registry

type BlobStore interface {
	content.Storage
	content.Deleter
	content.Resolver
	ReferenceFetcher
}

type ManifestStore interface {
	BlobStore
	content.Tagger
	ReferencePusher
}

type Mounter interface {
	// Mount makes the blob with the given descriptor in fromRepo
	// available in the repository signified by the receiver.
	Mount(ctx context.Context,
		desc ocispec.Descriptor,
		fromRepo string,
		getContent func() (io.ReadCloser, error),
	) error
}

type Reference struct {
	// Registry is the name of the registry. It is usually the domain name of
	// the registry optionally with a port.
	Registry string

	// Repository is the name of the repository.
	Repository string

	// Reference is the reference of the object in the repository. This field
	// can take any one of the four valid forms (see ParseReference). In the
	// case where it's the empty string, it necessarily implies valid form D,
	// and where it is non-empty, then it is either a tag, or a digest
	// (implying one of valid forms A, B, or C).
	Reference string
}

type ReferenceFetcher interface {
	// FetchReference fetches the content identified by the reference.
	FetchReference(ctx context.Context, reference string) (ocispec.Descriptor, io.ReadCloser, error)
}

type ReferencePusher interface {
	// PushReference pushes the manifest with a reference tag.
	PushReference(ctx context.Context, expected ocispec.Descriptor, content io.Reader, reference string) error
}

type ReferrerLister interface {
	Referrers(ctx context.Context, desc ocispec.Descriptor, artifactType string, fn func(referrers []ocispec.Descriptor) error) error
}

type Registry interface {
	// Repositories lists the name of repositories available in the registry.
	// Since the returned repositories may be paginated by the underlying
	// implementation, a function should be passed in to process the paginated
	// repository list.
	// `last` argument is the `last` parameter when invoking the catalog API.
	// If `last` is NOT empty, the entries in the response start after the
	// repo specified by `last`. Otherwise, the response starts from the top
	// of the Repositories list.
	// Note: When implemented by a remote registry, the catalog API is called.
	// However, not all registries supports pagination or conforms the
	// specification.
	// Reference: https://docs.docker.com/registry/spec/api/#catalog
	// See also `Repositories()` in this package.
	Repositories(ctx context.Context, last string, fn func(repos []string) error) error

	// Repository returns a repository reference by the given name.
	Repository(ctx context.Context, name string) (Repository, error)
}

type Repository interface {
	content.Storage
	content.Deleter
	content.TagResolver
	ReferenceFetcher
	ReferencePusher
	ReferrerLister
	TagLister

	// Blobs provides access to the blob CAS only, which contains config blobs,
	// layers, and other generic blobs.
	Blobs() BlobStore

	// Manifests provides access to the manifest CAS only.
	Manifests() ManifestStore
}

type TagLister interface {
	// Tags lists the tags available in the repository.
	// Since the returned tag list may be paginated by the underlying
	// implementation, a function should be passed in to process the paginated
	// tag list.
	//
	// `last` argument is the `last` parameter when invoking the tags API.
	// If `last` is NOT empty, the entries in the response start after the
	// tag specified by `last`. Otherwise, the response starts from the top
	// of the Tags list.
	//
	// Note: When implemented by a remote registry, the tags API is called.
	// However, not all registries supports pagination or conforms the
	// specification.
	//
	// References:
	//   - https://github.com/opencontainers/distribution-spec/blob/v1.1.0/spec.md#content-discovery
	//   - https://docs.docker.com/registry/spec/api/#tags
	// See also `Tags()` in this package.
	Tags(ctx context.Context, last string, fn func(tags []string) error) error
}