/**
     * 支付宝 退款
   * @user 一秋
    * @param $out_trade_no
     * @param $refund_amount
     * @return bool
     * @throws Exception
     */
    public static function AliPayPlaceRefund($out_trade_no,$refund_amount){
        $refund_order = generateOrderId(9);
        $aop = new \AopClient ();
        $aop->gatewayUrl =  config(‘alipay.gatewayUrl‘);
        $aop->appId = config(‘alipay.appId‘);
        $aop->rsaPrivateKey = config(‘alipay.rsaPrivateKey‘);
        $aop->alipayrsaPublicKey = config(‘alipay.alipayrsaPublicKey‘);
        $aop->apiVersion = ‘1.0‘;
        $aop->signType = ‘RSA2‘;
        $aop->postCharset=‘utf-8‘;
        $aop->format=‘json‘;
        $request = new \AlipayTradeRefundRequest();
        $request->setBizContent("{" .
//            "\"trade_no\":\"2017112821001004030523090753\"," .
            "\"out_trade_no\":\"$out_trade_no\"," .
            "\"refund_amount\":$refund_amount," .
            "\"refund_reason\":\"正常退款\"," .
            "\"out_request_no\":\"$refund_order\"," .
            "\"operator_id\":\"OP001\"," .
            "\"store_id\":\"NJ_S_001\"," .
            "\"terminal_id\":\"NJ_T_001\"" .
            "  }");

        $result = $aop->execute ( $request );
        $responseNode = str_replace(".", "_", $request->getApiMethodName()) . "_response";
        $resultCode = $result->$responseNode->code;

        if(!empty($resultCode)&&$resultCode == 10000){
//            echo "成功";
            return true;
        } else {
//            echo "失败";
            throw new Exception($result->$responseNode->sub_msg);
        }
    }