func imageIDFromList(d dockerclient.Client, imageName string) (string, error) {
images, err := d.ListImages()
if err != nil {
return "", stackerr.Wrap(err)
}
for _, i := range images {
for _, t := range i.RepoTags {
if t == imageName {
return i.Id, nil
}
}
}
return "", nil
}