containerd/remotes/resolver.go

38 lines
1.3 KiB
Go

package remotes
import (
"context"
"io"
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
)
// Resolver provides a remote based on a locator.
type Resolver interface {
// Resolve attempts to resolve the reference into a name and descriptor.
//
// The argument `ref` should be a scheme-less URI representing the remote.
// Structurally, it has a host and path. The "host" can be used to directly
// reference a specific host or be matched against a specific handler.
//
// 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 Fetcher interface {
// Fetch the resource identified by the descriptor.
Fetch(ctx context.Context, desc ocispec.Descriptor) (io.ReadCloser, error)
}
// 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)
}