package daemon // import "github.com/docker/docker/daemon" import ( "io" "runtime" "strings" dist "github.com/docker/distribution" "github.com/docker/distribution/reference" "github.com/docker/docker/api/types" "github.com/docker/docker/distribution" progressutils "github.com/docker/docker/distribution/utils" "github.com/docker/docker/errdefs" "github.com/docker/docker/pkg/progress" "github.com/docker/docker/registry" "github.com/opencontainers/go-digest" "golang.org/x/net/context" ) // PullImage initiates a pull operation. image is the repository name to pull, and // tag may be either empty, or indicate a specific tag to pull. func (daemon *Daemon) PullImage(ctx context.Context, image, tag, os string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error { // Special case: "pull -a" may send an image name with a // trailing :. This is ugly, but let's not break API // compatibility. image = strings.TrimSuffix(image, ":") ref, err := reference.ParseNormalizedNamed(image) if err != nil { return errdefs.InvalidParameter(err) } if tag != "" { // The "tag" could actually be a digest. var dgst digest.Digest dgst, err = digest.Parse(tag) if err == nil { ref, err = reference.WithDigest(reference.TrimNamed(ref), dgst) } else { ref, err = reference.WithTag(ref, tag) } if err != nil { return errdefs.InvalidParameter(err) } } return daemon.pullImageWithReference(ctx, ref, os, metaHeaders, authConfig, outStream) } func (daemon *Daemon) pullImageWithReference(ctx context.Context, ref reference.Named, os string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error { // Include a buffer so that slow client connections don't affect // transfer performance. progressChan := make(chan progress.Progress, 100) writesDone := make(chan struct{}) ctx, cancelFunc := context.WithCancel(ctx) go func() { progressutils.WriteDistributionProgress(cancelFunc, outStream, progressChan) close(writesDone) }() // Default to the host OS platform in case it hasn't been populated with an explicit value. if os == "" { os = runtime.GOOS } imagePullConfig := &distribution.ImagePullConfig{ Config: distribution.Config{ MetaHeaders: metaHeaders, AuthConfig: authConfig, ProgressOutput: progress.ChanOutput(progressChan), RegistryService: daemon.RegistryService, ImageEventLogger: daemon.LogImageEvent, MetadataStore: daemon.distributionMetadataStore, ImageStore: distribution.NewImageConfigStoreFromStore(daemon.imageStore), ReferenceStore: daemon.referenceStore, }, DownloadManager: daemon.downloadManager, Schema2Types: distribution.ImageTypes, OS: os, } err := distribution.Pull(ctx, ref, imagePullConfig) close(progressChan) <-writesDone return err } // GetRepository returns a repository from the registry. func (daemon *Daemon) GetRepository(ctx context.Context, ref reference.Named, authConfig *types.AuthConfig) (dist.Repository, bool, error) { // get repository info repoInfo, err := daemon.RegistryService.ResolveRepository(ref) if err != nil { return nil, false, err } // makes sure name is not empty or `scratch` if err := distribution.ValidateRepoName(repoInfo.Name); err != nil { return nil, false, errdefs.InvalidParameter(err) } // get endpoints endpoints, err := daemon.RegistryService.LookupPullEndpoints(reference.Domain(repoInfo.Name)) if err != nil { return nil, false, err } // retrieve repository var ( confirmedV2 bool repository dist.Repository lastError error ) for _, endpoint := range endpoints { if endpoint.Version == registry.APIVersion1 { continue } repository, confirmedV2, lastError = distribution.NewV2Repository(ctx, repoInfo, endpoint, nil, authConfig, "pull") if lastError == nil && confirmedV2 { break } } return repository, confirmedV2, lastError }