buildkit/source/identifier.go

57 lines
1.1 KiB
Go

package source
import (
"strings"
"github.com/containerd/containerd/reference"
"github.com/pkg/errors"
)
var (
errInvalid = errors.New("invalid")
errNotFound = errors.New("not found")
)
const (
DockerImageScheme = "docker-image"
)
type Identifier interface {
ID() string // until sources are in process this string comparison could be avoided
}
func FromString(s string) (Identifier, error) {
// TODO: improve this
parts := strings.SplitN(s, "://", 2)
if len(parts) != 2 {
return nil, errors.Wrapf(errInvalid, "failed to parse %s", s)
}
switch parts[0] {
case DockerImageScheme:
return NewImageIdentifier(parts[1])
default:
return nil, errors.Wrapf(errNotFound, "unknown schema %s", parts[0])
}
}
type ImageIdentifier struct {
Reference reference.Spec
}
func NewImageIdentifier(str string) (*ImageIdentifier, error) {
ref, err := reference.Parse(str)
if err != nil {
return nil, errors.WithStack(err)
}
if ref.Object == "" {
return nil, errors.WithStack(reference.ErrObjectRequired)
}
return &ImageIdentifier{Reference: ref}, nil
}
func (i *ImageIdentifier) ID() string {
return DockerImageScheme
}