blob: f24678d0e27ca1460e32f7a5ce522495a5ce5527 [file] [log] [blame]
package distribution
import (
"encoding/json"
"fmt"
"io"
"runtime"
"github.com/docker/distribution"
"github.com/docker/distribution/manifest/schema2"
"github.com/docker/docker/api/types"
"github.com/docker/docker/distribution/metadata"
"github.com/docker/docker/distribution/xfer"
"github.com/docker/docker/image"
"github.com/docker/docker/layer"
"github.com/docker/docker/pkg/progress"
refstore "github.com/docker/docker/reference"
"github.com/docker/docker/registry"
"github.com/docker/libtrust"
"github.com/opencontainers/go-digest"
"golang.org/x/net/context"
)
// Config stores configuration for communicating
// with a registry.
type Config struct {
// MetaHeaders stores HTTP headers with metadata about the image
MetaHeaders map[string][]string
// AuthConfig holds authentication credentials for authenticating with
// the registry.
AuthConfig *types.AuthConfig
// ProgressOutput is the interface for showing the status of the pull
// operation.
ProgressOutput progress.Output
// RegistryService is the registry service to use for TLS configuration
// and endpoint lookup.
RegistryService registry.Service
// ImageEventLogger notifies events for a given image
ImageEventLogger func(id, name, action string)
// MetadataStore is the storage backend for distribution-specific
// metadata.
MetadataStore metadata.Store
// ImageStore manages images.
ImageStore ImageConfigStore
// ReferenceStore manages tags. This value is optional, when excluded
// content will not be tagged.
ReferenceStore refstore.Store
// RequireSchema2 ensures that only schema2 manifests are used.
RequireSchema2 bool
}
// ImagePullConfig stores pull configuration.
type ImagePullConfig struct {
Config
// DownloadManager manages concurrent pulls.
DownloadManager RootFSDownloadManager
// Schema2Types is the valid schema2 configuration types allowed
// by the pull operation.
Schema2Types []string
}
// ImagePushConfig stores push configuration.
type ImagePushConfig struct {
Config
// ConfigMediaType is the configuration media type for
// schema2 manifests.
ConfigMediaType string
// LayerStore manages layers.
LayerStore PushLayerProvider
// TrustKey is the private key for legacy signatures. This is typically
// an ephemeral key, since these signatures are no longer verified.
TrustKey libtrust.PrivateKey
// UploadManager dispatches uploads.
UploadManager *xfer.LayerUploadManager
}
// ImageConfigStore handles storing and getting image configurations
// by digest. Allows getting an image configurations rootfs from the
// configuration.
type ImageConfigStore interface {
Put([]byte) (digest.Digest, error)
Get(digest.Digest) ([]byte, error)
RootFSFromConfig([]byte) (*image.RootFS, error)
}
// PushLayerProvider provides layers to be pushed by ChainID.
type PushLayerProvider interface {
Get(layer.ChainID) (PushLayer, error)
}
// PushLayer is a pushable layer with metadata about the layer
// and access to the content of the layer.
type PushLayer interface {
ChainID() layer.ChainID
DiffID() layer.DiffID
Parent() PushLayer
Open() (io.ReadCloser, error)
Size() (int64, error)
MediaType() string
Release()
}
// RootFSDownloadManager handles downloading of the rootfs
type RootFSDownloadManager interface {
// Download downloads the layers into the given initial rootfs and
// returns the final rootfs.
// Given progress output to track download progress
// Returns function to release download resources
Download(ctx context.Context, initialRootFS image.RootFS, layers []xfer.DownloadDescriptor, progressOutput progress.Output) (image.RootFS, func(), error)
}
type imageConfigStore struct {
image.Store
}
// NewImageConfigStoreFromStore returns an ImageConfigStore backed
// by an image.Store for container images.
func NewImageConfigStoreFromStore(is image.Store) ImageConfigStore {
return &imageConfigStore{
Store: is,
}
}
func (s *imageConfigStore) Put(c []byte) (digest.Digest, error) {
id, err := s.Store.Create(c)
return digest.Digest(id), err
}
func (s *imageConfigStore) Get(d digest.Digest) ([]byte, error) {
img, err := s.Store.Get(image.IDFromDigest(d))
if err != nil {
return nil, err
}
return img.RawJSON(), nil
}
func (s *imageConfigStore) RootFSFromConfig(c []byte) (*image.RootFS, error) {
var unmarshalledConfig image.Image
if err := json.Unmarshal(c, &unmarshalledConfig); err != nil {
return nil, err
}
// fail immediately on Windows when downloading a non-Windows image
// and vice versa
if runtime.GOOS == "windows" && unmarshalledConfig.OS == "linux" {
return nil, fmt.Errorf("image operating system %q cannot be used on this platform", unmarshalledConfig.OS)
} else if runtime.GOOS != "windows" && unmarshalledConfig.OS == "windows" {
return nil, fmt.Errorf("image operating system %q cannot be used on this platform", unmarshalledConfig.OS)
}
return unmarshalledConfig.RootFS, nil
}
type storeLayerProvider struct {
ls layer.Store
}
// NewLayerProviderFromStore returns a layer provider backed by
// an instance of LayerStore. Only getting layers as gzipped
// tars is supported.
func NewLayerProviderFromStore(ls layer.Store) PushLayerProvider {
return &storeLayerProvider{
ls: ls,
}
}
func (p *storeLayerProvider) Get(lid layer.ChainID) (PushLayer, error) {
if lid == "" {
return &storeLayer{
Layer: layer.EmptyLayer,
}, nil
}
l, err := p.ls.Get(lid)
if err != nil {
return nil, err
}
sl := storeLayer{
Layer: l,
ls: p.ls,
}
if d, ok := l.(distribution.Describable); ok {
return &describableStoreLayer{
storeLayer: sl,
describable: d,
}, nil
}
return &sl, nil
}
type storeLayer struct {
layer.Layer
ls layer.Store
}
func (l *storeLayer) Parent() PushLayer {
p := l.Layer.Parent()
if p == nil {
return nil
}
sl := storeLayer{
Layer: p,
ls: l.ls,
}
if d, ok := p.(distribution.Describable); ok {
return &describableStoreLayer{
storeLayer: sl,
describable: d,
}
}
return &sl
}
func (l *storeLayer) Open() (io.ReadCloser, error) {
return l.Layer.TarStream()
}
func (l *storeLayer) Size() (int64, error) {
return l.Layer.DiffSize()
}
func (l *storeLayer) MediaType() string {
// layer store always returns uncompressed tars
return schema2.MediaTypeUncompressedLayer
}
func (l *storeLayer) Release() {
if l.ls != nil {
layer.ReleaseAndLog(l.ls, l.Layer)
}
}
type describableStoreLayer struct {
storeLayer
describable distribution.Describable
}
func (l *describableStoreLayer) Descriptor() distribution.Descriptor {
return l.describable.Descriptor()
}