cmd/dist: default mediatypes to oci and docker
To make using the `fetch-object` for demonstrations much easier, the
mediatypes are defaulted when a non-digest object identifier is
provided. We also add support for OCI mediatypes, although they are
mostly unavailable.
@@ -16,11 +16,17 @@ import (
"github.com/docker/containerd/log"
"github.com/docker/containerd/remotes"
digest "github.com/opencontainers/go-digest"
+ ocispec "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/pkg/errors"
"github.com/urfave/cli"
"golang.org/x/net/context/ctxhttp"
)
+const (
+ MediaTypeDockerSchema2Manifest = "application/vnd.docker.distribution.manifest.v2+json"
+ MediaTypeDockerSchema2ManifestList = "application/vnd.docker.distribution.manifest.list.v2+json"
+)
+
// TODO(stevvooe): Create "multi-fetch" mode that just takes a remote
// then receives object/hint lines on stdin, returning content as
// needed.
@@ -133,6 +139,14 @@ func getResolver(ctx contextpkg.Context) (remotes.Resolver, error) {
},
))
+ if _, err := digest.Parse(object); err != nil {
+ // in this case, we are seeking a manifest by a tag. Let's add some hints.
+ hints = append(hints, "mediatype:"+MediaTypeDockerSchema2Manifest)
+ hints = append(hints, "mediatype:"+MediaTypeDockerSchema2ManifestList)
+ hints = append(hints, "mediatype:"+ocispec.MediaTypeImageManifest)
+ hints = append(hints, "mediatype:"+ocispec.MediaTypeImageIndex)
+ }
+
paths, err := getV2URLPaths(prefix, object, hints...)
if err != nil {
return nil, err
@@ -149,9 +163,7 @@ func getResolver(ctx contextpkg.Context) (remotes.Resolver, error) {
}
req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token))
- for _, mediatype := range remotes.HintValues("mediatype", hints...) {
- req.Header.Set("Accept", mediatype)
- }
+ req.Header.Set("Accept", strings.Join(remotes.HintValues("mediatype", hints...), ", "))
resp, err := ctxhttp.Do(ctx, http.DefaultClient, req)
if err != nil {
@@ -227,18 +239,18 @@ func getV2URLPaths(prefix, object string, hints ...string) ([]string, error) {
// avoid having to do extra round trips to resolve content, as well as
// avoid the tedium of providing media types.
- if remotes.HintExists("mediatype", "application/vnd.docker.distribution.manifest.v2+json", hints...) { // TODO(stevvooe): make this handle oci types, as well.
+ 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))
}
- _, err := digest.Parse(object)
- if err == nil {
// we have a digest, use blob or manifest path, depending on hints, may
// need to try both.
urls = append(urls, path.Join("/v2", prefix, "blobs", object))
- }
// probably a take, so we go through the manifests endpoint
urls = append(urls, path.Join("/v2", prefix, "manifests", object))
