public function getRequestToken()
    {
        // Nullify any request token we already have
        $this->storage->set(null, 'request_token');
        $url = API::API_URL . self::REQUEST_TOKEN_METHOD;
        $response = $this->fetch('POST', $url, '');
        $token = $this->parseTokenString($response['body']);
        $this->storage->set($token, 'request_token');
    }