distribution/storage/services.go
2014-12-23 17:13:02 -08:00

86 lines
2.8 KiB
Go

package storage
import (
"github.com/docker/distribution/digest"
"github.com/docker/distribution/storagedriver"
)
// Services provides various services with application-level operations for
// use across backend storage drivers.
type Services struct {
driver storagedriver.StorageDriver
pathMapper *pathMapper
layerUploadStore layerUploadStore
}
// NewServices creates a new Services object to access docker objects stored
// in the underlying driver.
func NewServices(driver storagedriver.StorageDriver) *Services {
layerUploadStore, err := newTemporaryLocalFSLayerUploadStore()
if err != nil {
// TODO(stevvooe): This failure needs to be understood in the context
// of the lifecycle of the services object, which is uncertain at this
// point.
panic("unable to allocate layerUploadStore: " + err.Error())
}
return &Services{
driver: driver,
pathMapper: &pathMapper{
// TODO(sday): This should be configurable.
root: "/docker/registry/",
version: storagePathVersion,
},
layerUploadStore: layerUploadStore,
}
}
// Layers returns an instance of the LayerService. Instantiation is cheap and
// may be context sensitive in the future. The instance should be used similar
// to a request local.
func (ss *Services) Layers() LayerService {
return &layerStore{driver: ss.driver, pathMapper: ss.pathMapper, uploadStore: ss.layerUploadStore}
}
// Manifests returns an instance of ManifestService. Instantiation is cheap and
// may be context sensitive in the future. The instance should be used similar
// to a request local.
func (ss *Services) Manifests() ManifestService {
return &manifestStore{driver: ss.driver, pathMapper: ss.pathMapper, layerService: ss.Layers()}
}
// ManifestService provides operations on image manifests.
type ManifestService interface {
// Tags lists the tags under the named repository.
Tags(name string) ([]string, error)
// Exists returns true if the layer exists.
Exists(name, tag string) (bool, error)
// Get retrieves the named manifest, if it exists.
Get(name, tag string) (*SignedManifest, error)
// Put creates or updates the named manifest.
Put(name, tag string, manifest *SignedManifest) error
// Delete removes the named manifest, if it exists.
Delete(name, tag string) error
}
// LayerService provides operations on layer files in a backend storage.
type LayerService interface {
// Exists returns true if the layer exists.
Exists(name string, digest digest.Digest) (bool, error)
// Fetch the layer identifed by TarSum.
Fetch(name string, digest digest.Digest) (Layer, error)
// Upload begins a layer upload to repository identified by name,
// returning a handle.
Upload(name string) (LayerUpload, error)
// Resume continues an in progress layer upload, returning the current
// state of the upload.
Resume(uuid string) (LayerUpload, error)
}