Merge pull request #612 from stevvooe/simplify-resolution-flow
cmd/dist, remotes: simplify resolution flow
This commit is contained in:
commit
0e0ae74b82
6 changed files with 593 additions and 201 deletions
76
cmd/dist/fetch.go
vendored
76
cmd/dist/fetch.go
vendored
|
@ -45,9 +45,8 @@ Most of this is experimental and there are few leaps to make this work.`,
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Flags: []cli.Flag{},
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Flags: []cli.Flag{},
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Action: func(clicontext *cli.Context) error {
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Action: func(clicontext *cli.Context) error {
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var (
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var (
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ctx = background
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ctx = background
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locator = clicontext.Args().First()
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ref = clicontext.Args().First()
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object = clicontext.Args().Get(1)
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)
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)
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conn, err := connectGRPC(clicontext)
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conn, err := connectGRPC(clicontext)
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@ -59,11 +58,7 @@ Most of this is experimental and there are few leaps to make this work.`,
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if err != nil {
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if err != nil {
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return err
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return err
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}
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}
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ctx = withJobsContext(ctx)
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fetcher, err := resolver.Resolve(ctx, locator)
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if err != nil {
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return err
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}
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ingester := contentservice.NewIngesterFromClient(contentapi.NewContentClient(conn))
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ingester := contentservice.NewIngesterFromClient(contentapi.NewContentClient(conn))
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cs, err := resolveContentStore(clicontext)
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cs, err := resolveContentStore(clicontext)
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@ -73,10 +68,17 @@ Most of this is experimental and there are few leaps to make this work.`,
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eg, ctx := errgroup.WithContext(ctx)
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eg, ctx := errgroup.WithContext(ctx)
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ctx = withJobsContext(ctx)
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resolved := make(chan struct{})
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eg.Go(func() error {
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eg.Go(func() error {
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return fetchManifest(ctx, ingester, fetcher, object)
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addJob(ctx, ref)
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name, desc, fetcher, err := resolver.Resolve(ctx, ref)
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if err != nil {
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return err
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}
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log.G(ctx).WithField("image", name).Debug("fetching")
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close(resolved)
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return dispatch(ctx, ingester, fetcher, desc)
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})
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})
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errs := make(chan error)
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errs := make(chan error)
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@ -96,8 +98,7 @@ Most of this is experimental and there are few leaps to make this work.`,
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case <-ticker.C:
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case <-ticker.C:
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fw.Flush()
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fw.Flush()
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tw := tabwriter.NewWriter(fw, 1, 8, 1, '\t', 0)
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tw := tabwriter.NewWriter(fw, 1, 8, 1, ' ', 0)
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// fmt.Fprintln(tw, "REF\tSIZE\tAGE")
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var total int64
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var total int64
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js := getJobs(ctx)
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js := getJobs(ctx)
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@ -137,10 +138,20 @@ Most of this is experimental and there are few leaps to make this work.`,
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if _, ok := activeSeen[j]; ok {
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if _, ok := activeSeen[j]; ok {
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continue
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continue
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}
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}
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status := "done"
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if j == ref {
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select {
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case <-resolved:
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status = "resolved"
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default:
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status = "resolving"
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}
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}
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statuses[j] = statusInfo{
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statuses[j] = statusInfo{
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Ref: j,
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Ref: j,
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Status: "done", // for now!
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Status: status, // for now!
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}
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}
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}
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}
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@ -151,21 +162,27 @@ Most of this is experimental and there are few leaps to make this work.`,
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switch status.Status {
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switch status.Status {
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case "downloading":
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case "downloading":
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bar := progress.Bar(float64(status.Offset) / float64(status.Total))
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bar := progress.Bar(float64(status.Offset) / float64(status.Total))
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fmt.Fprintf(tw, "%s:\t%s\t%40r\t%8.8s/%s\n",
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fmt.Fprintf(tw, "%s:\t%s\t%40r\t%8.8s/%s\t\n",
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status.Ref,
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status.Ref,
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status.Status,
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status.Status,
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bar,
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bar,
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progress.Bytes(status.Offset), progress.Bytes(status.Total))
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progress.Bytes(status.Offset), progress.Bytes(status.Total))
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case "done":
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case "resolving":
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bar := progress.Bar(0.0)
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fmt.Fprintf(tw, "%s:\t%s\t%40r\t\n",
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status.Ref,
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status.Status,
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bar)
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default:
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bar := progress.Bar(1.0)
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bar := progress.Bar(1.0)
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fmt.Fprintf(tw, "%s:\t%s\t%40r\n",
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fmt.Fprintf(tw, "%s:\t%s\t%40r\t\n",
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status.Ref,
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status.Ref,
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status.Status,
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status.Status,
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bar)
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bar)
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}
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}
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}
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}
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fmt.Fprintf(tw, "elapsed: %-4.1fs\ttotal: %7.6v\t(%v)\n",
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fmt.Fprintf(tw, "elapsed: %-4.1fs\ttotal: %7.6v\t(%v)\t\n",
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time.Since(start).Seconds(),
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time.Since(start).Seconds(),
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// TODO(stevvooe): These calculations are actually way off.
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// TODO(stevvooe): These calculations are actually way off.
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// Need to account for previously downloaded data. These
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// Need to account for previously downloaded data. These
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@ -250,14 +267,11 @@ func (j *jobs) jobs() []string {
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return jobs
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return jobs
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}
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}
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func fetchManifest(ctx context.Context, ingester content.Ingester, fetcher remotes.Fetcher, object string, hints ...string) error {
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func fetchManifest(ctx context.Context, ingester content.Ingester, fetcher remotes.Fetcher, desc ocispec.Descriptor) error {
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const manifestMediaType = "application/vnd.docker.distribution.manifest.v2+json"
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ref := "manifest-" + desc.Digest.String()
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hints = append(hints, "mediatype:"+manifestMediaType)
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ref := "manifest-" + object
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addJob(ctx, ref)
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addJob(ctx, ref)
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rc, err := fetcher.Fetch(ctx, object, hints...)
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rc, err := fetcher.Fetch(ctx, desc)
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if err != nil {
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if err != nil {
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return err
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return err
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}
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}
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@ -291,18 +305,10 @@ func fetchManifest(ctx context.Context, ingester content.Ingester, fetcher remot
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}
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}
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func fetch(ctx context.Context, ingester content.Ingester, fetcher remotes.Fetcher, desc ocispec.Descriptor) error {
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func fetch(ctx context.Context, ingester content.Ingester, fetcher remotes.Fetcher, desc ocispec.Descriptor) error {
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var (
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ref := "fetch-" + desc.Digest.String()
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hints []string
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object = desc.Digest.String()
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)
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if desc.MediaType != "" {
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hints = append(hints, "mediatype:"+desc.MediaType)
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}
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ref := "fetch-" + object
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addJob(ctx, ref)
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addJob(ctx, ref)
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log.G(ctx).Debug("fetch")
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log.G(ctx).Debug("fetch")
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rc, err := fetcher.Fetch(ctx, object, hints...)
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rc, err := fetcher.Fetch(ctx, desc)
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if err != nil {
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if err != nil {
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log.G(ctx).WithError(err).Error("fetch error")
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log.G(ctx).WithError(err).Error("fetch error")
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return err
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return err
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@ -328,7 +334,7 @@ func dispatch(ctx context.Context, ingester content.Ingester, fetcher remotes.Fe
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switch desc.MediaType {
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switch desc.MediaType {
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case MediaTypeDockerSchema2Manifest, ocispec.MediaTypeImageManifest:
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case MediaTypeDockerSchema2Manifest, ocispec.MediaTypeImageManifest:
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eg.Go(func() error {
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eg.Go(func() error {
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return fetchManifest(ctx, ingester, fetcher, desc.Digest.String(), "mediatype:"+desc.MediaType)
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return fetchManifest(ctx, ingester, fetcher, desc)
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})
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})
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case MediaTypeDockerSchema2ManifestList, ocispec.MediaTypeImageIndex:
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case MediaTypeDockerSchema2ManifestList, ocispec.MediaTypeImageIndex:
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return fmt.Errorf("%v not yet supported", desc.MediaType)
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return fmt.Errorf("%v not yet supported", desc.MediaType)
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321
cmd/dist/fetchobject.go
vendored
321
cmd/dist/fetchobject.go
vendored
|
@ -10,10 +10,12 @@ import (
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"net/url"
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"net/url"
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"os"
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"os"
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"path"
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"path"
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"strconv"
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"strings"
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"strings"
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"github.com/Sirupsen/logrus"
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"github.com/Sirupsen/logrus"
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"github.com/docker/containerd/log"
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"github.com/docker/containerd/log"
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"github.com/docker/containerd/reference"
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"github.com/docker/containerd/remotes"
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"github.com/docker/containerd/remotes"
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digest "github.com/opencontainers/go-digest"
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digest "github.com/opencontainers/go-digest"
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ocispec "github.com/opencontainers/image-spec/specs-go/v1"
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ocispec "github.com/opencontainers/image-spec/specs-go/v1"
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@ -47,8 +49,7 @@ var fetchObjectCommand = cli.Command{
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var (
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var (
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ctx = background
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ctx = background
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timeout = context.Duration("timeout")
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timeout = context.Duration("timeout")
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locator = context.Args().First()
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ref = context.Args().First()
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args = context.Args().Tail()
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)
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)
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|
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if timeout > 0 {
|
if timeout > 0 {
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@ -57,35 +58,21 @@ var fetchObjectCommand = cli.Command{
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defer cancel()
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defer cancel()
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}
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}
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|
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if locator == "" {
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return errors.New("containerd: remote required")
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}
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|
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if len(args) < 1 {
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return errors.New("containerd: object required")
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}
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|
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object := args[0]
|
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hints := args[1:]
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|
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resolver, err := getResolver(ctx)
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resolver, err := getResolver(ctx)
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if err != nil {
|
if err != nil {
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return err
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return err
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}
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}
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|
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remote, err := resolver.Resolve(ctx, locator)
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ctx = log.WithLogger(ctx, log.G(ctx).WithField("ref", ref))
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|
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log.G(ctx).Infof("resolving")
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|
_, desc, fetcher, err := resolver.Resolve(ctx, ref)
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if err != nil {
|
if err != nil {
|
||||||
return err
|
return err
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||||||
}
|
}
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|
|
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ctx = log.WithLogger(ctx, log.G(ctx).WithFields(
|
|
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logrus.Fields{
|
|
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"remote": locator,
|
|
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"object": object,
|
|
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}))
|
|
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|
|
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log.G(ctx).Infof("fetching")
|
log.G(ctx).Infof("fetching")
|
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rc, err := remote.Fetch(ctx, object, hints...)
|
rc, err := fetcher.Fetch(ctx, desc)
|
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if err != nil {
|
if err != nil {
|
||||||
return err
|
return err
|
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}
|
}
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||||||
|
@ -99,91 +86,217 @@ var fetchObjectCommand = cli.Command{
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},
|
},
|
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}
|
}
|
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|
|
||||||
|
// getResolver prepares the resolver from the environment and options.
|
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func getResolver(ctx contextpkg.Context) (remotes.Resolver, error) {
|
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|
return newDockerResolver(), nil
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|
}
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|
|
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// NOTE(stevvooe): Most of the code below this point is prototype code to
|
// NOTE(stevvooe): Most of the code below this point is prototype code to
|
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// demonstrate a very simplified docker.io fetcher. We have a lot of hard coded
|
// demonstrate a very simplified docker.io fetcher. We have a lot of hard coded
|
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// values but we leave many of the details down to the fetcher, creating a lot
|
// values but we leave many of the details down to the fetcher, creating a lot
|
||||||
// of room for ways to fetch content.
|
// of room for ways to fetch content.
|
||||||
|
|
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// getResolver prepares the resolver from the environment and options.
|
type dockerFetcher struct {
|
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func getResolver(ctx contextpkg.Context) (remotes.Resolver, error) {
|
base url.URL
|
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return remotes.ResolverFunc(func(ctx contextpkg.Context, locator string) (remotes.Fetcher, error) {
|
token string
|
||||||
if !strings.HasPrefix(locator, "docker.io") && !strings.HasPrefix(locator, "localhost:5000") {
|
}
|
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return nil, errors.Errorf("unsupported locator: %q", locator)
|
|
||||||
}
|
|
||||||
|
|
||||||
var (
|
func (r *dockerFetcher) url(ps ...string) string {
|
||||||
base = url.URL{
|
url := r.base
|
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Scheme: "https",
|
url.Path = path.Join(url.Path, path.Join(ps...))
|
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Host: "registry-1.docker.io",
|
return url.String()
|
||||||
}
|
}
|
||||||
prefix = strings.TrimPrefix(locator, "docker.io/")
|
|
||||||
)
|
|
||||||
|
|
||||||
if strings.HasPrefix(locator, "localhost:5000") {
|
func (r *dockerFetcher) Fetch(ctx contextpkg.Context, desc ocispec.Descriptor) (io.ReadCloser, error) {
|
||||||
base.Scheme = "http"
|
ctx = log.WithLogger(ctx, log.G(ctx).WithFields(
|
||||||
base.Host = "localhost:5000"
|
logrus.Fields{
|
||||||
prefix = strings.TrimPrefix(locator, "localhost:5000/")
|
"base": r.base.String(),
|
||||||
}
|
"digest": desc.Digest,
|
||||||
|
},
|
||||||
|
))
|
||||||
|
|
||||||
token, err := getToken(ctx, "repository:"+prefix+":pull")
|
paths, err := getV2URLPaths(desc)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
for _, path := range paths {
|
||||||
|
u := r.url(path)
|
||||||
|
|
||||||
|
req, err := http.NewRequest(http.MethodGet, u, nil)
|
||||||
if err != nil {
|
if err != nil {
|
||||||
return nil, err
|
return nil, err
|
||||||
}
|
}
|
||||||
|
|
||||||
return remotes.FetcherFunc(func(ctx contextpkg.Context, object string, hints ...string) (io.ReadCloser, error) {
|
req.Header.Set("Accept", strings.Join([]string{desc.MediaType, `*`}, ", "))
|
||||||
ctx = log.WithLogger(ctx, log.G(ctx).WithFields(
|
resp, err := r.doRequest(ctx, req)
|
||||||
logrus.Fields{
|
if err != nil {
|
||||||
"prefix": prefix, // or repo?
|
return nil, err
|
||||||
"base": base.String(),
|
}
|
||||||
"hints": hints,
|
|
||||||
},
|
|
||||||
))
|
|
||||||
|
|
||||||
if _, err := digest.Parse(object); err != nil {
|
if resp.StatusCode > 299 {
|
||||||
// in this case, we are seeking a manifest by a tag. Let's add some hints.
|
if resp.StatusCode == http.StatusNotFound {
|
||||||
hints = append(hints, "mediatype:"+MediaTypeDockerSchema2Manifest)
|
continue // try one of the other urls.
|
||||||
hints = append(hints, "mediatype:"+MediaTypeDockerSchema2ManifestList)
|
|
||||||
hints = append(hints, "mediatype:"+ocispec.MediaTypeImageManifest)
|
|
||||||
hints = append(hints, "mediatype:"+ocispec.MediaTypeImageIndex)
|
|
||||||
}
|
}
|
||||||
|
resp.Body.Close()
|
||||||
|
return nil, errors.Errorf("unexpected status code %v: %v", u, resp.Status)
|
||||||
|
}
|
||||||
|
|
||||||
paths, err := getV2URLPaths(prefix, object, hints...)
|
return resp.Body, nil
|
||||||
if err != nil {
|
}
|
||||||
return nil, err
|
|
||||||
|
return nil, errors.New("not found")
|
||||||
|
}
|
||||||
|
|
||||||
|
func (r *dockerFetcher) doRequest(ctx contextpkg.Context, req *http.Request) (*http.Response, error) {
|
||||||
|
ctx = log.WithLogger(ctx, log.G(ctx).WithField("url", req.URL.String()))
|
||||||
|
log.G(ctx).WithField("request.headers", req.Header).Debug("fetch content")
|
||||||
|
if r.token != "" {
|
||||||
|
req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", r.token))
|
||||||
|
}
|
||||||
|
|
||||||
|
resp, err := ctxhttp.Do(ctx, http.DefaultClient, req)
|
||||||
|
if err != nil {
|
||||||
|
return nil, err
|
||||||
|
}
|
||||||
|
log.G(ctx).WithFields(logrus.Fields{
|
||||||
|
"status": resp.Status,
|
||||||
|
"response.headers": resp.Header,
|
||||||
|
}).Debug("fetch response received")
|
||||||
|
|
||||||
|
return resp, err
|
||||||
|
}
|
||||||
|
|
||||||
|
type dockerResolver struct{}
|
||||||
|
|
||||||
|
var _ remotes.Resolver = &dockerResolver{}
|
||||||
|
|
||||||
|
func newDockerResolver() remotes.Resolver {
|
||||||
|
return &dockerResolver{}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (r *dockerResolver) Resolve(ctx contextpkg.Context, ref string) (string, ocispec.Descriptor, remotes.Fetcher, error) {
|
||||||
|
refspec, err := reference.Parse(ref)
|
||||||
|
if err != nil {
|
||||||
|
return "", ocispec.Descriptor{}, nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
base url.URL
|
||||||
|
token string
|
||||||
|
)
|
||||||
|
|
||||||
|
switch refspec.Hostname() {
|
||||||
|
case "docker.io":
|
||||||
|
base.Scheme = "https"
|
||||||
|
base.Host = "registry-1.docker.io"
|
||||||
|
prefix := strings.TrimPrefix(refspec.Locator, "docker.io/")
|
||||||
|
base.Path = path.Join("/v2", prefix)
|
||||||
|
token, err = getToken(ctx, "repository:"+prefix+":pull")
|
||||||
|
if err != nil {
|
||||||
|
return "", ocispec.Descriptor{}, nil, err
|
||||||
|
}
|
||||||
|
case "localhost:5000":
|
||||||
|
base.Scheme = "http"
|
||||||
|
base.Host = "localhost:5000"
|
||||||
|
base.Path = path.Join("/v2", strings.TrimPrefix(refspec.Locator, "localhost:5000/"))
|
||||||
|
default:
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Errorf("unsupported locator: %q", refspec.Locator)
|
||||||
|
}
|
||||||
|
|
||||||
|
fetcher := &dockerFetcher{
|
||||||
|
base: base,
|
||||||
|
token: token,
|
||||||
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
urls []string
|
||||||
|
dgst = refspec.Digest()
|
||||||
|
)
|
||||||
|
|
||||||
|
if dgst != "" {
|
||||||
|
if err := dgst.Validate(); err != nil {
|
||||||
|
// need to fail here, since we can't actually resolve the invalid
|
||||||
|
// digest.
|
||||||
|
return "", ocispec.Descriptor{}, nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
// turns out, we have a valid digest, make a url.
|
||||||
|
urls = append(urls, fetcher.url("manifests", dgst.String()))
|
||||||
|
} else {
|
||||||
|
urls = append(urls, fetcher.url("manifests", refspec.Object))
|
||||||
|
}
|
||||||
|
|
||||||
|
// fallback to blobs on not found.
|
||||||
|
urls = append(urls, fetcher.url("blobs", dgst.String()))
|
||||||
|
|
||||||
|
for _, u := range urls {
|
||||||
|
req, err := http.NewRequest(http.MethodHead, u, nil)
|
||||||
|
if err != nil {
|
||||||
|
return "", ocispec.Descriptor{}, nil, err
|
||||||
|
}
|
||||||
|
|
||||||
|
// set headers for all the types we support for resolution.
|
||||||
|
req.Header.Set("Accept", strings.Join([]string{
|
||||||
|
MediaTypeDockerSchema2Manifest,
|
||||||
|
MediaTypeDockerSchema2ManifestList,
|
||||||
|
ocispec.MediaTypeImageManifest,
|
||||||
|
ocispec.MediaTypeImageIndex, "*"}, ", "))
|
||||||
|
|
||||||
|
log.G(ctx).Debug("resolving")
|
||||||
|
resp, err := fetcher.doRequest(ctx, req)
|
||||||
|
if err != nil {
|
||||||
|
return "", ocispec.Descriptor{}, nil, err
|
||||||
|
}
|
||||||
|
resp.Body.Close() // don't care about body contents.
|
||||||
|
|
||||||
|
if resp.StatusCode > 299 {
|
||||||
|
if resp.StatusCode == http.StatusNotFound {
|
||||||
|
continue
|
||||||
}
|
}
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Errorf("unexpected status code %v: %v", u, resp.Status)
|
||||||
|
}
|
||||||
|
|
||||||
for _, path := range paths {
|
// this is the only point at which we trust the registry. we use the
|
||||||
url := base
|
// content headers to assemble a descriptor for the name. when this becomes
|
||||||
url.Path = path
|
// more robust, we mostly get this information from a secure trust store.
|
||||||
log.G(ctx).WithField("url", url).Debug("fetch content")
|
dgstHeader := digest.Digest(resp.Header.Get("Docker-Content-Digest"))
|
||||||
|
|
||||||
req, err := http.NewRequest(http.MethodGet, url.String(), nil)
|
if dgstHeader != "" {
|
||||||
if err != nil {
|
if err := dgstHeader.Validate(); err != nil {
|
||||||
return nil, err
|
if err == nil {
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Errorf("%q in header not a valid digest", dgstHeader)
|
||||||
}
|
}
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Wrapf(err, "%q in header not a valid digest", dgstHeader)
|
||||||
req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token))
|
|
||||||
req.Header.Set("Accept", strings.Join(remotes.HintValues("mediatype", hints...), ", "))
|
|
||||||
|
|
||||||
resp, err := ctxhttp.Do(ctx, http.DefaultClient, req)
|
|
||||||
if err != nil {
|
|
||||||
return nil, err
|
|
||||||
}
|
|
||||||
|
|
||||||
if resp.StatusCode > 299 {
|
|
||||||
if resp.StatusCode == http.StatusNotFound {
|
|
||||||
continue // try one of the other urls.
|
|
||||||
}
|
|
||||||
resp.Body.Close()
|
|
||||||
return nil, errors.Errorf("unexpected status code %v: %v", url, resp.Status)
|
|
||||||
}
|
|
||||||
|
|
||||||
return resp.Body, nil
|
|
||||||
}
|
}
|
||||||
|
dgst = dgstHeader
|
||||||
|
}
|
||||||
|
|
||||||
return nil, errors.New("not found")
|
if dgst == "" {
|
||||||
}), nil
|
return "", ocispec.Descriptor{}, nil, errors.Wrapf(err, "could not resolve digest for %v", ref)
|
||||||
}), nil
|
}
|
||||||
|
|
||||||
|
var (
|
||||||
|
size int64
|
||||||
|
sizeHeader = resp.Header.Get("Content-Length")
|
||||||
|
)
|
||||||
|
|
||||||
|
size, err = strconv.ParseInt(sizeHeader, 10, 64)
|
||||||
|
if err != nil || size < 0 {
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Wrapf(err, "%q in header not a valid size", sizeHeader)
|
||||||
|
}
|
||||||
|
|
||||||
|
desc := ocispec.Descriptor{
|
||||||
|
Digest: dgst,
|
||||||
|
MediaType: resp.Header.Get("Content-Type"), // need to strip disposition?
|
||||||
|
Size: size,
|
||||||
|
}
|
||||||
|
|
||||||
|
log.G(ctx).WithField("desc.digest", desc.Digest).Debug("resolved")
|
||||||
|
return ref, desc, fetcher, nil
|
||||||
|
}
|
||||||
|
|
||||||
|
return "", ocispec.Descriptor{}, nil, errors.Errorf("%v not found", ref)
|
||||||
}
|
}
|
||||||
|
|
||||||
func getToken(ctx contextpkg.Context, scopes ...string) (string, error) {
|
func getToken(ctx contextpkg.Context, scopes ...string) (string, error) {
|
||||||
|
@ -232,39 +345,17 @@ func getToken(ctx contextpkg.Context, scopes ...string) (string, error) {
|
||||||
// getV2URLPaths generates the candidate urls paths for the object based on the
|
// getV2URLPaths generates the candidate urls paths for the object based on the
|
||||||
// set of hints and the provided object id. URLs are returned in the order of
|
// set of hints and the provided object id. URLs are returned in the order of
|
||||||
// most to least likely succeed.
|
// most to least likely succeed.
|
||||||
func getV2URLPaths(prefix, object string, hints ...string) ([]string, error) {
|
func getV2URLPaths(desc ocispec.Descriptor) ([]string, error) {
|
||||||
var urls []string
|
var urls []string
|
||||||
|
|
||||||
// TODO(stevvooe): We can probably define a higher-level "type" hint to
|
switch desc.MediaType {
|
||||||
// avoid having to do extra round trips to resolve content, as well as
|
case MediaTypeDockerSchema2Manifest, MediaTypeDockerSchema2ManifestList,
|
||||||
// avoid the tedium of providing media types.
|
ocispec.MediaTypeImageManifest, ocispec.MediaTypeImageIndex:
|
||||||
|
urls = append(urls, path.Join("manifests", desc.Digest.String()))
|
||||||
if remotes.HintExists("mediatype", MediaTypeDockerSchema2Manifest, hints...) ||
|
|
||||||
remotes.HintExists("mediatype", MediaTypeDockerSchema2ManifestList, hints...) ||
|
|
||||||
remotes.HintExists("mediatype", ocispec.MediaTypeImageManifest, hints...) ||
|
|
||||||
remotes.HintExists("mediatype", ocispec.MediaTypeImageIndex, hints...) {
|
|
||||||
// fast path out if we know we are getting a manifest. Arguably, we
|
|
||||||
// should fallback to blobs, just in case.
|
|
||||||
urls = append(urls, path.Join("/v2", prefix, "manifests", object))
|
|
||||||
}
|
}
|
||||||
|
|
||||||
// we have a digest, use blob or manifest path, depending on hints, may
|
// always fallback to attempting to get the object out of the blobs store.
|
||||||
// need to try both.
|
urls = append(urls, path.Join("blobs", desc.Digest.String()))
|
||||||
urls = append(urls, path.Join("/v2", prefix, "blobs", object))
|
|
||||||
|
|
||||||
// probably a take, so we go through the manifests endpoint
|
return urls, nil
|
||||||
urls = append(urls, path.Join("/v2", prefix, "manifests", object))
|
|
||||||
|
|
||||||
var (
|
|
||||||
noduplicates []string
|
|
||||||
seen = map[string]struct{}{}
|
|
||||||
)
|
|
||||||
for _, u := range urls {
|
|
||||||
if _, ok := seen[u]; !ok {
|
|
||||||
seen[u] = struct{}{}
|
|
||||||
noduplicates = append(noduplicates, u)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
return noduplicates, nil
|
|
||||||
}
|
}
|
||||||
|
|
139
reference/reference.go
Normal file
139
reference/reference.go
Normal file
|
@ -0,0 +1,139 @@
|
||||||
|
package reference
|
||||||
|
|
||||||
|
import (
|
||||||
|
"errors"
|
||||||
|
"fmt"
|
||||||
|
"net/url"
|
||||||
|
"path"
|
||||||
|
"regexp"
|
||||||
|
"strings"
|
||||||
|
|
||||||
|
digest "github.com/opencontainers/go-digest"
|
||||||
|
)
|
||||||
|
|
||||||
|
var (
|
||||||
|
ErrInvalid = errors.New("invalid reference")
|
||||||
|
ErrObjectRequired = errors.New("object required")
|
||||||
|
ErrHostnameRequired = errors.New("hostname required")
|
||||||
|
)
|
||||||
|
|
||||||
|
// Spec defines the main components of a reference specification.
|
||||||
|
//
|
||||||
|
// A reference specification is a schema-less URI parsed into common
|
||||||
|
// components. The two main components, locator and object, are required to be
|
||||||
|
// supported by remotes. It represents a superset of the naming define in
|
||||||
|
// docker's reference schema. It aims to be compatible but not prescriptive.
|
||||||
|
//
|
||||||
|
// While the interpretation of the components, locator and object, are up to
|
||||||
|
// the remote, we define a few common parts, accessible via helper methods.
|
||||||
|
//
|
||||||
|
// The first is the hostname, which is part of the locator. This doesn't need
|
||||||
|
// to map to a physical resource, but it must parse as a hostname. We refer to
|
||||||
|
// this as the namespace.
|
||||||
|
//
|
||||||
|
// The other component is the digest, which may be a part of the object
|
||||||
|
// identifier, always prefixed with an '@'. If present, the remote may use the
|
||||||
|
// digest portion directly or resolve it against a prefix. If the object
|
||||||
|
type Spec struct {
|
||||||
|
// Locator is the host and path portion of the specification. The host
|
||||||
|
// portion may refer to an actual host or just a namespace of related
|
||||||
|
// images.
|
||||||
|
//
|
||||||
|
// Typically, the locator may used to resolve the remote to fetch specific
|
||||||
|
// resources.
|
||||||
|
Locator string
|
||||||
|
|
||||||
|
// Object contains the identifier for the remote resource. Classically,
|
||||||
|
// this is a tag but can refer to anything in a remote. By convention, any
|
||||||
|
// portion that may be a partial or whole digest will be preceeded by an
|
||||||
|
// `@`. Anything preceeding the `@` will be referred to as the "tag".
|
||||||
|
//
|
||||||
|
// In practice, we will see this broken down into the following formats:
|
||||||
|
//
|
||||||
|
// 1. <tag>
|
||||||
|
// 2. <tag>@<digest spec>
|
||||||
|
// 3. @<digest spec>
|
||||||
|
//
|
||||||
|
// We define the tag to be anything except '@' and ':'. <digest spec> may
|
||||||
|
// be a full valid digest or shortened version, possibly with elided
|
||||||
|
// algorithm.
|
||||||
|
Object string
|
||||||
|
}
|
||||||
|
|
||||||
|
var splitRe = regexp.MustCompile(`[:@]`)
|
||||||
|
|
||||||
|
// Parse parses the string into a structured ref.
|
||||||
|
func Parse(s string) (Spec, error) {
|
||||||
|
u, err := url.Parse("dummy://" + s)
|
||||||
|
if err != nil {
|
||||||
|
return Spec{}, err
|
||||||
|
}
|
||||||
|
|
||||||
|
if u.Scheme != "dummy" {
|
||||||
|
return Spec{}, ErrInvalid
|
||||||
|
}
|
||||||
|
|
||||||
|
if u.Host == "" {
|
||||||
|
return Spec{}, ErrHostnameRequired
|
||||||
|
}
|
||||||
|
|
||||||
|
parts := splitRe.Split(u.Path, 2)
|
||||||
|
if len(parts) < 2 {
|
||||||
|
return Spec{}, ErrObjectRequired
|
||||||
|
}
|
||||||
|
|
||||||
|
// This allows us to retain the @ to signify digests or shortend digests in
|
||||||
|
// the object.
|
||||||
|
object := u.Path[len(parts[0]):]
|
||||||
|
if object[:1] == ":" {
|
||||||
|
object = object[1:]
|
||||||
|
}
|
||||||
|
|
||||||
|
return Spec{
|
||||||
|
Locator: path.Join(u.Host, parts[0]),
|
||||||
|
Object: object,
|
||||||
|
}, nil
|
||||||
|
}
|
||||||
|
|
||||||
|
// Hostname returns the hostname portion of the locator.
|
||||||
|
//
|
||||||
|
// Remotes are not required to directly access the resources at this host. This
|
||||||
|
// method is provided for convenience.
|
||||||
|
func (r Spec) Hostname() string {
|
||||||
|
i := strings.Index(r.Locator, "/")
|
||||||
|
|
||||||
|
if i < 0 {
|
||||||
|
i = len(r.Locator) + 1
|
||||||
|
}
|
||||||
|
return r.Locator[:i]
|
||||||
|
}
|
||||||
|
|
||||||
|
// Digest returns the digest portion of the reference spec. This may be a
|
||||||
|
// partial or invalid digest, which may be used to lookup a complete digest.
|
||||||
|
func (r Spec) Digest() digest.Digest {
|
||||||
|
_, dgst := SplitObject(r.Object)
|
||||||
|
return dgst
|
||||||
|
}
|
||||||
|
|
||||||
|
// String returns the normalized string for the ref.
|
||||||
|
func (r Spec) String() string {
|
||||||
|
if r.Object[:1] == "@" {
|
||||||
|
return fmt.Sprintf("%v%v", r.Locator, r.Object)
|
||||||
|
}
|
||||||
|
|
||||||
|
return fmt.Sprintf("%v:%v", r.Locator, r.Object)
|
||||||
|
}
|
||||||
|
|
||||||
|
// SplitObject provides two parts of the object spec, delimiited by an `@`
|
||||||
|
// symbol.
|
||||||
|
//
|
||||||
|
// Either may be empty and it is the callers job to validate them
|
||||||
|
// appropriately.
|
||||||
|
func SplitObject(obj string) (tag string, dgst digest.Digest) {
|
||||||
|
parts := strings.SplitAfterN(obj, "@", 2)
|
||||||
|
if len(parts) < 2 {
|
||||||
|
return parts[0], ""
|
||||||
|
} else {
|
||||||
|
return parts[0], digest.Digest(parts[1])
|
||||||
|
}
|
||||||
|
}
|
179
reference/reference_test.go
Normal file
179
reference/reference_test.go
Normal file
|
@ -0,0 +1,179 @@
|
||||||
|
package reference
|
||||||
|
|
||||||
|
import (
|
||||||
|
"testing"
|
||||||
|
|
||||||
|
digest "github.com/opencontainers/go-digest"
|
||||||
|
)
|
||||||
|
|
||||||
|
func TestReferenceParser(t *testing.T) {
|
||||||
|
for _, testcase := range []struct {
|
||||||
|
Skip bool
|
||||||
|
Name string
|
||||||
|
Input string
|
||||||
|
Normalized string
|
||||||
|
Digest digest.Digest
|
||||||
|
Hostname string
|
||||||
|
Expected Spec
|
||||||
|
Err error
|
||||||
|
}{
|
||||||
|
{
|
||||||
|
Name: "Basic",
|
||||||
|
Input: "docker.io/library/redis:foo?fooo=asdf",
|
||||||
|
Normalized: "docker.io/library/redis:foo",
|
||||||
|
Hostname: "docker.io",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "docker.io/library/redis",
|
||||||
|
Object: "foo",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "BasicWithDigest",
|
||||||
|
Input: "docker.io/library/redis:foo@sha256:abcdef?fooo=asdf",
|
||||||
|
Normalized: "docker.io/library/redis:foo@sha256:abcdef",
|
||||||
|
Hostname: "docker.io",
|
||||||
|
Digest: "sha256:abcdef",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "docker.io/library/redis",
|
||||||
|
Object: "foo@sha256:abcdef",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
|
||||||
|
{
|
||||||
|
Name: "DigestOnly",
|
||||||
|
Input: "docker.io/library/redis@sha256:abcdef?fooo=asdf",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "docker.io/library/redis",
|
||||||
|
Object: "@sha256:abcdef",
|
||||||
|
},
|
||||||
|
Hostname: "docker.io",
|
||||||
|
Normalized: "docker.io/library/redis@sha256:abcdef",
|
||||||
|
Digest: "sha256:abcdef",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "AtShortDigest",
|
||||||
|
Input: "docker.io/library/redis:obj@abcdef?fooo=asdf",
|
||||||
|
Normalized: "docker.io/library/redis:obj@abcdef",
|
||||||
|
Hostname: "docker.io",
|
||||||
|
Digest: "abcdef",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "docker.io/library/redis",
|
||||||
|
Object: "obj@abcdef",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "HostWithPort",
|
||||||
|
Input: "localhost:5000/library/redis:obj@abcdef?fooo=asdf",
|
||||||
|
Normalized: "localhost:5000/library/redis:obj@abcdef",
|
||||||
|
Hostname: "localhost:5000",
|
||||||
|
Digest: "abcdef",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "localhost:5000/library/redis",
|
||||||
|
Object: "obj@abcdef",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "HostnameRequired",
|
||||||
|
Input: "/docker.io/library/redis:obj@abcdef?fooo=asdf",
|
||||||
|
Err: ErrHostnameRequired,
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "ErrObjectRequired",
|
||||||
|
Input: "docker.io/library/redis?fooo=asdf",
|
||||||
|
Err: ErrObjectRequired,
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "Subdomain",
|
||||||
|
Input: "sub-dom1.foo.com/bar/baz/quux:latest",
|
||||||
|
Hostname: "sub-dom1.foo.com",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "sub-dom1.foo.com/bar/baz/quux",
|
||||||
|
Object: "latest",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "SubdomainWithLongTag",
|
||||||
|
Input: "sub-dom1.foo.com/bar/baz/quux:some-long-tag",
|
||||||
|
Hostname: "sub-dom1.foo.com",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "sub-dom1.foo.com/bar/baz/quux",
|
||||||
|
Object: "some-long-tag",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "AGCRAppears",
|
||||||
|
Input: "b.gcr.io/test.example.com/my-app:test.example.com",
|
||||||
|
Hostname: "b.gcr.io",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "b.gcr.io/test.example.com/my-app",
|
||||||
|
Object: "test.example.com",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Name: "Punycode",
|
||||||
|
Input: "xn--n3h.com/myimage:xn--n3h.com", // ☃.com in punycode
|
||||||
|
Hostname: "xn--n3h.com",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "xn--n3h.com/myimage",
|
||||||
|
Object: "xn--n3h.com",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
|
||||||
|
Name: "PunycodeWithDigest",
|
||||||
|
Input: "xn--7o8h.com/myimage:xn--7o8h.com@sha512:fffffff",
|
||||||
|
Hostname: "xn--7o8h.com",
|
||||||
|
Digest: "sha512:fffffff",
|
||||||
|
Expected: Spec{
|
||||||
|
Locator: "xn--7o8h.com/myimage",
|
||||||
|
Object: "xn--7o8h.com@sha512:fffffff",
|
||||||
|
},
|
||||||
|
},
|
||||||
|
{
|
||||||
|
Skip: true, // TODO(stevvooe): Implement this case.
|
||||||
|
Name: "SchemeDefined",
|
||||||
|
Input: "http://xn--7o8h.com/myimage:xn--7o8h.com@sha512:fffffff",
|
||||||
|
Hostname: "xn--7o8h.com",
|
||||||
|
Digest: "sha512:fffffff",
|
||||||
|
Err: ErrInvalid,
|
||||||
|
},
|
||||||
|
} {
|
||||||
|
t.Run(testcase.Name, func(t *testing.T) {
|
||||||
|
if testcase.Skip {
|
||||||
|
t.Skip("testcase disabled")
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
ref, err := Parse(testcase.Input)
|
||||||
|
if err != testcase.Err {
|
||||||
|
if testcase.Err != nil {
|
||||||
|
t.Fatalf("expected error %v for %q, got %v, %#v", testcase.Err, testcase.Input, err, ref)
|
||||||
|
} else {
|
||||||
|
t.Fatalf("unexpected error %v", err)
|
||||||
|
}
|
||||||
|
} else if testcase.Err != nil {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
if ref != testcase.Expected {
|
||||||
|
t.Fatalf("%#v != %#v", ref, testcase.Expected)
|
||||||
|
}
|
||||||
|
|
||||||
|
if testcase.Normalized == "" {
|
||||||
|
testcase.Normalized = testcase.Input
|
||||||
|
}
|
||||||
|
|
||||||
|
if ref.String() != testcase.Normalized {
|
||||||
|
t.Fatalf("normalization failed: %v != %v", ref.String(), testcase.Normalized)
|
||||||
|
}
|
||||||
|
|
||||||
|
if ref.Digest() != testcase.Digest {
|
||||||
|
t.Fatalf("digest extraction failed: %v != %v", ref.Digest(), testcase.Digest)
|
||||||
|
}
|
||||||
|
|
||||||
|
if ref.Hostname() != testcase.Hostname {
|
||||||
|
t.Fatalf("unexpected hostname: %v != %v", ref.Hostname(), testcase.Hostname)
|
||||||
|
}
|
||||||
|
})
|
||||||
|
}
|
||||||
|
}
|
|
@ -1,41 +0,0 @@
|
||||||
package remotes
|
|
||||||
|
|
||||||
import (
|
|
||||||
"context"
|
|
||||||
"io"
|
|
||||||
)
|
|
||||||
|
|
||||||
type Fetcher interface {
|
|
||||||
// Fetch the resource identified by id. The id is opaque to the remote, but
|
|
||||||
// may typically be a tag or a digest.
|
|
||||||
//
|
|
||||||
// Hints are provided to give instruction on how the resource may be
|
|
||||||
// fetched. They may provide information about the expected type or size.
|
|
||||||
// They may be protocol specific or help a protocol to identify the most
|
|
||||||
// efficient fetch methodology.
|
|
||||||
//
|
|
||||||
// Hints are the format of `<type>:<content>` where `<type>` is the type
|
|
||||||
// of the hint and `<content>` can be pretty much anything. For example, a
|
|
||||||
// media type hint would be the following:
|
|
||||||
//
|
|
||||||
// mediatype:application/vnd.docker.distribution.manifest.v2+json
|
|
||||||
//
|
|
||||||
// The following hint names are must be honored across all remote
|
|
||||||
// implementations:
|
|
||||||
//
|
|
||||||
// size: specify the expected size in bytes
|
|
||||||
// mediatype: specify the expected mediatype
|
|
||||||
//
|
|
||||||
// The caller should never expect the hints to be honored and should
|
|
||||||
// validate that returned content is as expected. They are only provided to
|
|
||||||
// help the remote retrieve the content.
|
|
||||||
Fetch(ctx context.Context, id string, hints ...string) (io.ReadCloser, error)
|
|
||||||
}
|
|
||||||
|
|
||||||
// FetcherFunc allows package users to implement a Fetcher with just a
|
|
||||||
// function.
|
|
||||||
type FetcherFunc func(context.Context, string, ...string) (io.ReadCloser, error)
|
|
||||||
|
|
||||||
func (fn FetcherFunc) Fetch(ctx context.Context, object string, hints ...string) (io.ReadCloser, error) {
|
|
||||||
return fn(ctx, object, hints...)
|
|
||||||
}
|
|
|
@ -1,19 +1,37 @@
|
||||||
package remotes
|
package remotes
|
||||||
|
|
||||||
import "context"
|
import (
|
||||||
|
"context"
|
||||||
|
"io"
|
||||||
|
|
||||||
|
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
|
||||||
|
)
|
||||||
|
|
||||||
// Resolver provides a remote based on a locator.
|
// Resolver provides a remote based on a locator.
|
||||||
type Resolver interface {
|
type Resolver interface {
|
||||||
// Resolve returns a remote from the locator.
|
// Resolve attempts to resolve the reference into a name and descriptor.
|
||||||
//
|
//
|
||||||
// A locator is a scheme-less URI representing the remote. Structurally, it
|
// The argument `ref` should be a scheme-less URI representing the remote.
|
||||||
// has a host and path. The "host" can be used to directly reference a
|
// Structurally, it has a host and path. The "host" can be used to directly
|
||||||
// specific host or be matched against a specific handler.
|
// reference a specific host or be matched against a specific handler.
|
||||||
Resolve(ctx context.Context, locator string) (Fetcher, error)
|
//
|
||||||
|
// The returned name should be used to identify the referenced entity.
|
||||||
|
// Dependending on the remote namespace, this may be immutable or mutable.
|
||||||
|
// While the name may differ from ref, it should itself be a valid ref.
|
||||||
|
//
|
||||||
|
// If the resolution fails, an error will be returned.
|
||||||
|
Resolve(ctx context.Context, ref string) (name string, desc ocispec.Descriptor, fetcher Fetcher, err error)
|
||||||
}
|
}
|
||||||
|
|
||||||
type ResolverFunc func(context.Context, string) (Fetcher, error)
|
type Fetcher interface {
|
||||||
|
// Fetch the resource identified by the descriptor.
|
||||||
func (fn ResolverFunc) Resolve(ctx context.Context, locator string) (Fetcher, error) {
|
Fetch(ctx context.Context, desc ocispec.Descriptor) (io.ReadCloser, error)
|
||||||
return fn(ctx, locator)
|
}
|
||||||
|
|
||||||
|
// FetcherFunc allows package users to implement a Fetcher with just a
|
||||||
|
// function.
|
||||||
|
type FetcherFunc func(ctx context.Context, desc ocispec.Descriptor) (io.ReadCloser, error)
|
||||||
|
|
||||||
|
func (fn FetcherFunc) Fetch(ctx context.Context, desc ocispec.Descriptor) (io.ReadCloser, error) {
|
||||||
|
return fn(ctx, desc)
|
||||||
}
|
}
|
||||||
|
|
Loading…
Reference in a new issue