as_header(); * * [!!] This method implements [OAuth 2.0 v22 Spec 7.1](http://tools.ietf.org/html/draft-ietf-oauth-v2-22#section-7.1). * * @return string */ public function as_header() { if ($access = Arr::get($this->params, 'access_token')) { if (is_string($this->send_header)) { $header = $this->send_header; } else { $header = 'Bearer'; } $access = $header.' '.$access; } return $access ? $access : NULL; } }