package store import ( "encoding/json" "fmt" "io/ioutil" "os" "path/filepath" "strings" "github.com/docker/cli/cli/manifest/types" "github.com/docker/distribution/reference" ) // 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 := ioutil.ReadFile(filename) switch { case os.IsNotExist(err): return types.ImageManifest{}, newNotFoundError(ref.String()) case err != nil: return types.ImageManifest{}, err } var manifestInfo types.ImageManifest return manifestInfo, json.Unmarshal(bytes, &manifestInfo) } // 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 := ioutil.ReadDir(transactionDir) switch { case os.IsNotExist(err): return nil, nil case err != nil: return nil, err } filenames := []string{} 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 ioutil.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 ¬FoundError{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() }