feat: add resolve command

cmd/oras/root/cmd.go

@@ -34,6 +34,7 @@ func New() *cobra.Command {
 		logoutCmd(),
 		versionCmd(),
 		discoverCmd(),
+		resolveCmd(),
 		copyCmd(),
 		tagCmd(),
 		attachCmd(),

cmd/oras/root/resolve.go

@@ -0,0 +1,86 @@
+/*
+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 root
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"oras.land/oras-go/v2"
+	"oras.land/oras/cmd/oras/internal/option"
+)
+
+type resolveOptions struct {
+	option.Common
+	option.Platform
+	option.Target
+
+	FullRef bool
+}
+
+func resolveCmd() *cobra.Command {
+	var opts resolveOptions
+
+	cmd := &cobra.Command{
+		Use:   "resolve [flags] <name>{:<tag>|@<digest>}",
+		Short: "[Experimental] Resolves digest of the target artifact",
+		Long: `[Experimental] Resolves digest of the target artifact
+
+Example - Resolve digest of the target artifact:
+  oras resolve localhost:5000/hello-world:v1
+`,
+		Args:    cobra.ExactArgs(1),
+		Aliases: []string{"digest"},
+		PreRunE: func(cmd *cobra.Command, args []string) error {
+			opts.RawReference = args[0]
+			return option.Parse(&opts)
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return runResolve(cmd.Context(), opts)
+		},
+	}
+
+	cmd.Flags().BoolVarP(&opts.FullRef, "full-reference", "l", false, "print the full artifact reference with digest")
+	option.ApplyFlags(&opts, cmd.Flags())
+	return cmd
+}
+
+func runResolve(ctx context.Context, opts resolveOptions) error {
+	ctx, logger := opts.WithContext(ctx)
+	repo, err := opts.NewReadonlyTarget(ctx, opts.Common, logger)
+	if err != nil {
+		return err
+	}
+	if err := opts.EnsureReferenceNotEmpty(); err != nil {
+		return err
+	}
+	resolveOpts := oras.DefaultResolveOptions
+	resolveOpts.TargetPlatform = opts.Platform.Platform
+	desc, err := oras.Resolve(ctx, repo, opts.Reference, resolveOpts)
+
+	if err != nil {
+		return fmt.Errorf("failed to resolve digest: %w", err)
+	}
+
+	if opts.FullRef {
+		fmt.Printf("%s@%s\n", opts.Path, desc.Digest)
+	} else {
+		fmt.Println(desc.Digest.String())
+	}
+
+	return nil
+}

test/e2e/internal/utils/testdata.go

@@ -22,6 +22,7 @@ const (
 	BlobRepo     = "command/blobs"
 	ArtifactRepo = "command/artifacts"
 	Namespace    = "command"
+	InvalidRepo  = "INVALID"
 	// env
 	RegHostKey         = "ORAS_REGISTRY_HOST"
 	FallbackRegHostKey = "ORAS_REGISTRY_FALLBACK_HOST"

test/e2e/suite/command/resolve.go

@@ -0,0 +1,58 @@
+/*
+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 command
+
+import (
+	"fmt"
+	"strings"
+
+	. "github.com/onsi/ginkgo/v2"
+	"github.com/onsi/gomega"
+	"github.com/onsi/gomega/gbytes"
+	"oras.land/oras/test/e2e/internal/testdata/multi_arch"
+	. "oras.land/oras/test/e2e/internal/utils"
+)
+
+var _ = Describe("ORAS beginners:", func() {
+	When("running resolve command", func() {
+		It("should fail when no manifest reference provided", func() {
+			ORAS("resolve").ExpectFailure().MatchErrKeyWords("Error:").Exec()
+		})
+		It("should fail when repo is invalid", func() {
+			ORAS("resolve", fmt.Sprintf("%s/%s", ZOTHost, InvalidRepo)).ExpectFailure().MatchErrKeyWords("Error:", fmt.Sprintf("invalid reference: invalid repository %q", InvalidRepo)).Exec()
+		})
+		It("should fail when no tag or digest provided", func() {
+			ORAS("resolve", RegistryRef(ZOTHost, ImageRepo, "")).ExpectFailure().MatchErrKeyWords("Error:", "no tag or digest when expecting <name:tag|name@digest>").Exec()
+		})
+		It("should fail when provided manifest reference is not found", func() {
+			ORAS("resolve", RegistryRef(ZOTHost, ImageRepo, "i-dont-think-this-tag-exists")).ExpectFailure().MatchErrKeyWords("Error: failed to resolve digest:", "not found").Exec()
+		})
+		It("should resolve with just digest", func() {
+			out := ORAS("resolve", RegistryRef(ZOTHost, ImageRepo, multi_arch.Digest)).Exec().Out
+			outString := string(out.Contents())
+			outString = strings.TrimSpace(outString)
+			gomega.Expect(outString).To(gomega.Equal(multi_arch.Digest))
+		})
+		It("should resolve with a fully qualified reference", func() {
+			out := ORAS("digest", "-l", RegistryRef(ZOTHost, ImageRepo, multi_arch.Tag)).Exec().Out
+			gomega.Expect(out).To(gbytes.Say(fmt.Sprintf("%s/%s@%s", ZOTHost, ImageRepo, multi_arch.Digest)))
+		})
+		It("should resolve with a fully qualified reference for a platform", func() {
+			out := ORAS("resolve", "--full-reference", "--platform", "linux/amd64", RegistryRef(ZOTHost, ImageRepo, multi_arch.Tag)).Exec().Out
+			gomega.Expect(out).To(gbytes.Say(fmt.Sprintf("%s/%s@%s", ZOTHost, ImageRepo, multi_arch.LinuxAMD64.Digest)))
+		})
+	})
+})