package distribution import ( "bufio" "compress/gzip" "fmt" "io" "github.com/Sirupsen/logrus" "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" "github.com/docker/docker/reference" "github.com/docker/docker/registry" "github.com/docker/engine-api/types" "github.com/docker/libtrust" "golang.org/x/net/context" ) // ImagePushConfig stores push configuration. type ImagePushConfig struct { // MetaHeaders store HTTP headers with metadata about the image // (DockerHeaders with prefix X-Meta- in the request). 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 push // 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 // LayerStore manages layers. LayerStore layer.Store // ImageStore manages images. ImageStore image.Store // ReferenceStore manages tags. ReferenceStore reference.Store // 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 } // Pusher is an interface that abstracts pushing for different API versions. type Pusher interface { // Push tries to push the image configured at the creation of Pusher. // Push returns an error if any, as well as a boolean that determines whether to retry Push on the next configured endpoint. // // TODO(tiborvass): have Push() take a reference to repository + tag, so that the pusher itself is repository-agnostic. Push(ctx context.Context) error } const compressionBufSize = 32768 // NewPusher creates a new Pusher interface that will push to either a v1 or v2 // registry. The endpoint argument contains a Version field that determines // whether a v1 or v2 pusher will be created. The other parameters are passed // through to the underlying pusher implementation for use during the actual // push operation. func NewPusher(ref reference.Named, endpoint registry.APIEndpoint, repoInfo *registry.RepositoryInfo, imagePushConfig *ImagePushConfig) (Pusher, error) { switch endpoint.Version { case registry.APIVersion2: return &v2Pusher{ v2MetadataService: metadata.NewV2MetadataService(imagePushConfig.MetadataStore), ref: ref, endpoint: endpoint, repoInfo: repoInfo, config: imagePushConfig, }, nil case registry.APIVersion1: return &v1Pusher{ v1IDService: metadata.NewV1IDService(imagePushConfig.MetadataStore), ref: ref, endpoint: endpoint, repoInfo: repoInfo, config: imagePushConfig, }, nil } return nil, fmt.Errorf("unknown version %d for registry %s", endpoint.Version, endpoint.URL) } // Push initiates a push operation on the repository named localName. // ref is the specific variant of the image to be pushed. // If no tag is provided, all tags will be pushed. func Push(ctx context.Context, ref reference.Named, imagePushConfig *ImagePushConfig) error { // FIXME: Allow to interrupt current push when new push of same image is done. // Resolve the Repository name from fqn to RepositoryInfo repoInfo, err := imagePushConfig.RegistryService.ResolveRepository(ref) if err != nil { return err } endpoints, err := imagePushConfig.RegistryService.LookupPushEndpoints(repoInfo) if err != nil { return err } progress.Messagef(imagePushConfig.ProgressOutput, "", "The push refers to a repository [%s]", repoInfo.FullName()) associations := imagePushConfig.ReferenceStore.ReferencesByName(repoInfo) if len(associations) == 0 { return fmt.Errorf("Repository does not exist: %s", repoInfo.Name()) } var ( lastErr error // confirmedV2 is set to true if a push attempt managed to // confirm that it was talking to a v2 registry. This will // prevent fallback to the v1 protocol. confirmedV2 bool ) for _, endpoint := range endpoints { if confirmedV2 && endpoint.Version == registry.APIVersion1 { logrus.Debugf("Skipping v1 endpoint %s because v2 registry was detected", endpoint.URL) continue } logrus.Debugf("Trying to push %s to %s %s", repoInfo.FullName(), endpoint.URL, endpoint.Version) pusher, err := NewPusher(ref, endpoint, repoInfo, imagePushConfig) if err != nil { lastErr = err continue } if err := pusher.Push(ctx); err != nil { // Was this push cancelled? If so, don't try to fall // back. select { case <-ctx.Done(): default: if fallbackErr, ok := err.(fallbackError); ok { confirmedV2 = confirmedV2 || fallbackErr.confirmedV2 err = fallbackErr.err lastErr = err continue } } logrus.Debugf("Not continuing with error: %v", err) return err } imagePushConfig.ImageEventLogger(ref.String(), repoInfo.Name(), "push") return nil } if lastErr == nil { lastErr = fmt.Errorf("no endpoints found for %s", repoInfo.FullName()) } return lastErr } // compress returns an io.ReadCloser which will supply a compressed version of // the provided Reader. The caller must close the ReadCloser after reading the // compressed data. // // Note that this function returns a reader instead of taking a writer as an // argument so that it can be used with httpBlobWriter's ReadFrom method. // Using httpBlobWriter's Write method would send a PATCH request for every // Write call. func compress(in io.Reader) io.ReadCloser { pipeReader, pipeWriter := io.Pipe() // Use a bufio.Writer to avoid excessive chunking in HTTP request. bufWriter := bufio.NewWriterSize(pipeWriter, compressionBufSize) compressor := gzip.NewWriter(bufWriter) go func() { _, err := io.Copy(compressor, in) if err == nil { err = compressor.Close() } if err == nil { err = bufWriter.Flush() } if err != nil { pipeWriter.CloseWithError(err) } else { pipeWriter.Close() } }() return pipeReader }