// openURI returns a ReadCloser for the given URI. Supports http://, https://, and file:// schemes.
func (a *defaultTokenKeyProvider) openURI(uri string) (io.ReadCloser, error) {
default_token_key_provider.go
u, err := url.Parse(uri)
if err != nil {
return nil, err
}
if u.Host != "" && u.Host != "localhost" {
return nil, fmt.Errorf("file URI with remote host is not supported: %s", uri)
}