func verboseName(name reference.Named) string {
name = reference.WithDefaultTag(name)
tag := ""
if tagged, ok := name.(reference.NamedTagged); ok {
tag = tagged.Tag()
}
return name.FullName() + ":" + tag
}
// DockerReferenceIdentity returns a string representation of the reference, suitable for policy lookup,
// as a backend for ImageReference.PolicyConfigurationIdentity.
// The reference must satisfy !reference.IsNameOnly().
func DockerReferenceIdentity(ref reference.Named) (string, error) {
res := ref.FullName()
tagged, isTagged := ref.(reference.NamedTagged)
digested, isDigested := ref.(reference.Canonical)
switch {
case isTagged && isDigested: // This should not happen, docker/reference.ParseNamed drops the tag.
return "", errors.Errorf("Unexpected Docker reference %s with both a name and a digest", ref.String())
case !isTagged && !isDigested: // This should not happen, the caller is expected to ensure !reference.IsNameOnly()
return "", errors.Errorf("Internal inconsistency: Docker reference %s with neither a tag nor a digest", ref.String())
case isTagged:
res = res + ":" + tagged.Tag()
case isDigested:
res = res + "@" + digested.Digest().String()
default: // Coverage: The above was supposed to be exhaustive.
return "", errors.New("Internal inconsistency, unexpected default branch")
}
return res, nil
}
// DockerReferenceNamespaces returns a list of other policy configuration namespaces to search,
// as a backend for ImageReference.PolicyConfigurationIdentity.
// The reference must satisfy !reference.IsNameOnly().
func DockerReferenceNamespaces(ref reference.Named) []string {
// Look for a match of the repository, and then of the possible parent
// namespaces. Note that this only happens on the expanded host names
// and repository names, i.e. "busybox" is looked up as "docker.io/library/busybox",
// then in its parent "docker.io/library"; in none of "busybox",
// un-namespaced "library" nor in "" supposedly implicitly representing "library/".
//
// ref.FullName() == ref.Hostname() + "/" + ref.RemoteName(), so the last
// iteration matches the host name (for any namespace).
res := []string{}
name := ref.FullName()
for {
res = append(res, name)
lastSlash := strings.LastIndex(name, "/")
if lastSlash == -1 {
break
}
name = name[:lastSlash]
}
return res
}