buildkit/util/contentutil/refs.go

99 lines
2.1 KiB
Go

package contentutil
import (
"context"
"net/http"
"sync"
"github.com/containerd/containerd/content"
"github.com/containerd/containerd/errdefs"
"github.com/containerd/containerd/remotes"
"github.com/containerd/containerd/remotes/docker"
"github.com/moby/locker"
digest "github.com/opencontainers/go-digest"
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/pkg/errors"
)
func ProviderFromRef(ref string) (ocispec.Descriptor, content.Provider, error) {
remote := docker.NewResolver(docker.ResolverOptions{
Client: http.DefaultClient,
})
name, desc, err := remote.Resolve(context.TODO(), ref)
if err != nil {
return ocispec.Descriptor{}, nil, err
}
fetcher, err := remote.Fetcher(context.TODO(), name)
if err != nil {
return ocispec.Descriptor{}, nil, err
}
return desc, FromFetcher(fetcher), nil
}
func IngesterFromRef(ref string) (content.Ingester, error) {
remote := docker.NewResolver(docker.ResolverOptions{
Client: http.DefaultClient,
})
pusher, err := remote.Pusher(context.TODO(), ref)
if err != nil {
return nil, err
}
return &ingester{
locker: locker.New(),
pusher: pusher,
}, nil
}
type ingester struct {
locker *locker.Locker
pusher remotes.Pusher
}
func (w *ingester) Writer(ctx context.Context, opts ...content.WriterOpt) (content.Writer, error) {
var wo content.WriterOpts
for _, o := range opts {
if err := o(&wo); err != nil {
return nil, err
}
}
if wo.Ref == "" {
return nil, errors.Wrap(errdefs.ErrInvalidArgument, "ref must not be empty")
}
w.locker.Lock(wo.Ref)
var once sync.Once
unlock := func() {
once.Do(func() {
w.locker.Unlock(wo.Ref)
})
}
writer, err := w.pusher.Push(ctx, wo.Desc)
if err != nil {
unlock()
return nil, err
}
return &lockedWriter{unlock: unlock, Writer: writer}, nil
}
type lockedWriter struct {
unlock func()
content.Writer
}
func (w *lockedWriter) Commit(ctx context.Context, size int64, expected digest.Digest, opts ...content.Opt) error {
err := w.Writer.Commit(ctx, size, expected, opts...)
if err == nil {
w.unlock()
}
return err
}
func (w *lockedWriter) Close() error {
err := w.Writer.Close()
w.unlock()
return err
}