feat: support push a blob to a remote registry

cmd/oras/blob/cmd.go

@@ -27,6 +27,7 @@ func Cmd() *cobra.Command {
 
 	cmd.AddCommand(
 		fetchCmd(),
+		pushCmd(),
 	)
 	return cmd
 }

cmd/oras/blob/fetch.go

@@ -16,7 +16,6 @@ limitations under the License.
 package blob
 
 import (
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -150,7 +149,7 @@ func fetchBlob(opts fetchBlobOptions) (fetchErr error) {
 
 	// outputs blob's descriptor if `--descriptor` is used
 	if opts.OutputDescriptor {
-		descJSON, err := json.Marshal(desc)
+		descJSON, err := opts.Marshal(desc)
 		if err != nil {
 			return err
 		}

cmd/oras/blob/push.go

@@ -0,0 +1,146 @@
+/*
+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 blob
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/spf13/cobra"
+	"oras.land/oras/cmd/oras/internal/display"
+	"oras.land/oras/cmd/oras/internal/option"
+	"oras.land/oras/internal/file"
+)
+
+type pushBlobOptions struct {
+	option.Common
+	option.Descriptor
+	option.Pretty
+	option.Remote
+
+	fileRef   string
+	mediaType string
+	size      int64
+	targetRef string
+}
+
+func pushCmd() *cobra.Command {
+	var opts pushBlobOptions
+	cmd := &cobra.Command{
+		Use:   "push [flags] name[@digest] file",
+		Short: "[Preview] Push a blob to a remote registry",
+		Long: `[Preview] Push a blob to a remote registry
+
+** This command is in preview and under development. **
+
+Example - Push blob "hi.txt":
+  oras blob push localhost:5000/hello hi.txt
+
+Example - Push blob "hi.txt" with the specific digest:
+  oras blob push localhost:5000/hello@sha256:9a201d228ebd966211f7d1131be19f152be428bd373a92071c71d8deaf83b3e5 hi.txt
+
+Example - Push blob from stdin with blob size and digest:
+  oras blob push --size 12 localhost:5000/hello@sha256:9a201d228ebd966211f7d1131be19f152be428bd373a92071c71d8deaf83b3e5 -
+
+Example - Push blob "hi.txt" and output the descriptor:
+  oras blob push --descriptor localhost:5000/hello hi.txt
+
+Example - Push blob "hi.txt" with the specific returned media type in the descriptor:
+  oras blob push --media-type application/vnd.oci.image.config.v1+json --descriptor localhost:5000/hello hi.txt
+
+Example - Push blob "hi.txt" and output the prettified descriptor:
+  oras blob push --descriptor --pretty localhost:5000/hello hi.txt
+
+Example - Push blob without TLS:
+  oras blob push --insecure localhost:5000/hello hi.txt
+`,
+		Args: cobra.ExactArgs(2),
+		PreRunE: func(cmd *cobra.Command, args []string) error {
+			opts.targetRef = args[0]
+			opts.fileRef = args[1]
+			if opts.fileRef == "-" {
+				if opts.PasswordFromStdin {
+					return errors.New("`-` read file from input and `--password-stdin` read password from input cannot be both used")
+				}
+				if opts.size < 0 {
+					return errors.New("`--size` must be provided if the blob is read from stdin")
+				}
+			}
+			return opts.ReadPassword()
+		},
+		RunE: func(cmd *cobra.Command, args []string) error {
+			return pushBlob(opts)
+		},
+	}
+
+	cmd.Flags().Int64VarP(&opts.size, "size", "", -1, "provide the blob size")
+	cmd.Flags().StringVarP(&opts.mediaType, "media-type", "", ocispec.MediaTypeImageLayer, "specify the returned media type in the descriptor if `--descriptor` is used")
+	option.ApplyFlags(&opts, cmd.Flags())
+	return cmd
+}
+
+func pushBlob(opts pushBlobOptions) (err error) {
+	ctx, _ := opts.SetLoggerLevel()
+
+	repo, err := opts.NewRepository(opts.targetRef, opts.Common)
+	if err != nil {
+		return err
+	}
+
+	// prepare blob content
+	desc, rc, err := file.PrepareContent(opts.fileRef, opts.mediaType, repo.Reference.Reference, opts.size)
+	if err != nil {
+		return err
+	}
+	defer rc.Close()
+
+	exists, err := repo.Exists(ctx, desc)
+	if err != nil {
+		return err
+	}
+	verbose := opts.Verbose && !opts.OutputDescriptor
+	if exists {
+		if err := display.PrintStatus(desc, "Exists", verbose); err != nil {
+			return err
+		}
+	} else {
+		if err := display.PrintStatus(desc, "Uploading", verbose); err != nil {
+			return err
+		}
+		if err = repo.Push(ctx, desc, rc); err != nil {
+			return err
+		}
+		if err := display.PrintStatus(desc, "Uploaded ", verbose); err != nil {
+			return err
+		}
+	}
+
+	// outputs blob's descriptor
+	if opts.OutputDescriptor {
+		descJSON, err := opts.Marshal(desc)
+		if err != nil {
+			return err
+		}
+		return opts.Output(os.Stdout, descJSON)
+	}
+
+	fmt.Println("Pushed", opts.targetRef)
+	fmt.Println("Digest:", desc.Digest)
+
+	return nil
+}

cmd/oras/file.go

@@ -28,11 +28,13 @@ func loadFiles(ctx context.Context, store *file.Store, annotations map[string]ma
 	var files []ocispec.Descriptor
 	for _, fileRef := range fileRefs {
 		filename, mediaType := parseFileReference(fileRef, "")
+
+		// get shortest absolute path as unique name
 		name := filepath.Clean(filename)
 		if !filepath.IsAbs(name) {
-			// convert to slash-separated path unless it is absolute path
 			name = filepath.ToSlash(name)
 		}
+
 		if verbose {
 			fmt.Println("Preparing", name)
 		}

internal/file/file.go

@@ -0,0 +1,96 @@
+/*
+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 file
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+
+	digest "github.com/opencontainers/go-digest"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+)
+
+// PrepareContent prepares the content descriptor from the file path or stdin.
+// Use the input digest and size if they are provided. Will return error if the
+// content is from stdin but the content digest and size are missing.
+func PrepareContent(path string, mediaType string, dgstStr string, size int64) (desc ocispec.Descriptor, rc io.ReadCloser, prepareErr error) {
+	if path == "" {
+		return ocispec.Descriptor{}, nil, errors.New("missing file name")
+	}
+
+	// validate digest
+	var dgst digest.Digest
+	if dgstStr != "" {
+		var err error
+		dgst, err = digest.Parse(dgstStr)
+		if err != nil {
+			return ocispec.Descriptor{}, nil, fmt.Errorf("invalid digest %s: %w", dgstStr, err)
+		}
+	}
+
+	// prepares the content descriptor from stdin
+	if path == "-" {
+		// throw err if size or digest is not provided.
+		if size < 0 {
+			return ocispec.Descriptor{}, nil, errors.New("content size must be provided if it is read from stdin")
+		}
+		if dgst == "" {
+			return ocispec.Descriptor{}, nil, errors.New("content digest must be provided if it is read from stdin")
+		}
+		return ocispec.Descriptor{
+			MediaType: mediaType,
+			Digest:    dgst,
+			Size:      size,
+		}, os.Stdin, nil
+	}
+
+	file, err := os.Open(path)
+	if err != nil {
+		return ocispec.Descriptor{}, nil, fmt.Errorf("failed to open %s: %w", path, err)
+	}
+	defer func() {
+		if prepareErr != nil {
+			file.Close()
+		}
+	}()
+
+	fi, err := file.Stat()
+	if err != nil {
+		return ocispec.Descriptor{}, nil, fmt.Errorf("failed to stat %s: %w", path, err)
+	}
+	actualSize := fi.Size()
+	if size >= 0 && size != actualSize {
+		return ocispec.Descriptor{}, nil, fmt.Errorf("input size %d does not match the actual content size %d", size, actualSize)
+	}
+
+	if dgst == "" {
+		dgst, err = digest.FromReader(file)
+		if err != nil {
+			return ocispec.Descriptor{}, nil, err
+		}
+		if _, err = file.Seek(0, io.SeekStart); err != nil {
+			return ocispec.Descriptor{}, nil, err
+		}
+	}
+
+	return ocispec.Descriptor{
+		MediaType: mediaType,
+		Digest:    dgst,
+		Size:      actualSize,
+	}, file, nil
+}