diff --git a/client.go b/client.go index bc86590c2..5b34799f3 100644 --- a/client.go +++ b/client.go @@ -403,12 +403,22 @@ func (c *Client) fetch(ctx context.Context, rCtx *RemoteContext, ref string, lim } var ( - schema1Converter *schema1.Converter - handler images.Handler + handler images.Handler + + isConvertible bool + converterFunc func(context.Context, ocispec.Descriptor) (ocispec.Descriptor, error) ) + if desc.MediaType == images.MediaTypeDockerSchema1Manifest && rCtx.ConvertSchema1 { - schema1Converter = schema1.NewConverter(store, fetcher) + schema1Converter := schema1.NewConverter(store, fetcher) + handler = images.Handlers(append(rCtx.BaseHandlers, schema1Converter)...) + + isConvertible = true + + converterFunc = func(ctx context.Context, _ ocispec.Descriptor) (ocispec.Descriptor, error) { + return schema1Converter.Convert(ctx) + } } else { // Get all the children for a descriptor childrenHandler := images.ChildrenHandler(store) @@ -421,18 +431,34 @@ func (c *Client) fetch(ctx context.Context, rCtx *RemoteContext, ref string, lim childrenHandler = images.LimitManifests(childrenHandler, rCtx.PlatformMatcher, limit) } + // set isConvertible to true if there is application/octet-stream media type + convertibleHandler := images.HandlerFunc( + func(_ context.Context, desc ocispec.Descriptor) ([]ocispec.Descriptor, error) { + if desc.MediaType == docker.LegacyConfigMediaType { + isConvertible = true + } + + return []ocispec.Descriptor{}, nil + }, + ) + handler = images.Handlers(append(rCtx.BaseHandlers, remotes.FetchHandler(store, fetcher), + convertibleHandler, childrenHandler, )...) + + converterFunc = func(ctx context.Context, desc ocispec.Descriptor) (ocispec.Descriptor, error) { + return docker.ConvertManifest(ctx, store, desc) + } } if err := images.Dispatch(ctx, handler, desc); err != nil { return images.Image{}, err } - if schema1Converter != nil { - desc, err = schema1Converter.Convert(ctx) - if err != nil { + + if isConvertible { + if desc, err = converterFunc(ctx, desc); err != nil { return images.Image{}, err } } diff --git a/remotes/docker/converter.go b/remotes/docker/converter.go new file mode 100644 index 000000000..43e6b372c --- /dev/null +++ b/remotes/docker/converter.go @@ -0,0 +1,88 @@ +/* + Copyright The containerd Authors. + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +*/ + +package docker + +import ( + "bytes" + "context" + "encoding/json" + "fmt" + + "github.com/containerd/containerd/content" + "github.com/containerd/containerd/images" + "github.com/containerd/containerd/log" + "github.com/containerd/containerd/remotes" + digest "github.com/opencontainers/go-digest" + ocispec "github.com/opencontainers/image-spec/specs-go/v1" + "github.com/pkg/errors" +) + +// LegacyConfigMediaType should be replaced by OCI image spec. +// +// More detail: docker/distribution#1622 +const LegacyConfigMediaType = "application/octet-stream" + +// ConvertManifest changes application/octet-stream to schema2 config media type if need. +// +// NOTE: +// 1. original manifest will be deleted by next gc round. +// 2. don't cover manifest list. +func ConvertManifest(ctx context.Context, store content.Store, desc ocispec.Descriptor) (ocispec.Descriptor, error) { + if !(desc.MediaType == images.MediaTypeDockerSchema2Manifest || + desc.MediaType == ocispec.MediaTypeImageManifest) { + + log.G(ctx).Warnf("do nothing for media type: %s", desc.MediaType) + return desc, nil + } + + // read manifest data + mb, err := content.ReadBlob(ctx, store, desc) + if err != nil { + return ocispec.Descriptor{}, errors.Wrap(err, "failed to read index data") + } + + var manifest ocispec.Manifest + if err := json.Unmarshal(mb, &manifest); err != nil { + return ocispec.Descriptor{}, errors.Wrap(err, "failed to unmarshal data into manifest") + } + + // check config media type + if manifest.Config.MediaType != LegacyConfigMediaType { + return desc, nil + } + + manifest.Config.MediaType = images.MediaTypeDockerSchema2Config + data, err := json.MarshalIndent(manifest, "", " ") + if err != nil { + return ocispec.Descriptor{}, errors.Wrap(err, "failed to marshal manifest") + } + + // update manifest with gc labels + desc.Digest = digest.Canonical.FromBytes(data) + desc.Size = int64(len(data)) + + labels := map[string]string{} + for i, c := range append([]ocispec.Descriptor{manifest.Config}, manifest.Layers...) { + labels[fmt.Sprintf("containerd.io/gc.ref.content.%d", i)] = c.Digest.String() + } + + ref := remotes.MakeRefKey(ctx, desc) + if err := content.WriteBlob(ctx, store, ref, bytes.NewReader(data), desc, content.WithLabels(labels)); err != nil { + return ocispec.Descriptor{}, errors.Wrap(err, "failed to update content") + } + return desc, nil +}