DockerCLI/cli/manifest/store/store.go

180 lines
5.1 KiB
Go

package store
import (
"encoding/json"
"fmt"
"os"
"path/filepath"
"strings"
"github.com/docker/cli/cli/manifest/types"
"github.com/docker/distribution/manifest/manifestlist"
"github.com/docker/distribution/reference"
"github.com/opencontainers/go-digest"
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/pkg/errors"
)
// Store manages local storage of image distribution manifests
type Store interface {
Remove(listRef reference.Reference) error
Get(listRef reference.Reference, manifest reference.Reference) (types.ImageManifest, error)
GetList(listRef reference.Reference) ([]types.ImageManifest, error)
Save(listRef reference.Reference, manifest reference.Reference, image types.ImageManifest) error
}
// fsStore manages manifest files stored on the local filesystem
type fsStore struct {
root string
}
// NewStore returns a new store for a local file path
func NewStore(root string) Store {
return &fsStore{root: root}
}
// Remove a manifest list from local storage
func (s *fsStore) Remove(listRef reference.Reference) error {
path := filepath.Join(s.root, makeFilesafeName(listRef.String()))
return os.RemoveAll(path)
}
// Get returns the local manifest
func (s *fsStore) Get(listRef reference.Reference, manifest reference.Reference) (types.ImageManifest, error) {
filename := manifestToFilename(s.root, listRef.String(), manifest.String())
return s.getFromFilename(manifest, filename)
}
func (s *fsStore) getFromFilename(ref reference.Reference, filename string) (types.ImageManifest, error) {
bytes, err := os.ReadFile(filename)
switch {
case os.IsNotExist(err):
return types.ImageManifest{}, newNotFoundError(ref.String())
case err != nil:
return types.ImageManifest{}, err
}
var manifestInfo struct {
types.ImageManifest
// Deprecated Fields, replaced by Descriptor
Digest digest.Digest
Platform *manifestlist.PlatformSpec
}
if err := json.Unmarshal(bytes, &manifestInfo); err != nil {
return types.ImageManifest{}, err
}
// Compatibility with image manifests created before
// descriptor, newer versions omit Digest and Platform
if manifestInfo.Digest != "" {
mediaType, raw, err := manifestInfo.Payload()
if err != nil {
return types.ImageManifest{}, err
}
if dgst := digest.FromBytes(raw); dgst != manifestInfo.Digest {
return types.ImageManifest{}, errors.Errorf("invalid manifest file %v: image manifest digest mismatch (%v != %v)", filename, manifestInfo.Digest, dgst)
}
manifestInfo.ImageManifest.Descriptor = ocispec.Descriptor{
Digest: manifestInfo.Digest,
Size: int64(len(raw)),
MediaType: mediaType,
Platform: types.OCIPlatform(manifestInfo.Platform),
}
}
return manifestInfo.ImageManifest, nil
}
// GetList returns all the local manifests for a transaction
func (s *fsStore) GetList(listRef reference.Reference) ([]types.ImageManifest, error) {
filenames, err := s.listManifests(listRef.String())
switch {
case err != nil:
return nil, err
case filenames == nil:
return nil, newNotFoundError(listRef.String())
}
manifests := []types.ImageManifest{}
for _, filename := range filenames {
filename = filepath.Join(s.root, makeFilesafeName(listRef.String()), filename)
manifest, err := s.getFromFilename(listRef, filename)
if err != nil {
return nil, err
}
manifests = append(manifests, manifest)
}
return manifests, nil
}
// listManifests stored in a transaction
func (s *fsStore) listManifests(transaction string) ([]string, error) {
transactionDir := filepath.Join(s.root, makeFilesafeName(transaction))
fileInfos, err := os.ReadDir(transactionDir)
switch {
case os.IsNotExist(err):
return nil, nil
case err != nil:
return nil, err
}
filenames := make([]string, 0, len(fileInfos))
for _, info := range fileInfos {
filenames = append(filenames, info.Name())
}
return filenames, nil
}
// Save a manifest as part of a local manifest list
func (s *fsStore) Save(listRef reference.Reference, manifest reference.Reference, image types.ImageManifest) error {
if err := s.createManifestListDirectory(listRef.String()); err != nil {
return err
}
filename := manifestToFilename(s.root, listRef.String(), manifest.String())
bytes, err := json.Marshal(image)
if err != nil {
return err
}
return os.WriteFile(filename, bytes, 0644)
}
func (s *fsStore) createManifestListDirectory(transaction string) error {
path := filepath.Join(s.root, makeFilesafeName(transaction))
return os.MkdirAll(path, 0755)
}
func manifestToFilename(root, manifestList, manifest string) string {
return filepath.Join(root, makeFilesafeName(manifestList), makeFilesafeName(manifest))
}
func makeFilesafeName(ref string) string {
fileName := strings.Replace(ref, ":", "-", -1)
return strings.Replace(fileName, "/", "_", -1)
}
type notFoundError struct {
object string
}
func newNotFoundError(ref string) *notFoundError {
return &notFoundError{object: ref}
}
func (n *notFoundError) Error() string {
return fmt.Sprintf("No such manifest: %s", n.object)
}
// NotFound interface
func (n *notFoundError) NotFound() {}
// IsNotFound returns true if the error is a not found error
func IsNotFound(err error) bool {
_, ok := err.(notFound)
return ok
}
type notFound interface {
NotFound()
}