monitor' to 'localhost:5000/net-monitor-copy' with multiple tags
-  oras cp localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:v1,tag2,tag3
+Example - Upload an artifact from an OCI layout tar archive:
+  oras cp --from-oci ./to-upload.tar:v1 localhost:5000/net-monitor:v1
 
-Example - Copy the artifact tagged with 'v1' from repository 'localhost:5000/net-monitor' to 'localhost:5000/net-monitor-copy' with multiple tags and concurrency level tuned
-  oras cp --concurrency 6 localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:v1,tag2,tag3
+Example - Copy an artifact and its referrers:
+  oras cp -r localhost:5000/net-monitor:v1 localhost:6000/net-monitor-copy:v1
+
+Example - Copy certain platform of an artifact:
+ oras cp --platform linux/arm/v5 localhost:5000/net-monitor:v1 localhost:6000/net-monitor-copy:v1
+
+Example - Copy an artifact with multiple tags:
+  oras cp localhost:5000/net-monitor:v1 localhost:6000/net-monitor-copy:tag1,tag2,tag3
+
+Example - Copy an artifact with multiple tags with concurrency tuned:
+  oras cp --concurrency 10 localhost:5000/net-monitor:v1 localhost:5000/net-monitor-copy:tag1,tag2,tag3
 `,
 		Args: cobra.ExactArgs(2),
 		PreRunE: func(cmd *cobra.Command, args []string) error {
+			opts.From.RawReference = args[0]
+			refs := strings.Split(args[1], ",")
+			opts.To.RawReference = refs[0]
+			opts.extraRefs = refs[1:]
 			return option.Parse(&opts)
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
-			opts.srcRef = args[0]
-			refs := strings.Split(args[1], ",")
-			opts.dstRef = refs[0]
-			opts.extraRefs = refs[1:]
 			return runCopy(opts)
 		},
 	}
-
 	cmd.Flags().BoolVarP(&opts.recursive, "recursive", "r", false, "recursively copy the artifact and its referrer artifacts")
-	opts.src.ApplyFlagsWithPrefix(cmd.Flags(), "from", "source")
-	opts.dst.ApplyFlagsWithPrefix(cmd.Flags(), "to", "destination")
 	cmd.Flags().IntVarP(&opts.concurrency, "concurrency", "", 3, "concurrency level")
 	option.ApplyFlags(&opts, cmd.Flags())
-
 	return cmd
 }
 
 func runCopy(opts copyOptions) error {
 	ctx, _ := opts.SetLoggerLevel()
 
 	// Prepare source
-	src, err := opts.src.NewRepository(opts.srcRef, opts.Common)
+	src, err := opts.From.NewReadonlyTarget(ctx, opts.Common)
 	if err != nil {
 		return err
 	}
+	if opts.From.TagOrDigest == "" {
+		return errors.NewErrInvalidReferenceStr(opts.From.RawReference)
+	}
 
 	// Prepare destination
-	dst, err := opts.dst.NewRepository(opts.dstRef, opts.Common)
+	dst, err := opts.To.NewTarget(opts.Common)
 	if err != nil {
 		return err
 	}
@@ -121,14 +126,10 @@ func runCopy(opts copyOptions) error {
 		return display.PrintStatus(desc, "Exists ", opts.Verbose)
 	}
 
-	if src.Reference.Reference == "" {
-		return errors.NewErrInvalidReference(src.Reference)
-	}
-
 	var desc ocispec.Descriptor
-	if ref := dst.Reference.Reference; ref == "" {
+	if ref := opts.To.TagOrDigest; ref == "" {
 		// push to the destination with digest only if no tag specified
-		desc, err = src.Resolve(ctx, src.Reference.Reference)
+		desc, err = src.Resolve(ctx, opts.From.TagOrDigest)
 		if err != nil {
 			return err
 		}
@@ -139,27 +140,27 @@ func runCopy(opts copyOptions) error {
 		}
 	} else {
 		if opts.recursive {
-			desc, err = oras.ExtendedCopy(ctx, src, opts.srcRef, dst, opts.dstRef, extendedCopyOptions)
+			desc, err = oras.ExtendedCopy(ctx, src, opts.From.TagOrDigest, dst, opts.To.TagOrDigest, extendedCopyOptions)
 		} else {
 			copyOptions := oras.CopyOptions{
 				CopyGraphOptions: extendedCopyOptions.CopyGraphOptions,
 			}
 			if opts.Platform.Platform != nil {
 				copyOptions.WithTargetPlatform(opts.Platform.Platform)
 			}
-			desc, err = oras.Copy(ctx, src, opts.srcRef, dst, opts.dstRef, copyOptions)
+			desc, err = oras.Copy(ctx, src, opts.From.TagOrDigest, dst, opts.To.TagOrDigest, copyOptions)
 		}
 	}
 	if err != nil {
 		return err
 	}
 
-	fmt.Println("Copied", opts.srcRef, "=>", opts.dstRef)
+	fmt.Println("Copied", opts.From.AnnotatedReference(), "=>", opts.To.AnnotatedReference())
 
 	if len(opts.extraRefs) != 0 {
 		tagNOpts := oras.DefaultTagNOptions
 		tagNOpts.Concurrency = opts.concurrency
-		if err = oras.TagN(ctx, &display.TagManifestStatusPrinter{Repository: dst}, opts.dstRef, opts.extraRefs, tagNOpts); err != nil {
+		if _, err = oras.TagN(ctx, display.NewTagManifestStatusPrinter(dst), opts.To.TagOrDigest, opts.extraRefs, tagNOpts); err != nil {
 			return err
 		}
 	}

cmd/oras/internal/display/print.go

@@ -22,8 +22,9 @@ import (
 	"sync"
 
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"oras.land/oras-go/v2"
 	"oras.land/oras-go/v2/content"
-	"oras.land/oras-go/v2/registry/remote"
+	"oras.land/oras-go/v2/registry"
 )
 
 var printLock sync.Mutex
@@ -74,14 +75,38 @@ func PrintSuccessorStatus(ctx context.Context, desc ocispec.Descriptor, status s
 	return nil
 }
 
-type TagManifestStatusPrinter struct {
-	*remote.Repository
+// NewTagManifestStatusPrinter creates a wrapper type for printing tag status.
+func NewTagManifestStatusPrinter(target oras.Target) oras.Target {
+	if repo, ok := target.(registry.Repository); ok {
+		return &tagManifestStatusForRepo{
+			Repository: repo,
+		}
+	}
+	return &tagManifestStatusForTarget{
+		Target: target,
+	}
+}
+
+type tagManifestStatusForRepo struct {
+	registry.Repository
 }
 
 // PushReference overrides Repository.PushReference method to print off which tag(s) were added successfully.
-func (p *TagManifestStatusPrinter) PushReference(ctx context.Context, expected ocispec.Descriptor, content io.Reader, reference string) error {
+func (p *tagManifestStatusForRepo) PushReference(ctx context.Context, expected ocispec.Descriptor, content io.Reader, reference string) error {
 	if err := p.Repository.PushReference(ctx, expected, content, reference); err != nil {
 		return err
 	}
 	return Print("Tagged", reference)
 }
+
+type tagManifestStatusForTarget struct {
+	oras.Target
+}
+
+// Tag tags a descriptor with a reference string.
+func (p *tagManifestStatusForTarget) Tag(ctx context.Context, desc ocispec.Descriptor, reference string) error {
+	if err := p.Target.Tag(ctx, desc, reference); err != nil {
+		return err
+	}
+	return Print("Tagged", reference)
+}

cmd/oras/internal/errors/errors.go

@@ -23,5 +23,10 @@ import (
 
 // NewErrInvalidReference creates a new error based on the reference string.
 func NewErrInvalidReference(ref registry.Reference) error {
+	return NewErrInvalidReferenceStr(ref.String())
+}
+
+// NewErrInvalidReferenceStr creates a new error based on the reference string.
+func NewErrInvalidReferenceStr(ref string) error {
 	return fmt.Errorf("%s: invalid image reference, expecting <name:tag|name@digest>", ref)
 }

cmd/oras/internal/option/target.go

@@ -0,0 +1,171 @@
+/*
+Copyright The ORAS Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package option
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/spf13/pflag"
+	"oras.land/oras-go/v2"
+	"oras.land/oras-go/v2/content/oci"
+	"oras.land/oras-go/v2/registry"
+)
+
+const (
+	TargetTypeRemote    = "registry"
+	TargetTypeOCILayout = "oci"
+)
+
+// Unary target option struct.
+type Target struct {
+	Remote
+	RawReference string
+	Type         string
+	TagOrDigest  string
+
+	isOCI bool
+}
+
+// ApplyFlags applies flags to a command flag set for unary target
+func (opts *Target) ApplyFlags(fs *pflag.FlagSet) {
+	opts.applyFlagsWithPrefix(fs, "", "")
+	opts.Remote.ApplyFlags(fs)
+}
+
+// AnnotatedReference returns full printable reference.
+func (opts *Target) AnnotatedReference() string {
+	return fmt.Sprintf("[%s] %s", opts.Type, opts.RawReference)
+}
+
+// applyFlagsWithPrefix applies flags to a command flag set with a prefix string.
+// Commonly used for non-unary remote targets.
+func (opts *Target) applyFlagsWithPrefix(fs *pflag.FlagSet, prefix, description string) {
+	var (
+		flagPrefix string
+		noteSuffix string
+	)
+	if prefix != "" {
+		flagPrefix = prefix + "-"
+		noteSuffix = description + " "
+	}
+	fs.BoolVarP(&opts.isOCI, flagPrefix+"oci", "", false, "Set "+noteSuffix+"target as an OCI-layout.")
+}
+
+// ApplyFlagsWithPrefix applies flags to a command flag set with a prefix string.
+// Commonly used for non-unary remote targets.
+func (opts *Target) ApplyFlagsWithPrefix(fs *pflag.FlagSet, prefix, description string) {
+	opts.applyFlagsWithPrefix(fs, prefix, description)
+	opts.Remote.ApplyFlagsWithPrefix(fs, prefix, description)
+}
+
+// Parse gets target options from user input.
+func (opts *Target) Parse() error {
+	switch {
+	case opts.isOCI:
+		opts.Type = TargetTypeOCILayout
+	default:
+		opts.Type = TargetTypeRemote
+	}
+	return nil
+}
+
+func parseOCILayoutReference(raw string) (string, string) {
+	var path, ref string
+	if idx := strings.LastIndex(raw, "@"); idx != -1 {
+		// `digest` found
+		path = raw[:idx]
+		ref = raw[idx+1:]
+	} else if idx = strings.LastIndex(raw, ":"); idx != -1 {
+		// `tag` found
+		path = raw[:idx]
+		ref = raw[idx+1:]
+	}
+	return path, ref
+}
+
+// NewTarget generates a new target based on opts.
+func (opts *Target) NewTarget(common Common) (graphTarget oras.GraphTarget, err error) {
+	switch opts.Type {
+	case TargetTypeOCILayout:
+		var path string
+		path, opts.TagOrDigest = parseOCILayoutReference(opts.RawReference)
+		graphTarget, err = oci.New(path)
+		return
+	case TargetTypeRemote:
+		repo, err := opts.NewRepository(opts.RawReference, common)
+		if err != nil {
+			return nil, err
+		}
+		opts.TagOrDigest = repo.Reference.Reference
+		return repo, nil
+	}
+	return nil, fmt.Errorf("unknown target type: %q", opts.Type)
+}
+
+// Read-only graph target with tag lister.
+type ReadOnlyGraphTagFinderTarget interface {
+	oras.ReadOnlyGraphTarget
+	registry.TagLister
+}
+
+// NewReadonlyTargets generates a new read only target based on opts.
+func (opts *Target) NewReadonlyTarget(ctx context.Context, common Common) (ReadOnlyGraphTagFinderTarget, error) {
+	switch opts.Type {
+	case TargetTypeOCILayout:
+		var path string
+		path, opts.TagOrDigest = parseOCILayoutReference(opts.RawReference)
+		info, err := os.Stat(path)
+		if err != nil {
+			return nil, err
+		}
+		if info.IsDir() {
+			return oci.NewFromFS(ctx, os.DirFS(path))
+		}
+		return oci.NewFromTar(ctx, path)
+	case TargetTypeRemote:
+		repo, err := opts.NewRepository(opts.RawReference, common)
+		if err != nil {
+			return nil, err
+		}
+		opts.TagOrDigest = repo.Reference.Reference
+		return repo, nil
+	}
+	return nil, fmt.Errorf("unknown target type: %q", opts.Type)
+}
+
+// Binary target option struct.
+type BinaryTarget struct {
+	From Target
+	To   Target
+}
+
+// ApplyFlagsWithPrefix applies flags to a command flag set with a prefix string.
+// Commonly used for non-unary remote targets.
+func (opts *BinaryTarget) ApplyFlags(fs *pflag.FlagSet) {
+	opts.From.ApplyFlagsWithPrefix(fs, "from", "source")
+	opts.To.ApplyFlagsWithPrefix(fs, "to", "destination")
+}
+
+// Parse parses user-provided flags and arguments into option struct.
+func (opts *BinaryTarget) Parse() error {
+	if err := opts.From.Parse(); err != nil {
+		return err
+	}
+	return opts.To.Parse()
+}